Patent Application
20230404377
The present disclosure relates to an endoscope comprising a proximal endoscope handle, a distal tip unit configured to be inserted into a patient's body cavity, an endoscope shaft connecting the endoscope handle and the distal tip unit, a working channel provided in the endoscope shaft and extending from the endoscope handle towards the distal tip unit and a suction valve configured to control a suction through the working channel and having a valve closed state and a valve open state. The suction valve comprises: a housing having an inlet opening connected to the working channel and an outlet opening; and a piston unit inserted in the housing. The piston unit comprises a movable piston, a button attached to the piston, a fixation ring arranged stationary in the housing and a spring arranged and acting between the fixation ring and the button or piston.
Endoscopes and similar specialized instruments such as bronchoscopes, arthroscopes, colonoscopes, laparoscopes 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. Basically, a distal tip unit of an endoscope, which is connected to an endoscope handle via an endoscope shaft, can be inserted into a hollow organ or body cavity to be investigated with the endoscope. Both reusable and disposable endoscopes are known from the state of the art.
When examining an object such as a body cavity or hollow organ with an endoscope it is desirable to have a clear view/visibility of the examined object. However, the visibility of such an object is often affected by mucus or other undesirable fluid content. It is thus desirable to remove such mucus or undesirable fluid content using a suction device, such as a vacuum pump. In order to connect the suction device to the endoscope and to control a suction that shall be applied to the examined object, it is basically known to use/provide a suction valve.
For example, a suction valve for an endoscope may be connected to a working channel of the endoscope and may be configured to allow or prevent a suction/suction effect in the working channel. When the suction valve is in a valve closed position (i.e. a closed position of the suction valve), a fluid/air flow through the working channel is blocked by the suction valve. When suction is desired in the working channel, an operator/a user can (manually) operate the suction valve (e.g. by depressing a button of the valve) in order to bring the suction valve in a valve open position (i.e. an open position of the suction valve). In the open position of the suction valve a flow channel inside the suction valve connects the working channel to the suction device. In particular, the suction device creates a negative (suction) pressure that draws fluid/air out of the working channel and out of an outlet opening provided in the suction valve. When the operator releases the suction valve (e.g. by not depressing the button anymore), the valve returns to its valve closed position that prohibits fluid/air flow and ends the suctioning out of the working channel. Often, the suction valve is removable from the endoscope/an endoscope handle so that potential blockage of the valve can be removed.
Basically, suction valves comprising a housing and a piston that is movable within the housing are well-known.
For example, U.S. Pat. No. 5,871,441 A discloses a suction valve that can be connected to a working channel of an endoscope and includes a (cylindrical) housing, a piston, a spring and a button. The piston is provided with a flow channel and is movably accommodated within the housing. The button (on top of the piston) is connected to the piston such that the piston is movable together with the button. An operator can press the button to move the piston from a valve closed state to a valve open state. The spring ensures that the valve is usually in the valve closed state, in particular when the operator does not press down the button. The housing is provided with an inlet opening that is connected to the working channel of the endoscope and with an outlet opening that is connected to a suction device. Usually, the suction device is active/running. When the valve is in the valve closed state an outer circumferential surface of the cylindrically shaped piston blocks the inlet opening. When the operator presses down the button, the piston is moved downwards such that the flow channel of the piston connects the inlet opening of the housing with the outlet opening of the housing, and a fluid flow through the suction valve is enabled. Hence, fluid/air can be drawn from the working channel of the endoscope through the suction valve.
DE 196 10 312 A1 discloses a suction valve that is assembled in a similar way as the suction valve disclosed in U.S. Pat. No. 5,871,441 A.
Usually, for reusable endoscopes suction valves are used that generally comprise metal parts. Metal parts can be manufactured with high precision and the valves can include proper sealings that ensure a good performance of the suction valves. However, for single use endoscopes/disposable endoscopes this solution is too expensive and resource-demanding. For single use endoscopes it is thus preferable to provide a suction valve which is essentially produced/manufactured of plastic/polymer/synthetic material. Plastic parts however cannot be produced as accurately as metal parts. In particular, for plastic parts tolerances are bigger than for metal parts. Furthermore, surfaces of molded plastic parts are usually slightly tapered (in order to allow removal of a mold/a mold core) which leads to challenges ensuring a proper sealing of the valve.
In particular, suction valves essentially made of plastic parts have the drawback that residual suction from the working channel (entering the suction valve over the inlet opening) occurs in the valve closed state. Therefore, it is necessary to improve a sealing of the inlet opening in the valve closed state. As for disposable endoscopes/suction valves for disposable endoscopes usually (molded) plastic parts are used, the sealing between two surfaces cannot be easily achieved by a flat contact of these surfaces. Hence, additional sealing (means) should be provided to reduce/eliminate the residual flow.
Against this background, EP 2 645 921 B1 discloses a disposable suction valve for an endoscope with a stem (piston) providing an air passage through a center bore. Furthermore, the suction valve includes a spring stanchion cup and a spring as well as a boot that is placed over the exterior of the spring stanchion cup. The spring stanchion cup comprises an opening to receive the stem and to allow movement of the stem between an upward and a downward position. The spring is placed between the spring stanchion cup and the stem. A separate/additional sealing ledge is provided at the spring stanchion cup to seal off a suction port in the endoscope.
A major drawback of the existing solutions is that an additional and/or separate seal is necessary to reduce/eliminate the residual suction.
The tasks and objectives of the present disclosure are to eliminate or at least to reduce the disadvantages of the prior art. In particular, a suction valve shall be provided that at least reduces, preferably eliminates, the residual suction through the suction valve without additional and/or separate seals. When providing a suction valve with less individual parts, the assembly of such suction valve can be eased and the costs of such suction valve can be reduced.
The tasks and objectives are solved by an endoscope in accordance with claim 1 and by a system in accordance with claim 13. Advantageous embodiments are claimed in the dependent claims and/or are explained below.
The present disclosure relates to an endoscope, preferably a single use endoscope, that comprises a proximal endoscope handle, a distal tip unit configured to be inserted into a patient's body cavity, an endoscope shaft connecting the endoscope handle and the distal tip unit, a working channel provided in the endoscope shaft and extending from the endoscope handle towards the distal tip unit and a suction valve configured to control a suction through the working channel and having a valve closed state and a valve open state. The suction valve comprises: a housing having an inlet opening connected to the working channel and an outlet opening; and a piston unit inserted in the housing. The piston unit comprises a movable piston, a button attached to the piston, a fixation ring arranged stationary/immovable in the housing and a spring arranged and acting between the fixation ring and the button or piston. The fixation ring is configured to urge the piston towards the inlet opening of the housing in the valve closed state.
In other words, the present disclosure provides a suction valve having, inter alia, a fixation ring and a piston, the fixation ring and the piston working together to seal/close the inlet opening of the housing in a valve closed state. In particular, in the valve closed state a peripheral/circumferential portion of the piston is urged/pressed towards/against the inlet opening of the housing by the fixation ring.
Advantageously, the set-up/the assembly of the suction valve according to the disclosure uses the piston and fixation ring which are configured in a way that they can interact in order to provide a better sealing against undesired residual suction entering the suction valve via the inlet opening in the valve closed state. This renders any further separate and/or additional seals for sealing the inlet opening against residual suction in the valve closed state unnecessary. As according to the present disclosure no further additional and/or separate seals are necessary for the suction valve, the assembly of the suction valve is simplified and the production costs of the suction valve are reduced.
The suction valve, in particular the parts thereof, may be made of a plastic material/polymer. Especially preferred, the suction valve, in particular parts thereof, preferably the housing, the piston, the button and the fixation ring, may be manufactured in an injection molding process/may be injection molded parts.
Preferably, the housing and/or the piston and/or the fixation ring and/or the button are made from a thermoplastic polymer, e.g. polystyrene (PS), polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polyoxymethylene (POM), etc. However, also other polymer materials/other materials are conceivable. In particular, it may be preferred if the fixation ring is made from a metal, e.g. stainless steel.
Especially preferred, at least two different (polymer) materials are used for the housing, the piston and the fixation ring. Using two or three different material, in particular polymer materials, for the housing, the piston and the fixation ring helps to reduce friction between these parts.
The housing of the suction valve may be formed essentially cylindrically. In this way, the housing is easy to handle and to manufacture.
Preferably, the spring is configured to urge the suction valve into the valve closed state when no external force, e.g. a pressing force by a user, acts on the button. Hence, when no external force acts on the button, the suction valve is preferably in the valve closed state. In a preferred way, the suction valve is configured such that it is brought into the valve open state when the button is pressed by a user (i.e. when an external pressing force acts on the button). For this purpose, the piston may be movable together with the button.
Moreover, the piston may be configured to seal the inlet opening in the valve closed state, and the piston may be configured to enable a fluid flow between the inlet opening and the outlet opening of the housing in the valve open state.
In a preferred embodiment, the outlet opening of the housing is configured to be connected/to be connectable to a suction device, in particular a vacuum pump. Usually such suction devices are running continuously, no matter if the valve is closed or open. In this way, the suction device may permanently exert suction to the suction valve.
Against this background, the suction valve may be configured such that suction from the working channel is performed (only) in the valve open state. In the valve closed state, a negligibly small, preferably no (residual) suction from the working channel may be suctioned through the suction valve.
Moreover, the suction valve may be configured to manually control the suction through the working channel, in particular by pressing the button towards the housing by a user. In this way, a user can easily control the suction valve and can switch between the valve closed state and the valve open state.
Furthermore, it may be preferred when the suction valve is configured to be removably attachable to the endoscope, in particular to the endoscope handle. In this way, when the suction valve can easily be removed from the endoscope/the endoscope handle, the suction valve can be easily cleaned.
In a further preferred embodiment of the suction valve, the inlet opening is connected to the working channel of the endoscope via a suction tube. In this way, an optimal coupling between the suction valve and the working channel of the endoscope can be ensured.
Moreover, the suction tube ensures to minimize suction losses between (the inlet opening of) the suction valve and the working channel of the endoscope. There may also be a biopsy connector having a biopsy valve be arranged between the suction tube and the working channel. Anyway, it is preferred if there is not a direct connection between the inlet opening and the working channel.
The button may comprise a round button cover portion and a cylindrical button shell portion extending from the button cover portion. This constitutes an easy-to-manufacture design of the button.
Preferably, the button is configured to snap to the housing, in particular to make a snap connection with the housing. In this way, it is very easy to connect the button to the housing.
Moreover, the button may be configured to limit a movement of the piston when the spring urges the button or the piston into the valve closed state. In this way, the button does not part from the housing unintentionally.
Preferentially, the button may be provided with at least one slit, preferably several slits, that allow(s) a leakage flow in the valve closed state. A leakage flow is the drawing in of surrounding air through slit(s) in the button. By providing the button with such slit(s), surrounding air is suctioned through the suction valve and hence the residual suction entering the suction valve over the inlet opening can be reduced or even eliminated. Leakage flow further reduces or even eliminates the risk of excessive initial suction when opening the valve.
The leakage slit(s) may be provided in the button shell portion. Furthermore, the leakage slit(s) may have an elongated slotted shape. Preferably, a plurality of circumferentially (equidistantly) spaced apart leakage slit(s) are provided in the button shell portion. With such a design, the button is configured to provide an appropriate leakage flow through the suction valve in the valve closed state to reduce or even eliminate the residual suction through the inlet opening.
The button may further be provided with an inwardly protruding portion protruding inwardly from the button cover portion wherein the inwardly protruding portion may be configured to snap onto the piston. Against this background, the piston may be provided with a holding arrangement configured to be complementary with the inwardly protruding portion of the button. In this way, the piston can easily be fixed to the button (in a snap-fit manner), in order to be movable with the button.
Furthermore, the fixation ring may be configured to assist in sealing the piston in the valve closed state (when the valve is closed). When the fixation ring urges the piston against the inlet opening, the piston seals the inlet opening against (residual) suction in the valve closed state. This is an easy way to seal the inlet opening without having to provide an additional and/or separate sealing.
In a preferred embodiment, the fixation ring has a ring-shaped/annular/circular portion and a protruding portion, extending along the piston/extending axially away from the ring-shaped portion. Preferably, at least an end portion of the protruding portion is brought into contact with the piston at least in the valve closed state to urge the piston towards/against the inlet opening of the housing.
Preferably, the protruding portion, in particular at least an end portion thereof, is arranged diametrically opposed with respect to the inlet opening of the housing. This results in that the urging effect of the fixation ring onto the piston against the inlet opening is optimal.
Additionally, the piston may have a first (side) opening, a second (bottom) opening and a flow channel enabling fluid flow between the first opening and the second opening.
In the valve open state the first (side) opening, the second (bottom) opening and the flow channel of the piston may connect the inlet opening of the housing with the outlet opening of the housing. Hence, when the piston is arranged appropriately within the housing in the valve open state, the piston allows a fluid flow between the inlet opening and the outlet opening. For this purpose, in the valve open state, the first opening of the piston should be in flush contact with the inlet opening of the housing.
Moreover, the piston may comprise a first (upper) piston portion, a second (lower) piston portion and a transition area between the first piston portion and the second piston portion.
The first piston portion may be a portion of the piston that is fixed to the button (at a free end of the first piston portion), wherein the second piston portion may be a portion of the piston having the first opening, the second opening and the flow channel.
The piston may have an essentially cylindrical shape and the fixation ring, in particular the ring-shaped/annular/circular portion thereof, may encircle/enclose/surround the piston, in particular the first (upper) piston portion. In this way, the fixation ring can easily be coupled with the piston while the piston is movable relative to the fixation ring.
The fixation ring may be fixed to the housing, e.g. frictionally connected or positively connected (form-fit), when the piston unit is installed in the housing.
Furthermore, the piston may have a radially outwardly protruding rim portion in the transition area between the first piston portion and the second piston portion, wherein the radially outwardly protruding rim portion may be urged against the fixation ring by the spring in the valve closed state. Thus, this radially outwardly protruding rim portion functions as an abutment of the piston against the fixation ring in the valve closed state.
In a preferred embodiment, the protruding portion extends from the annular/cylindrical/ring-shaped portion towards and along the second piston portion in an axial direction of the piston.
Preferably, the second piston portion has an axially extending (essentially cylindrical) shell portion which may be interrupted by/provided with a planar surface that extends in a length direction of the piston. This planar surface may be configured to contact the inlet opening of the housing. The planar surface may provide the first opening configured to be flush with the inlet opening of the housing in the valve open state. When the piston is provided with a planar surface at the position where the piston contacts the inlet opening of the housing and when the inner surface of the housing is provided with a correspondingly flat surface at a position around/next to the inlet opening, in the valve closed state these planar surfaces very effectively improve the sealing between the piston and the inlet opening. In the valve open, state this planar surface very effectively allows a flushing coupling between the first opening and the inlet opening such that suction losses can be minimized.
The urging effect of the fixation ring that urges/presses the piston towards the inlet opening of the housing can be embodied in at least two ways. The first and second embodiment described hereinafter can either be used independently from each other or can be combined with one another.
A first embodiment that achieves the urging effect, relates thereto that the protruding portion is designed as a spring-type finger, urging the piston towards the inlet opening by a spring force. In this way, a common piston can be used because simply the spring force of the protruding portion urges the piston against the inlet opening in order to provide the sealing effect. Preferably, the spring-type finger is configured as a leaf spring. Such leaf springs are cheap and easy to handle.
Basically, it may be preferred if the fixation ring is made of an inexpensive polymer material in the first embodiment. In order to increase a shelf life of the spring-type finger it may however be also preferred if the fixation ring is made of a metal, in particular stainless steel, in the first embodiment.
A second embodiment that achieves the urging effect, may be directed thereto that the second piston portion has, besides the axially extending (essentially cylindrical) shell portion, an inclined portion integrally connected/formed at an end of the axially extending (cylindrical) shell portion, wherein in the inclined portion an outer diameter/radius/extension of the piston gradually/continuously/linearly increases from the axially extending shell portion, and wherein the protruding portion of the fixation ring is formed like a wedge and engages at least with the inclined portion in the valve closed state, thus urging the inclined portion towards/in direction of the inlet opening of the housing. In this embodiment, the protruding portion of the fixation ring that is formed like a wedge contacts the inclined portion and hence presses the piston against the inlet opening. Thereby the piston seals the inlet opening against undesired (residual) suction.
Moreover, an obtuse angle (an angle between 90° and 180°) may be formed between the axially extending shell portion and the inclined portion.
Additionally, in the second embodiment, the second piston portion may have a radially outwardly protruding flange portion at an (free) end of the second piston portion while the inclined portion is arranged between the axially extending shell portion and the radially outwardly protruding flange portion, wherein in the inclined portion an outer diameter/radius/ extension of the piston gradually/continuously/linearly increases from the axially extending shell portion to the radially outwardly protruding flange portion. The herewith provided flange portion ensures a strong and safe engagement of the wedge-like protruding portion with the inclined portion.
This second embodiment achieves that the urging effect is very robust and insensitive to long storage.
Furthermore, the present disclosure relates to a system comprising the endoscope described before wherein the system further comprises a suction device that is connectable to the outlet opening.
The system may further comprise a monitor for showing an image captured by an image capturing means arranged at the distal tip unit.
The present disclosure may also relate to the following aspects, wherein each aspect of the following aspects may be independently and arbitrarily combined with any one of the above mentioned aspects and the claims:
The disclosure is explained in more detail below using preferred embodiments and referring to the accompanying figures.
The figures are schematic in nature and serve only to understand the disclosure. Identical elements are marked with the same reference signs. The features of the different embodiments can be interchanged among each other.
In
At the distal tip unit 4, image capturing means such as a miniature video camera and illuminating means such as light-emitting diodes or fibre optic light guides connected to a proximal source of light are arranged/installed, such that the patient's body cavity can be illuminated and inspected. An image captured by the image capturing means can be shown on a monitor M. The monitor M is provided separately from and connected with the endoscope 1. Further, the endoscope 1 is provided with the internal working channel which is formed within the endoscope shaft 3 and which is configured to guide a surgical instrument from the proximal endoscope handle 2 into the patient's body cavity. The user is therefore able to perform endoscopic examinations within the patient's body cavity.
A suction valve 5 is provided at the handle 2. Here, the suction valve 5 is inserted into the handle 2. One end of a suction tube 6 is connected to the suction valve 5. The other end of the suction tube 6 is connected to a suction device (a suction pump/vacuum pump) 7 that exerts a suction effect on the working channel via the suction valve 5.
The piston unit 9 accommodated in the internal guiding channel 10 comprises a piston 13, a button 14 that is fixed to the piston 13, a fixation ring 15 that is arranged immovably/stationary inside the housing 8 and a spring 16 that is positioned between the button 14 and the fixation ring 15. Although the spring 16 is positioned between the button 14 and the fixation ring 15 according to
The piston 13 includes a cylindrically shaped first (upper) piston portion 13a and a second (lower) piston portion 13b both merging into a transition area 13c arranged between the first piston portion 13a and the second piston portion 13b. The first piston portion 13a, the second piston portion 13b and the transition area 13c are integrally connected with each other.
The transition area 13c is provided with a radially outwardly protruding rim portion that is arranged between the first piston portion 13a and the second piston portion 13b. The radially outwardly protruding rim portion is urged against the fixation ring 15 by the spring 16 in the valve closed state.
The second piston portion 13b is provided with a cavity that interrupts a shell surface of the second piston portion 13b defining a first (side) opening 17 of the piston 13 and that interrupts a free end surface (bottom side) of the second piston portion 13b defining a second (bottom) opening 18 of the piston 13. The cavity between the first opening 17 and the second opening 18 defines a flow channel 19 of the piston 13 that allows a fluid flow between the first opening 17 and the second opening 18. The second opening 18 of the piston 13 is in fluid connection with the outlet opening 12 of the housing 8.
The fixation ring 15 comprises a ring-shaped/annular/circular ring-like portion 20 (afterwards simply called “ring-shaped portion 20”) from which a protruding portion 21 is extending. The protruding portion 21 contacts the second piston portion 13b. The ring-shaped portion 20 encircles/encloses/surrounds the first piston portion 13a. The piston 13 is movable relative to the ring-shaped portion 20 of the fixation ring 15. When the piston unit 9 is accommodated within the housing 8, the fixation ring 15 is preferably fixed within/to the housing 8.
The protruding portion 21 of the fixation ring 15 is designed as a spring-type finger in
In particular, the protruding portion 21 has a first (upper) portion extending essentially in an axial direction of the suction valve (along the piston 13) and a second (lower) portion being inclined with respect to the first (upper) portion towards the piston 13 (towards the second piston portion 13b) and contacting/pressing onto the piston 13 with a free end of the protruding portion 21.
The button 14 encompasses and covers the open end of the housing 8. For this purpose, the button 14 is formed like a hollow cylinder. The button 14 has a round button cover portion 22 and a cylindrical button shell portion 23 extending from the button cover portion 22. The button 14 is open at a free end that is opposed to the button cover portion 22. Hence, the button 14 defines an internal button cavity that is configured to accommodate the housing 8. The button 14 and the housing 8 are connectable with each other in a snap fit engaging manner. For this purpose, the open end of the button 14 is provided with an inwardly extending first snap-fit rim 24 and the (upper) end of the housing 8 that may be brought in contact with the button 14 is provided with an outwardly extending second snap-fit rim 25. When the piston unit 9 is connected to the housing 8, the first and the second snap-fit rims 24, 25 work together in such way that they limit a longitudinal movement of the piston 13 (unit) relative to the housing 8.
At its centre, the button cover portion 22 is provided with a circular hole 26 of such a size that it can accommodate the free (upper) end of the first piston portion 13a. In this way, the button 14 is fixable to the piston 13 such that the piston 13 is movable together with the button 14.
The spring 16 is interposed between the ring-shaped portion 20 of the fixation ring 15 and the button 14. In
In
Advantageously, the inlet opening 11 and the first opening 17 have the same diameter (at least where the inlet opening 11 and the first opening 17 are in flush contact) to prohibit fluid losses in the valve open state.
The suction valve 5 can be transitioned from the valve closed state to the valve open state in the following way:
First, a user, indicated by U, can manually press (with his finger) the button 14 towards the housing 8 (pressing force acting in a length direction of the suction valve 5). The pressing force of the user U must at least be so great that the elastic force of the spring 16 is overcome, in order to compress the spring 16. Associated with this, the button 14 moves (downwards) together with the piston 13. In this way, the piston 13 is moved/slided downwards inside the internal guiding channel 10 of the housing 8 until the outwardly protruding rim portion in the transition area 13c of the piston 13 contacts a stop provided inside the housing 8/the internal guiding channel 10. In this valve open state the first opening 17 and the inlet opening 11 are in flush contact with each other. Moreover, a sealing element 27 provided on an inner side of the button cover portion 22 contacts the (upper) free end of the housing 8. In the valve open state, the sealing element 27 seals the suction valve 5 against suctioning/drawing in air from the surroundings. The sealing element 27 is a separate part which may be fixed/attached, e.g. bonded/glued to the inner side of the button cover portion 22.
When the suction valve 5 shall again be transferred from the valve open state to the valve closed state, the user U simply has to stop pressing onto the button 14 (e.g. by simply releasing his finger). In this case, the spring 16 relaxes and its elastic force moves the button 14 and the piston 13 in a direction away from the housing 8 (outwardly) back into the valve closed state.
Moreover, it can be seen from
Furthermore, it can be seen from
As already described above, in the valve closed state, the piston 13, especially the planar surface 30 of the piston 13 contacting the correspondingly flat surface of the internal guiding channel 10, seals the inlet opening 11. It is an aim of this disclosure that the residual suction entering the suction valve 5 over the inlet opening 11 shall be reduced or even eliminated in the valve closed state. For this purpose an effective sealing between (the planar surface 30 of) the piston 13 and the inlet opening 11 is necessary. Against this background, in this disclosure, the fixation ring 15 is configured to urge the piston 13 against the inlet opening 11.
In this case, the second piston portion 13b is not just provided with an inclined portion 33 to allow the urging effect, but the end of the second piston portion 13b is further provided with a radially outwardly protruding flange portion 34 (afterwards simply called “flange portion”). The inclined portion 33 is arranged between the shell portion 32 and the flange portion 34. The inclined portion 33 and the flange portion 34 form together a holding portion. This holding portion can engage with the wedge-like protruding portion 21 of the fixation ring 15. The flange portion 34 may accommodate the wedge-like protruding portion 21 of the fixation ring 15. In the valve closed state, the wedge-like protruding portion 21 contacts the inclined portion 33 and may be held by the flange portion 34. As the inclined portion 33 extends outwardly starting from the shell portion 32, in the valve-closed state, the wedge-like protruding portion 21 of the fixation ring 15 exerts a pressing force onto the inclined portion 33 which is directed towards the inlet opening 11. Hence, the piston 13 is urged/pressed by (the wedge-like protruding portion 21 of) the fixation ring 15 against the inlet opening 11 and hence effectively seals the inlet opening 11 against an undesired residual suction. Thus, in the valve closed state, only a desired leakage flow C entering over the leakage slits 31 streams through the suction valve 5.
As already described above, at least two embodiments are imaginable to enable an urging effect of the fixation ring 15 onto the piston 13 towards the inlet opening 11. The first embodiment is that the protruding portion 21 of the fixation ring 15 is designed as a spring-type finger, urging the piston 13 towards the inlet opening by a spring force, as can be seen in
Moreover, in the embodiment shown in
In the second embodiment shown in
As already discussed above, in the first embodiment shown in
The second button portion 39 (made of the second material) comprises the integrated sealing portion 37, an inner circular portion 40 and an elongated portion 41. The inner circular portion 40 is at its center provided with the circular hole 26. The elongated portion 41 extends radially outwardly from the inner circular portion 40. The first button portion 38 is visually distinguishable from the second button portion 39. Preferably, the second button portion 39 is of another colour than the first button portion 38, especially the second button portion 39 is red as this colour indicates a user that this valve is used to control suction of the endoscope, whereas the first button portion 38 is of another colour than red. When the integrated sealing portion 37 is provided integrally with the button 14, no additional and/or separate sealing is necessary for such a suction valve 5. Hence, the assembly of such suction valve 5 can be simplified.
In
In
By providing the integrated sealing portion 37 in the button 14, the assembly process is eased as fewer components need to be handled. By providing a visual marker on the external surface of the button 14, the assembly process is eased as the assembler can readily infer the correct orientation of the button 14 for assembly with the remaining components of the valve. By providing a coloured external surface, the use of the button 14 is improved since the user can easily determine the function of the (suction) valve as the red colour is commonly used to indicate a suction function.
In
Furthermore, it can be seen in
The first and the second materials of the button 14 are preferably a first and a second (polymer) material. The first material may be a rigid polymer, e.g. acrylonitrile-butadiene-styrene (ABS) or polycarbonate (PC), which is used for the first button portion 38. The second material may be a flexible polymer able to form a sealing, such as thermoplastic polyurethane (TPU) or silicone, which is used for the second button portion 39. The button 14 may be manufactured using a multi (two)-component injection molding process.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2020 129 207.4 | Nov 2020 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/079276 | 10/21/2021 | WO |
