Patent Description:
Endoscopes have attained great acceptance within the medical community since they provide a means for performing procedures with minimal patient trauma while enabling the physician to view the internal anatomy of the patient. Over the years, numerous endoscopes have been developed and categorized according to specific applications, such as cystoscopy, colonoscopy, laparoscopy, and upper GI endoscopy and others. Endoscopes may be inserted into the body's natural orifices or through an incision in the skin.

An endoscope usually includes an elongated tubular shaft, rigid or flexible, having a video camera or a fiber optic lens assembly at its distal end. The shaft is connected to a handle which sometimes includes an ocular element for direct viewing. Viewing may also be possible via an external screen. Various surgical tools may be inserted through a working channel in the endoscope for performing different surgical procedures. Often, the endoscope also has fluid injectors ("jet") for cleaning a body cavity, such as the colon, into which they are inserted. A control section of the endoscope may include a suction cylinder and an air/water cylinder. Valves may be inserted into these cylinders to control various functions of the endoscope.

For example, an air/water valve for an endoscope may be inserted into the air/water cylinder or channel of the endoscope to provide air and water to the endoscope. When the air/water valve is in a first, normal position, air escapes from a vent in the valve. When insufflation is desired, an operator places a finger over the vent, which redirects the air towards the distal end of the endoscope, thus insufflating the organ that is being examined. When the operator engages the air/water valve (e.g. by depressing the valve), air is redirected to a water bottle and creates pressure in the bottle that causes water to flow towards the distal end of the endoscope.

<CIT> describes an air / water feeding conduit switching device for an endoscope.

<CIT> discloses a suction valve for an instrument which includes a valve insert secured in a valve housing. A first sleeve connects the interior of the valve housing to a first suction channel of the instrument; and a sealing membrane seals a first portion of the interior of the valve housing from the valve insert. The sealing membrane is fixed in the valve housing by the valve insert that includes a valve plunger for opening and closing the sealing membrane by movement in a first direction.

<CIT> discloses a switching operation valve which includes a piston body configured for a forward and backward movement in the axial direction and a sealing member, wherein the piston body is actuated by a thumb rest button.

In addition, a suction valve for the endoscope may be inserted into the suction cylinder or channel of the endoscope to provide suction to the endoscope. When the suction valve is in a first, normal position, air flow from the distal tip of the endoscope is blocked by the valve. When suction is desired, an operator engages the suction valve (e.g. by depressing the valve) to open the suction channel to create negative pressure that draws air or fluid into the opening of the instrument channel of the endoscope. When the operator releases the suction valve, the valve returns to its normal position blocking air flow and stops the suctioning.

After each use, an endoscope must be cleaned, disinfected, and sterilized to prevent the spread of disease, germs, bacteria and illness. Many components of an endoscope may be reusable, such as the air/water valve and suction valve and thus, must also be cleaned, disinfected, and/or sterilized between uses. Unfortunately, there is usually a great expense associated with maintaining sterility of the equipment. In addition, since reusable air/water and suction valves may be assembled from a combination of several metal, plastic, and/or rubber components there are significant costs associated with the manufacturing of reusable air/water valves.

Accordingly, there is a need for single-use or disposable air/water and suction valves that can be easily manufactured and assembled using a variety of materials for various components of the valves. Additionally, disposable air/water and suction valves do not require expensive materials to fabricate the valves, thereby eliminating the high cost of manufacturing suction valves from expensive materials.

The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods, which are meant to be exemplary and illustrative, not limiting in scope. The present application discloses numerous embodiments.

Optionally, the disposable air/water valve further comprises at least one bushing set within the at least one groove or a second groove, wherein said at least one bushing is configured to center said valve within a channel of an endoscope.

The shaft, seals, outer cap, inner ring, and button cap may comprise at least one of polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO, rubber, plastic, polycarbonate, ABS, MABS, and silicone.

The resilient member may comprise at least one of a corrosion resistant metal, polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, and styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO, rubber, and plastic.

Optionally, the shaft comprises machined steel and said button cap comprises plastic and said shaft is mechanically bonded to said button cap.

Optionally, the at least one hinge comprises a tine and barb wherein the barb has a width of less than <NUM> microns.

Optionally, the at least one hinge is configured to prevent vertical displacement of said at least one seal. Optionally, said at least one hinge is configured to generate an audible and tactile snap when said at least one hinge is connected to said corresponding mount, thereby indicating that the valve has been seated correctly.

Optionally, the at least one rib is configured to act as an edge stop to ensure said valve is centered on the mount and prevent a side loading from breaking said at least one seal.

Optionally, the outer cap and said inner ring with said at least one hinge and said at least one rib are molded as a single component.

The aforementioned and other embodiments of the present shall be described in greater depth in the drawings and detailed description provided below.

These and other features and advantages of the present invention will be appreciated, as they become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:.

The present specification is directed towards multiple embodiments. The following disclosure is provided in order to enable a person having ordinary skill in the art to practice the invention. Language used in this specification should not be interpreted as a general disavowal of any one specific embodiment or used to limit the claims beyond the meaning of the terms used therein. The general principles defined herein may be applied to other embodiments and applications without departing from the scope of the invention. Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention. In the description and claims of the application, each of the words "comprise" "include" and "have", and forms thereof, are not necessarily limited to members in a list with which the words may be associated.

It should be noted herein that any feature or component described in association with a specific embodiment may be used and implemented with any other embodiment unless clearly indicated otherwise.

As used herein, the indefinite articles "a" and "an" mean "at least one" or "one or more" unless the context clearly dictates otherwise.

It is noted that the term "endoscope" as mentioned to herein may refer particularly to colonoscopes and gastroscopes, according to some embodiments, but is not limited only to colonoscopes and gastroscopes. The term "endoscope" may refer to any instrument used to examine the interior of a hollow organ or cavity of the body.

<FIG> is a perspective view of a disposable air/water valve <NUM> in accordance with an embodiment of the present specification while <FIG>, <FIG> are respectively first, second and third cross-section views of the air/water valve <NUM>. Referring now to <FIG>, the air/water valve <NUM> comprises a stem or shaft <NUM> having a plurality of grooves <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and ridges <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> that are molded or machined, in various embodiments, as part of the shaft <NUM>. A plurality of seals <NUM>, <NUM>, and <NUM> may be set into the respective grooves <NUM>, <NUM>, <NUM> in accordance with some embodiments. A plurality of bushings <NUM>, <NUM> may be set into respective grooves <NUM>, <NUM> in accordance with some embodiments. The bushings <NUM>, <NUM> assist in centering the air/water valve <NUM> in a channel within an endoscope. In various embodiments, the bushings <NUM>, <NUM> are rigid or semi-rigid. In some embodiments, the air/water valve includes two bushings <NUM>, <NUM> positioned in grooves <NUM>, <NUM> respectively. In other embodiments, the air/water valve <NUM> includes only bushing <NUM> positioned in groove <NUM>. In other embodiments, the device does not have bushings and, instead, rely on ribs to center the valve appropriately. In addition, air/water valve <NUM> may also comprise inner ring <NUM>, outer cap <NUM>, resilient member <NUM> (<FIG>) such as, but not limited to, spring, rubber, elastic, and a button cap <NUM>.

In accordance with aspects of the present specification, the ridge <NUM> prevents unintentional removal of the seal <NUM> by providing an additional interference between the seal <NUM> and the shaft <NUM>. In various embodiments, the shaft <NUM> has a preferred travel direction (from the ridge <NUM> toward the end <NUM>) which enables an easier placement of the seal <NUM> than removal of the seal due to a direction of taper of the ridge <NUM>.

The components of air/water valve <NUM> may comprise at least one disposable material, including, but not limited to polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO (pluronics), rubber, plastic (e.g., polycarbonates), ABS, MABS, silicone, or combinations thereof. The resilient member <NUM> may be formed from a suitable material, such as corrosion resistant metal, polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, and styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO (pluronics), rubber, plastic, or combinations thereof.

It should be understood that the plurality of seals <NUM>, <NUM>, and <NUM> can be any member suitable for sealing a portion of the shaft <NUM>. The positioning of the seals corresponds to the water and air channels. The seals serve to prevent air from entering the water channel and to prevent air from exiting anywhere other than outside of the vent hold on the top of the shaft <NUM>. In some embodiments, the plurality of seals can be permanently attached to the shaft <NUM>, such as for example, by over-molding. In other embodiments, the plurality of seals can be removably attached to the shaft <NUM>, such as for example, by sliding the seal onto shaft <NUM>. Like other components of the air/water valve <NUM>, the plurality of seals can comprise polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, and styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO (pluronics), rubber, plastic (e.g., polycarbonates), ABS, MABS, silicone or combinations thereof.

In embodiments, the air/water valve <NUM>, when attached to or mounted onto an endoscope enables an air-flow rate of at least <NUM> cc/min from the tip section of the endoscope, wherein the tip section is capable of an overall output of about <NUM> cc/min at a pressure of <NUM> MPa (mega pascal). In some embodiments, the seal <NUM> is fabricated from a TPE (Thermoplastic Elastomer) material having a wall thickness of <NUM> and a <NUM> shore A hardness which enables an air-flow rate of at least <NUM> cc/min. In a preferred embodiment, the seal <NUM> is fabricated from a TPE material having a wall thickness of <NUM> and a <NUM> shore A hardness which enables an air-flow rate in a range of <NUM> to <NUM> cc/min. It should be appreciated that the wall thickness for the seal <NUM> may vary, in other embodiments, depending upon at least the type of material, hardness, geometry, molding conditions and number of support ribs. In some embodiments, the seal <NUM> includes, along its sides, a plurality of ribs. One embodiment of the seal <NUM> comprises four ribs <NUM> degrees apart from one another - two fully spanning the cross-section of the seal and the other two acting as filling channels. In one embodiment, the air-flow rate is a minimum of <NUM> cc per minute.

The shaft <NUM> provides an opening <NUM> and a passage or bore <NUM> that runs upwards through the shaft <NUM>, substantially along a longitudinal axis <NUM>, from the opening <NUM> to an end or vent <NUM>. The opening <NUM> lies along an axis <NUM> that is substantially perpendicular to the longitudinal axis <NUM>. When the end or vent <NUM> is not covered by an operator, air may travel via the opening <NUM> and up the passage or bore <NUM> to escape from the vent <NUM>.

The inner ring <NUM> has a diaphragm or collar <NUM> extending from an outer circumference of the inner ring <NUM> to the internal circumference of the outer cap <NUM>. The resilient member <NUM> is installed to lie between the inner ring <NUM> and the button cap <NUM> such that one end of the resilient member <NUM> is secured to the diaphragm or collar <NUM> and the other end to the button cap <NUM>. In some embodiments, the inner ring <NUM> is a monolithic internally molded part of the outer cap <NUM> while in other embodiments these may be two separate components. In various embodiments, the outer cap <NUM> (along with the inner ring <NUM> when molded as a monolithic part of the outer cap <NUM>) is molded using material of sufficient rigidity. In an embodiment, the outer cap <NUM> is molded from ABS having a Rockwell R hardness of <NUM> or hardness in the range of <NUM> to <NUM> shore D. The inner ring <NUM>, outer cap <NUM> and the button cap <NUM> respectively define internal bores for receiving the end or vent <NUM> of the shaft <NUM>. End <NUM> of the shaft <NUM> is placed through inner ring <NUM> and resilient member <NUM> and secured to the button cap <NUM> (as shown in <FIG>). When assembled, the diaphragm or collar <NUM> of the inner ring <NUM> rests upon the ridge <NUM>.

In accordance with an aspect of the present specification and as shown in <FIG>, an internal ring <NUM> of the button cap <NUM> is secured to the shaft <NUM>, at the end <NUM>, within a tapered notch, groove or recessed portion <NUM> (on the outer diameter of the shaft <NUM>) defined between a detent or protrusion <NUM> (towards the end <NUM>) and a ridge <NUM>. In an embodiment, the notch portion <NUM> is tapered at an angle 'A' with reference to a vertical line parallel to the longitudinal axis <NUM>.

Conventional valves typically use adhesive or welded joints to join or secure the button cap to the shaft. However, the securing mechanism of the present specification allows the use of dissimilar materials for the components such as the button cap <NUM> and the shaft <NUM>. For example, the shaft <NUM> may be of metal while the button cap <NUM> may be of plastic or the shaft <NUM> and the button cap <NUM> may both be of plastic yet of different melt temperatures. During a sterilization process, such as autoclaving, the plastic button cap <NUM> will melt and then become secured to shaft <NUM> as it dries post sterilization. Using dissimilar material for the button cap <NUM> and shaft <NUM> eliminates the need of matching material properties required in a gluing or welding process. Typically, materials must be selected so that they have similar melt temperatures (in the case of welding) or have surface properties conducive to adhesives. Eliminating such constraints allows the individual component materials of the button cap <NUM> and shaft <NUM> to be optimized for their specific purposes. For example, in some embodiments, the button cap is molded out of a lubricious plastic (ABS, Acetal, PTFE) that is cheap to manufacture. In some embodiments, the shaft <NUM> is machined out of steel and mechanically bonded to a plastic button. Use of a machined steel shaft allows for dimensional and geometric tolerances (diameter, straightness) that are difficult or impossible to meet with conventional molding. The shaft <NUM> and the button cap <NUM>, though manufactured of different materials or materials of different properties may be easily secured using the securing mechanism of the present specification. This further allows for optimization of materials for the shaft <NUM> and the button cap <NUM> and therefore the fabrication, manufacturing and assembly processes.

In accordance with another aspect of the present specification and as shown in <FIG>, <FIG>, a plurality of hooks <NUM> extend vertically downwards (substantially parallel to the longitudinal axis <NUM>) from the diaphragm or collar <NUM>. The plurality of hinges <NUM> enables attachment of the air/water valve <NUM> to a corresponding mount of an endoscope. In various embodiments, the corresponding mount of an endoscope comprises a flange which is surrounded by ribs <NUM> of the outer cap <NUM>, as described further below, and onto which the hinges <NUM> of the outer cap <NUM> snap and connect. Thus, ribs <NUM> and hinges <NUM> contained within outer cap <NUM> are used to connect the air/water valve to the flange of an endoscope. In various embodiments, the flange is an integral part of the endoscope and not single use or disposable. Use of the hinges <NUM> for attachment prevents vertical displacement of the seals and provides an audible and tactile positive locking 'snap' indicating to a user that the valve <NUM> is properly seated. Conventionally, over-molded TPE/TPU/Silicone in a two-part design is used for attaching the valve to the endoscope mount. However, the attachment mechanism enabled by the plurality of hinges <NUM> of the present specification is easier to manufacture while also providing a more secure connection to the endoscope during use. Specifically, inclusion of the hinges <NUM> reduces the overall part count. A single component is molded for the device of the present specification, whereas, in the prior art, a two-step molding process must be used or manual assembly of a rubber boot with a rigid plastic collar is required. A single mold results in shorter molding times and lower tooling costs. Elimination of a manual assembly step reduces overall labor input into the device.

In accordance with aspects of the present specification, it is desirable to configure or design the hinges or hooks <NUM> so that it achieves both a tactile, locking feel while the valve <NUM> is attached to the endoscope mount (using the hinges <NUM>) but is not so engaged that removing the valve <NUM> (such as for autoclaving, for example) poses a challenge. In other words, it is desired that the amount of insertion force required to engage the hinges or hooks <NUM> to the endoscope mount should be optimal that enables sufficient retention or attachment of the valve <NUM> to the endoscope mount without the retention being too strong to enable detachment of the valve <NUM> from the endoscope mount a challenge.

<FIG>, respectively illustrate first, second, third and fourth hinges or hooks <NUM>, <NUM>, 182i, 182j configured in accordance with various embodiments. In various embodiments, each hinge or hook <NUM> , <NUM>, 182i, 182j respectively comprises a barb <NUM>, <NUM>, <NUM>, <NUM> which is curved or angled (lead-in angle) on at least a portion and a tine <NUM>, <NUM>, <NUM>, <NUM>, which is a straight portion. Together, the barb and tine form an opening that is used to attach the valve <NUM> to an endoscope mount <NUM>. In an embodiment, the barb faces an inner diameter of the valve and the tine faces the outer diameter of the valve. In embodiments, the amount of insertion force required to engage a valve with an endoscope mount, degree of retention of the mounted valve, amount of depression force required to actuate the mounted valve and the amount of removal force required to disengage the valve from the endoscope mount are determined by at least a width 'w' and a lead-in angle Θ of the barb.

In one embodiment, as shown in <FIG>, the barb <NUM> has a width wg = <NUM> and a lead-in angle Θg = <NUM> degrees enabling the hinge or hook <NUM> to require a first amount of insertion/removal force.

In another embodiment, as shown in <FIG>, the barb <NUM> has a width wh = <NUM> and a compound lead-in angle Θh = <NUM>/<NUM> degrees (different lead-in angles for each side) enabling the hinge or hook <NUM> to require a second amount of insertion/removal force.

In another embodiment, as shown in <FIG>, the barb <NUM> has a width wi = <NUM> and a compound lead-in angle Θi = <NUM>/<NUM> degrees (different lead-in angles for each side) enabling the hinge or hook 182i to require a third amount of insertion/removal force.

In yet another embodiment, as shown in <FIG>, the barb <NUM> has a width wj = <NUM> and a lead-in angle Θj = <NUM> degrees enabling the hinge or hook 182j to require a fourth amount of insertion/removal force.

The amount of insertion/removal force corresponding to the hinges or hooks <NUM> through 182j varies as follows: first insertion/removal force > second insertion/removal force > third insertion/removal force > fourth insertion/removal force. Accordingly, the corresponding retention is highest for hinge or hook <NUM> progressively reducing for hinges or hooks <NUM>, 182i and lowest for hinge or hook 182j. Therefore, it can be generalized that the greater the width and the greater the compound lead-in angle, the greater the amount of force needed for insertion/removal.

As an example, air/water valve hinges or hooks having barb dimensions of <NUM> microns, <NUM> microns and <NUM> microns were tested to determine insertion force, removal force, and depression force. Note that a unit having <NUM> microns (or no barb) would have a very low retention force that would be insufficient for the purposes of the present invention. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the insertion force varied from <NUM> to <NUM> N. As shown in table <NUM> in <FIG>, for the <NUM> micron hooks, the insertion force varied from <NUM> to 13N. As shown in table <NUM> in <FIG>, for the <NUM> micron hooks, the insertion force varied from <NUM> to 12N. While there is some overlap, the general trend shows that the thinner the barb, the less the insertion force required.

As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the removal force varied from <NUM> to <NUM> N. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the removal force varied from <NUM> to <NUM> N. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the removal force varied from <NUM> to <NUM> N. Again, while there is some overlap, the general trend shows that the thinner the barb, the less the removal force required.

<FIG>, <FIG> and <FIG> are partial diagrams of a molded and machined air/water outer cap <NUM>. In an embodiment, as shown in <FIG>, an exemplary molded hook portion <NUM> has a width <NUM> of approximately <NUM>. Further, as shown in <FIG>, the thickness <NUM> of the hook <NUM> at a base portion <NUM> is approximately <NUM>. In an embodiment, it should be noted that the thickness <NUM> of the base portion <NUM> of the hook <NUM> ranges from <NUM> to <NUM>, as too thick of a hook will lead to stiffness and too thin of a hook will lead to a part that is not moldable.

As shown in <FIG>, the overall length or height <NUM> of the hook <NUM> is approximately <NUM>. Further, hook <NUM> travels a distance <NUM> of <NUM> when depressed or engaged. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the depression force varied from <NUM> to <NUM> N. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the depression force varied from <NUM> to <NUM> N. As shown in the table <NUM> in <FIG>, for the <NUM> micron hooks, the depression force varied from <NUM> to <NUM> N. Again, while there is some overlap, the general trend shows that the thinner the barb, the less the depression force required.

In one embodiment, the hook, having a barb and tine, comprises a barb having a width of less than <NUM> micron.

In accordance with still another aspect of the present specification and as shown in <FIG>, a plurality of positioning ribs <NUM> are formed along the inner circumference of the outer cap <NUM>. The ribs <NUM> extend vertically downwards (substantially parallel to the longitudinal axis <NUM>) along the inner circumference of the outer cap <NUM>. The ribs <NUM> enable the valve <NUM> to be centered on a valve well on the endoscope, aligning the shaft <NUM> with a center of the valve well and enabling precise vertical positioning of the plurality of seals within the valve well. The ribs <NUM> act as edge stops to ensure the valve <NUM> is centered on the mount and also prevent side loading from the user from breaking the seals on the valves.

In various embodiments, the shaft <NUM> of the disposable air/water valve <NUM> along with the plurality of ridges and grooves are of the same material as the shaft <NUM>. Similarly, the plurality of hinges or hooks <NUM> and ribs <NUM> may be molded as components of the inner ring <NUM> and the outer cap <NUM> (the inner ring <NUM> and outer cap <NUM> may also be molded as a single component) in accordance with various embodiments. It should be appreciated that the shaft <NUM>, the plurality of seals <NUM>, <NUM>, and <NUM>, inner ring <NUM>, outer cap <NUM> and button cap <NUM> may all be manufactured from dissimilar materials and still be easily assembled or secured together in accordance with various aspects of the present specification.

As described with respect to <FIG>, <FIG>, a plurality of hinges or hooks <NUM> extend vertically downwards (substantially parallel to the longitudinal axis <NUM>) from the diaphragm or collar <NUM>. The plurality of hinges or hooks <NUM> enables attachment of the air/water valve <NUM> to a corresponding mount of an endoscope. <FIG>, <FIG> illustrate an exemplary outer cap and associated components having a barb hook size of <NUM> microns with a lead-in angle of <NUM> degrees on each side. Outer cap <NUM> is shown in <FIG> and in an embodiment, has a height 'h' of approximately <NUM>. <FIG> shows the underside <NUM> or attachment portion of outer cap <NUM> that is used to attach the air/water valve to a corresponding mount of an endoscope. As shown in <FIG>, the attachment portion <NUM> may have a diameter of approximately <NUM>. <FIG> is a diagram showing the cross-section A-A <NUM> of outer cap <NUM> which is described in greater detail in <FIG>. As shown in <FIG>, cross section A-A <NUM> of the outer cap <NUM> shows an approximate distance 415a of <NUM> between hooks <NUM>, at a proximal end 420a, at the barbs <NUM> where the hook engages with a flange on the corresponding mount of an endoscope. At a distal end 420b, the approximate distance 415b between hooks <NUM> is <NUM>. Further, the approximate length <NUM> of each hook <NUM> is <NUM>.

<FIG> shows outer cap <NUM> with cross-section A-A <NUM> in a different view, as represented by <FIG>. As shown in <FIG>, the approximate distance <NUM> between barbs <NUM> of the hook <NUM> (where the hook engages with a flange on the corresponding mount of an endoscope) is <NUM> ± <NUM>. In one embodiment, the barbs <NUM> are machined at an angle <NUM> of approximately <NUM> ± <NUM> degrees with respect to a central longitudinal axis <NUM>. Further, a straight edge of barbs <NUM>, located just above the angular slanted portion, is machined at a distance of approximately <NUM> from the central longitudinal axis <NUM>. This detail is shown in <FIG> which represents an exploded view of cross section B-B of <FIG>. Further, a straight portion or tine <NUM> of hook <NUM> extends approximately <NUM> ± <NUM> farther than barbs <NUM>.

<FIG> is a flow chart illustrating a plurality of exemplary steps involved in operating an air /water valve of the present specification. Referring now to <FIG> and <FIG>, during operation the air/water valve <NUM> of the present specification may be positioned in an air/water cylinder of an endoscope. The endoscope provides an air channel for air and a water channel for water. The air and water channels are connected to a water bottle. The water channel extends into the fluid contained in the water bottle. When air/water valve <NUM> is placed in the air/water cylinder of the endoscope, the air/water valve <NUM> passes through both the air and water channels.

At step <NUM>, the air/water valve <NUM> is un-actuated, that is the button cap <NUM> is not depressed and the resilient member <NUM> is not compressed, and the vent <NUM> is open. As a result, at step <NUM> the air/water valve <NUM> allows air flow (provided by an air pump, for example) to enter the valve opening <NUM> and escape from the vent <NUM>. Note that disposable air/water valve <NUM> provides a plurality of seals (<NUM>, <NUM>, and <NUM>) that prevent air or water from leaking from the air or water channels. Also, the opening <NUM> of the air-water valve <NUM> is not aligned with the water channel and therefore there is no movement of water away from the water bottle, as the water channel is blocked.

At step <NUM>, the air/water valve <NUM> is unactuated, that is the button cap <NUM> is not depressed and the resilient member <NUM> is not compressed, but the vent <NUM> is closed or covered by an operator (using his finger, for example). As before, from the previous step <NUM>, the water channel is still blocked by the air/water valve <NUM>. Since the air vent <NUM> is now blocked by the operator, air from the air pump flows, at step <NUM>, past the air/water valve <NUM> towards a distal end of an endoscope. This allows the operator to insufflate a body cavity by blocking the air vent <NUM> of air/water valve <NUM> without actuating the valve.

At step <NUM>, the air/water valve <NUM> is actuated, that is the button cap <NUM> is depressed and the resilient member <NUM> is compressed, and the vent <NUM> continues to remain obstructed, closed or covered by the operator. Depressing the button cap <NUM> causes a downward force to be applied to the shaft <NUM> via ridge <NUM> and therefore the shaft <NUM> moves or is displaced downwards. Also, depressing the button cap <NUM> causes the resilient member <NUM> to compress against the supporting collar or diaphragm <NUM>.

The collar <NUM> rests against the endoscope mount and is therefore prevented from moving downwards (due to the depression of the button cap <NUM>). The downward movement or displacement of the shaft <NUM> causes the valve <NUM> to block the air channel and moves the opening <NUM> into the water channel, thereby creating a passageway for water to pass through the air/water valve <NUM>, at step <NUM>. Because the vent <NUM> is also blocked by the operator pressing down on the valve <NUM> (for depressing the button cap <NUM>), air flows instead into the water bottle via an air branched-channel connected to the water bottle. As the air pressure in water bottle increases, fluid is forced from the water bottle into the water channel, at step <NUM>. Thus, by actuating the air/water valve <NUM>, the operator causes water to flow towards the distal end of the endoscope for rinsing or irrigation.

When the operator stops depressing the button cap <NUM>, the compressed resilient member <NUM> begins to recoil or get uncompressed. The recoiling resilient member <NUM> applies an upward force to the button cap <NUM> that in turn transfers the upward force to the shaft <NUM> via the detent or protrusion <NUM>. This causes both the shaft <NUM> and the button cap <NUM> to be displaced upwards and return to the un-actuated position of the valve <NUM> of step <NUM>.

<FIG> is a perspective view of a disposable suction valve <NUM> in accordance with an embodiment of the present specification, <FIG> is a top view of the disposable suction valve <NUM>, <FIG> is a vertical cross-section view along an axis F-F of the disposable suction valve <NUM> of <FIG> while <FIG> is a horizontal cross-section view along an axis G-G of the disposable suction valve <NUM> of <FIG>. Referring now to <FIG>, the disposable suction valve <NUM> comprises a stem or shaft <NUM> of outer diameter 'D' and having a first groove or recess <NUM> (of a first diameter d<NUM>) and a second groove or recess <NUM> (of a second diameter d<NUM>) formed on the outer circumference of the shaft <NUM> and towards an end <NUM> of the shaft <NUM>; the first and second grooves <NUM>, <NUM> result in the formation of a first ridge <NUM> and a second ridge <NUM>; an inner ring <NUM> having a bore of a first internal diameter b<NUM> along a first length (parallel to the longitudinal axis F-F) of the bore and a second internal diameter b<NUM> along a second length l<NUM> (parallel to the longitudinal axis F-F) of the bore, wherein b<NUM> is approximately equal to d<NUM> and b<NUM> is approximately equal to 'D'; an outer cap <NUM>; a resilient member <NUM> such as, but not limited to, spring, rubber, elastic; and a button cap <NUM> having a central bore (along the longitudinal axis F-F).

The components of the disposable suction valve <NUM> may comprise disposable material, including, but not limited to polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO (pluronics), rubber, plastic (e.g., polycarbonates), ABS, MABS, silicone, or combinations thereof. The resilient member <NUM> may be formed from a suitable material, such as corrosion resistant metal, polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, and styrenic thermoplastic elastomer, carbon fiber, glass fiber, ceramics, methacrylates, poly (N-isopropylacrylamide), PEO-PPO-PEO (pluronics), rubber, plastic, or combinations thereof.

The shaft <NUM> provides an opening <NUM> and a passage or bore <NUM> that runs through the shaft <NUM>, substantially along the longitudinal axis F-F, from the opening <NUM> and vertically downwards to an end, opening or vent <NUM>. The opening <NUM> lies along an axis G-G that is substantially perpendicular to the longitudinal axis <NUM>. Fluid may pass horizontally through one side of the opening <NUM> and vertically downwards through the vent <NUM>. Opening <NUM> and vent <NUM> allow air or fluid to pass through a suction channel of the endoscope when the suction valve <NUM> is actuated.

The inner ring <NUM> has a diaphragm or collar <NUM> (<FIG>) extending from an outer circumference of the inner ring <NUM> to the internal circumference of the outer cap <NUM>. The resilient member <NUM> resides between the inner ring <NUM> and the button cap <NUM> such that one end of the resilient member <NUM> is secured to the diaphragm or collar <NUM> and the other end to the button cap <NUM>. In some embodiments, the inner ring <NUM> is a monolithic internally molded part of the outer cap <NUM> while in other embodiments these may be two separate components. The inner ring <NUM>, outer cap <NUM> and the button cap <NUM> respectively define internal bores for receiving the end <NUM> of the shaft <NUM>. End <NUM> of the shaft <NUM> is placed through inner ring <NUM> and resilient member <NUM> and secured to the button cap <NUM>. When assembled, the first length l<NUM> of the bore of the inner ring <NUM> fits over the second groove <NUM> (since, b<NUM> is approximately equal to d<NUM>) to rest upon the second ridge <NUM>.

In accordance with an aspect of the present specification and as shown in <FIG>, an internal ring <NUM> of the button cap <NUM> is secured to the shaft <NUM>, at the end <NUM>, within the first groove or recess <NUM> that has a taper defined between a detent or protrusion <NUM> (towards the end <NUM>) and the first ridge <NUM>. In an embodiment, the first groove or recess <NUM> is tapered at an angle 'N' with reference to a vertical line parallel to the longitudinal axis F-F. Conventional designs typically join or secure the button cap to the shaft using adhesive or welded joints. For optimal performance, the suction valve shaft requires a high degree of dimensional precision, generally not available to molded components. The securing mechanism of the present specification allows for a higher degree of dimensional precision through the use of dissimilar materials for the components such as the button cap <NUM> and the shaft <NUM>. For example, the shaft <NUM> may be of metal while the button cap <NUM> may be of plastic or the shaft <NUM> and the button cap <NUM> may both be of plastic yet of different melt temperatures. During a sterilization process, such as autoclaving, the plastic button cap <NUM> will melt and then become secured to shaft <NUM> as it dries post sterilization. Using dissimilar material for the button cap <NUM> and shaft <NUM> eliminates the need of matching material properties required in a gluing or welding process. Typically, materials must be selected so that they have similar melt temperatures (in the case of welding) or have surface properties conducive to adhesives. Eliminating such constraints allows the individual component materials of the button cap <NUM> and shaft <NUM> to be optimized for their specific purposes. For example, in some embodiments, the button cap is molded out of a lubricious plastic (ABS, Acetal, PTFE) that is cheap to manufacture. In some embodiments, the shaft <NUM> is machined out of steel and mechanically bonded to a plastic button. Use of a machined steel shaft allows for dimensional and geometric tolerances (diameter, straightness) that are difficult or impossible to meet with conventional molding. The shaft <NUM> and the button cap <NUM> though manufactured of different materials or materials of different properties may be easily secured using the securing mechanism of the present specification. This further allows optimization of materials for the shaft <NUM> and the button cap <NUM> and therefore their manufacturing and assembling processes.

In accordance with another aspect of the present specification and as shown in <FIG>, <FIG>, a plurality of hinges or hooks <NUM> extend vertically downwards (substantially parallel to the longitudinal axis F-F) from the diaphragm or collar <NUM>. The plurality of hinges or hooks <NUM> enables attachment of the suction valve <NUM> to a corresponding mount of the endoscope. In various embodiments, the corresponding mount of an endoscope comprises a flange which ribs <NUM> of the outer cap <NUM> surround, as described further below, and on to which the hinges <NUM> of the outer cap <NUM> snap and connect. In various embodiments, the flange is an integral part of the endoscope and not single use or disposable. The hinges or hooks <NUM> allow the collar component to be a single molded part, rather than an over-molded component or an assembly. Use of the hinges or hooks <NUM>, for attachment, provides an audible and tactile positive locking 'snap' indicating to the user that the valve <NUM> is properly seated. Typically, a two-part over-molded TPE/TPU/Silicone design is used for attaching the valve to the endoscope mount. However, the attachment mechanism enabled by the plurality of hinges <NUM> of the present specification is easier to manufacture while also providing a more secure connection to the endoscope during use. Specifically, inclusion of the hinges <NUM> reduces the overall part count. A single component is molded for the device of the present specification, whereas, in the prior art, a two-step molding process must be used or manual assembly of a rubber boot with a rigid plastic collar is required. A single mold results in shorter molding times and lower tooling costs. Elimination of a manual assembly step reduces overall labor input into the device.

In accordance with still another aspect of the present specification and as shown in <FIG>, <FIG>, a plurality of positioning ribs <NUM> are formed along the inner circumference of the outer cap <NUM>. The ribs <NUM> extend vertically downwards (substantially parallel to the longitudinal axis F-F) along the inner circumference of the outer cap <NUM>. The ribs <NUM> enable the valve <NUM> to be centered on a valve well on the endoscope, aligning the shaft <NUM> with a center of the valve well. The ribs <NUM> act as edge stops to ensure the valve <NUM> is centered on the mount.

In various embodiments, the plurality of hinges or hooks <NUM> and ribs <NUM> may be molded as components of the inner ring <NUM> and the outer cap <NUM> (the inner ring <NUM> and outer cap <NUM> may also be molded as a single component) in accordance with some embodiments. It should be appreciated that the shaft <NUM>, inner ring <NUM>, outer cap <NUM> and button cap <NUM> may all be manufactured from dissimilar materials and still be easily assembled or secured together in accordance with various aspects of the present specification.

<FIG> is a flow chart illustrating a plurality of exemplary steps involved in operating a suction valve of the present specification. Referring now to <FIG> and <FIG>, during operation the disposable suction valve <NUM> of the present specification may be placed into a suction cylinder of the endoscope. A suction channel of the endoscope is linked to the opening <NUM> (of the suction valve <NUM>) and leads to a distal end of an endoscope or leads toward the patient. The endoscope may be connected to a suction pump to create negative pressure in the suction channel when the suction valve <NUM> is actuated.

At step <NUM>, the suction valve <NUM> is unactuated, meaning that the button cap <NUM> is not depressed and the resilient member <NUM> is not compressed. As a result, at step <NUM>, the opening <NUM> remains out of position with the suction channel of the endoscope, thereby preventing the suction pump from creating negative pressure in the suction channel (that is, no suction is applied to the distal end of the endoscope).

At step <NUM>, the suction valve <NUM> is actuated - that is, the button cap <NUM> is depressed and the resilient member <NUM> is compressed. Depressing the button cap <NUM> causes a downward force to be applied to the shaft <NUM> via the first ridge <NUM> and therefore the shaft <NUM> moves or is displaced downwards. Also, depressing the button cap <NUM> causes compression of the resilient member <NUM> against the supporting collar or diaphragm <NUM>. The ring <NUM> rests against the second ridge <NUM> as a result of which the collar <NUM> is prevented from moving downwards (due to the depression of the button cap <NUM>). The downward movement or displacement of the shaft <NUM> causes the opening <NUM> to move into position with the suction channel from the distal end of the endoscope or from the patient. At step <NUM>, by aligning the opening <NUM> with the suction channel of the endoscope, a negative pressure created by the suction pump cause flow from the distal end of the endoscope towards the opening <NUM> (that is, suction is applied to the distal end of the endoscope). As a result, air and/or fluid may be suctioned from the distal end of the endoscope when the disposable suction valve <NUM> is in an actuated position.

When the suction valve <NUM> is released - that is, button cap <NUM> is not depressed the resilient member <NUM> recoils and applies an upward force to the button cap <NUM> that in turn transfers the upward force to the shaft <NUM> via the detent or protrusion <NUM>. This causes both the shaft <NUM> and the button cap <NUM> to be displaced upwards and return to the un-actuated position of the valve <NUM> of step <NUM>.

Claim 1:
A disposable air and water valve for an endoscope, comprising:
a shaft (<NUM>) having a passage (<NUM>) extending along a longitudinal axis (<NUM>) from a first opening (<NUM>) to a vent (<NUM>), wherein the shaft (<NUM>) has at least one groove (<NUM>-<NUM>), at least one ridge (<NUM>-<NUM>), and at least one protrusion (<NUM>) formed at the vent (<NUM>);
at least one seal (<NUM>, <NUM>, <NUM>) set within the at least one groove (<NUM>-<NUM>);
an outer cap (<NUM>);
an inner ring (<NUM>) having a diaphragm (<NUM>) that extends from an outer circumference of the inner ring (<NUM>) to an internal circumference of the outer cap (<NUM>), wherein at least one hook (<NUM>) extends substantially parallel to the longitudinal axis (<NUM>) from said diaphragm (<NUM>), wherein the at least one hook is configured to enable attachment of the disposable air and water valve to a corresponding mount of the endoscope and wherein at least one rib (<NUM>) is positioned along the internal circumference of the outer cap (<NUM>);
a button cap (<NUM>) having an internal ring (<NUM>) that is configured to securely attach to the shaft (<NUM>) by fitting into a notch near the vent (<NUM>) of the shaft (<NUM>); and
a resilient member (<NUM>) securely disposed between the button cap (<NUM>) and the diaphragm (<NUM>), wherein the outer cap (<NUM>), inner ring (<NUM>), and internal ring (<NUM>) of the button cap (<NUM>) define a central bore to accommodate said shaft (<NUM>).