HK1130714B - Needleless access port valves - Google Patents

Description

Needleless access port valve

Technical Field

The present invention relates generally to needleless access inlet valves, and more particularly to needleless access inlet valves having a piston that includes a slit along a piston section to create a fluid flow path.

Background

Needleless access inlet valves are widely used in the medical field to access IV lines and/or the internal organs of patients or patients. Generally, prior art valves utilize a valve housing in combination with a movable internal piston or plunger to control the flow of fluid through the valve. The piston or plunger may be moved by a syringe or medical implement to open the valve inlet to access the valve lumen. When delivering fluid through the valve, the fluid flow typically flows around the outside of the piston or plunger toward the outlet. When the syringe or medical implement is removed, the piston or plunger returns to its original position without assistance or with the assistance of a biasing means such as a spring or diaphragm.

In some prior art valves, when the syringe or medical instrument pushes on the piston or plunger, the piston or plunger is pierced by an internal piercing device, such as a needle tip. The needle tip typically incorporates one or more fluid passages to allow fluid flow through the pierced piston and subsequently through the fluid passage in the needle tip. In other prior art valves, an automatic flush or active flush feature is incorporated to push residual fluid in the valve lumen out of the outlet when the syringe or medical instrument is removed.

While prior art needleless access inlet valves are viable options for their intended application, there remains a need for alternative needleless access inlet valves.

Disclosure of Invention

The present invention is achieved by providing a valve assembly comprising a piston located inside a valve housing; the valve housing having an interior cavity, a bottom opening, and an inlet nozzle having an inlet and an interior wall surface; the piston comprises a flange, a neck section, a body section and a base; the piston further includes a slit having a first slit surface and a second slit surface extending through the flange in a direction from the inlet to the bottom opening and through at least a portion of the neck section below the flange, wherein the flange contacts an inner wall surface of the inlet nozzle to force at least a portion of the first and second slit surfaces into contact with each other.

The present invention also provides a valve assembly comprising a piston located inside a valve housing having an interior cavity, a bottom opening, and an inlet nozzle having an inlet and an interior wall surface; the piston comprises a flange, a neck section, a body section, an outer wall surface, and a base; the piston further includes a slit having a first slit surface and a second slit surface extending in a direction from the inlet to the bottom opening, wherein each slit surface includes a flange tip formed continuously with an end of the other slit surface.

In other aspects of the invention, a valve assembly is provided that includes a piston located within a valve housing, the piston including a flange, a neck section, a body section including an upper section and a lower section defining an internal cavity, an outer wall surface, and a base; the valve housing including an inlet nozzle having an inlet, a body section defining an interior cavity having an interior wall surface, and a bottom opening; a fluid space defined by a space between an outer wall surface of the piston and an inner wall surface of the valve housing for fluid to flow through the inlet nozzle and out the bottom opening; wherein the neck section of the piston includes a width and a slit formed on an outer wall surface of the piston through a portion of the width to flow a fluid.

The invention also includes methods of using and forming valve assemblies, including methods of manufacturing pistons for use in inlet valves, the methods comprising: molding a piston including a neck section having a reduced diameter compared to a body section, the body section defining an internal cavity; cutting a slit in the neck section; wherein the cutting step comprises a blade vibrated by an ultrasonic generator.

The invention also includes a valve assembly comprising a valve housing, a piston located within the valve housing, and a fitting secured to the valve housing; a fluid flow space defined by the piston outer surface and the valve housing inner surface when the piston moves from the first position to the axially compressed second position; a slit formed through a portion of the piston neck section and in fluid communication with the fluid flow space; wherein the antimicrobial composition is combined with at least one of the valve housing, the piston, and the fitting.

The invention also includes an actuator co-molded with the piston to open the slit.

Other aspects of the invention include providing internal depressions and/or ribs to create fluid flow paths in the interior cavity of the valve housing.

The present invention includes incorporating an antimicrobial agent within at least one of the piston, valve housing and nut fitting to control undesirable microbial growth. Exemplary agents include silver, gold, copper, and compounds thereof.

Other aspects of the invention include cutting a slit in the piston by a cutting method. Exemplary methods include thin blade cutting, laser cutting, water jet cutting, and combinations of blades and ultrasonic generator devices.

It should be appreciated that these and other features and advantages of the invention will be better understood with reference to the description, claims, and drawings.

Drawings

The drawings comprise:

FIG. 1 is a semi-schematic cross-sectional side view of a valve piston having an inlet actuator configured to open and close an upper section of the piston to create a fluid flow path in accordance with the present invention;

FIG. 2 is a semi-schematic cross-sectional side view of the valve piston of FIG. 1 with the inlet actuator in an open position;

FIG. 3 is a semi-schematic perspective view of an actuator according to the present invention;

FIG. 4 is a semi-schematic cross-sectional side view of the actuator mounted on a core rod for forming the piston;

FIG. 5 is a semi-schematic perspective view of the piston shown in FIG. 1, showing the actuator in an open position and various contours and dashed lines indicated by dashed-dotted lines;

FIG. 6 is a semi-schematic partial cross-sectional side view of the piston shown in FIG. 1, positioned inside a valve housing in a first closed position, and showing a partial view of a tip of a medical implement;

FIG. 7 is a semi-schematic partial cross-sectional side view of the valve of FIG. 6 with the piston pushed distally into the valve housing and the actuator in an open position;

FIG. 8 is a semi-schematic partial side view and partial cross-sectional view of a valve housing according to the present invention;

FIG. 9 is a semi-schematic partial side view of another valve housing according to the present invention;

FIG. 10 is a semi-schematic cross-sectional side view of an alternative valve piston having an inlet actuator configured to open and close the upper section of the piston to create a fluid flow path in accordance with the present invention;

FIG. 11 is a semi-schematic cross-sectional side view of the valve piston of FIG. 10 with the inlet actuator in an open position;

FIG. 12 is a semi-schematic perspective view of an alternative actuator according to the present invention;

FIG. 13 is a semi-schematic side view of yet another valve piston according to the present invention having a slit in the neck section of the piston;

FIG. 14 is a semi-schematic cross-sectional side view of the piston of FIG. 13 taken along line 14-14;

FIG. 15 is a semi-schematic partial cross-sectional side view of a valve assembly according to the present invention including the piston of FIG. 13 positioned inside a valve housing;

FIG. 16 is a semi-schematic partial cross-sectional side view of the valve assembly of FIG. 15 with the piston moved to a second position by the tip of the medical implement;

FIG. 17 is a semi-schematic side view of yet another valve piston according to the present invention having a slit in the piston neck section with a through bore;

FIG. 18 is a semi-schematic cross-sectional side view of the piston of FIG. 17 taken along line 18-18;

FIG. 19 is a semi-schematic cross-sectional side view of an alternative valve housing according to the present invention having a cross-bar at the lower neck section of the inlet nozzle;

FIG. 20 is a semi-schematic cross-sectional side view of the valve housing of FIG. 19 taken along line 20-20;

FIG. 21 is a semi-schematic partial perspective expanded view of the piston of FIG. 17 positioned within the chamber of the valve housing of FIG. 19;

FIG. 22 is a semi-schematic partial cross-sectional partial side view of an alternative valve assembly according to the present invention including the piston of FIG. 17 positioned inside the valve housing of FIG. 19 with the tip of the medical implement placed in contact with the top surface of the piston;

FIG. 22A is a semi-schematic partial cross-sectional partial side view of the valve assembly of FIG. 22 as viewed 90 degrees from the longitudinal axis of the valve housing;

FIG. 22B is a semi-schematic partial cross-sectional partial side view of the valve assembly of FIG. 22 with the piston moved to a second use position by the tip of the medical implement to open a fluid flow path from the inlet to the outlet of the valve assembly;

FIG. 23 is a semi-schematic cross-sectional side view of yet another alternative valve piston according to the present invention;

FIG. 24 is a semi-schematic partial cross-sectional partial side view of yet another alternative valve assembly according to the present invention including the piston of FIG. 23 positioned inside a valve housing having respective projections that mate with a pair of chambers positioned on the piston;

FIG. 25 is a semi-schematic cross-sectional side view of yet another alternative valve piston according to the present invention;

FIG. 26 is a semi-schematic cross-sectional side view of a nut fitting mated with a valve housing according to the present invention;

FIG. 27 is a cross-sectional side view of the nut fitting of FIG. 26 taken along line 27-27;

FIG. 28 is a semi-schematic partial cross-sectional partial side view of yet another alternative valve assembly according to the present invention including the piston of FIG. 25 positioned within a valve housing having the nut fitting of FIG. 26 attached to a lower end of the valve housing;

FIG. 29 is a semi-schematic partial cross-sectional partial side view of the valve assembly of FIG. 28 with the piston moved to a second position by a tip of a medical implement;

FIG. 30 is a semi-schematic cross-sectional side view of yet another valve piston in accordance with the present invention, as taken along line 30-30 of FIG. 32;

FIG. 31 is a semi-schematic side view of the piston of FIG. 30, showing a slit having an inverted Y-shaped configuration to provide a fluid flow path;

FIG. 32 is a semi-schematic side view of the piston of FIG. 31, as viewed after being rotated 90 degrees from the longitudinal axis of the piston;

FIG. 33 is a semi-schematic partial perspective view of the piston shown in FIGS. 30-32;

FIG. 34 is a semi-schematic partial cross-sectional partial perspective view of the piston of FIG. 30 including either of the valve housings of FIGS. 6 and 9 within a valve housing not shown;

FIG. 35 is a semi-schematic partial cross-sectional partial perspective view of the piston of FIG. 34 moved to a second position by a tip of a medical implement;

FIG. 36 is a semi-schematic partial cross-sectional partial perspective view of the piston of FIG. 34 moved to a second position by a tip of a medical implement; and

fig. 37 is a semi-schematic general view of an ultrasonic generator equipped with cutting blades for cutting a crack or slit in a piston.

Detailed Description

The following detailed description, in connection with the drawings, is intended to describe preferred embodiments of a needleless inlet valve or check valve (referred to herein as a "valve") in accordance with the present invention and is not intended to represent the only form in which the present invention may be constructed or utilized. The features and steps for constructing and using the valve of the present invention are described below in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. As shown elsewhere herein, like element numbers refer to the same or similar elements or features.

Referring now to FIG. 1, there is shown a semi-schematic cross-sectional side view of a valve piston or piston, generally designated 10, according to the present invention. As described below, the piston 10 is configured to regulate flow through a valve housing by expanding and sealing the valve housing to restrict flow between the inlet and outlet of the housing and by compressing or deforming to allow flow between the inlet and outlet. In one exemplary embodiment, the piston 10 includes a soft elastomer 12 including a first end 14 including a base or first flange 16 and a second end 18 including a second flange 20. For discussion purposes only, the first end 14 is referred to as the bottom end and the second end 18 is referred to as the adjustment end.

According to the invention, the first flange or base flange 16 has an outer diameter which is larger than the diameter of the body section 17 of the piston body 12. The upper surface 22, lower surface 24, and recessed lower surface 26 of the flange 16 are configured to be compressed between a nut fitting and a flange seat located on a valve housing, as described in U.S. Pat. No.6,871,838 (referred to herein as the "838 patent"), the contents of which are incorporated herein by reference.

In one exemplary embodiment, the body section 17 of the piston body 12 includes a generally straight cylindrical wall structure that extends between the base flange 16 and a first shoulder 28 having an acceptable slight taper, such as a draft angle. The lower neck section 30 projects proximally of the first shoulder 28, which has a smaller diameter than the main body section 17. The reduced section 32 (the enlarged section if viewed proximally-distally) extends proximally of the lower neck section 30 to an upper neck section 34 that is connected to the upper flange 20. When the piston 10 is positioned within a valve housing (not shown), the first shoulder 28 and the second flange 20 engage corresponding surfaces within the housing interior cavity to restrict flow around the piston outer surface, i.e., within the flow space defined by the valve housing inner surface and the piston outer surface, as described below.

The piston body 12 defines an inner cavity 36 having a lower chamber 38 and an upper chamber 40. In an exemplary embodiment, the interior cavity 36 is in fluid communication with ambient atmosphere. Thus, when the piston body is depressed and released, air enters and is discharged from the interior cavity 36 of the piston body 12.

In an exemplary embodiment, the piston 10 is made of a soft elastomeric material, with silicone being more preferred. Alternatively, the piston may be made of a thermoplastic elastomer (TPE) type, such as the Copolyamide (COPA) family of thermoplastic elastomers. In an exemplary embodiment, the COPA is available under the trademark COPAThe copolyamide thermoplastic elastomer of (1). However, other TPEs may also be used, including Thermoplastic Polyurethanes (TPUs), styrenic thermoplastic elastomers (TPOs), Thermoplastic Polyolefins (TPOs), Copolyesters (COPEs), and thermoplastic vulcanizate alloys (TPVs). Alternatively, the TPE may be chemically modifiedCrosslinking by radiation or to alter its properties. Alternatively, the piston may be made of a self-lubricating silicone material as disclosed in the' 838 patent. The piston 10 is preferably itself resilient in that it flexes when compressed and returns to substantially its original shape without the assistance of a spring when the load or force applied to the piston is removed. However, similar to the' 838 patent, previously incorporated by reference, a spring may be incorporated to facilitate recovery of the piston when the applied force is removed. When an external biasing member is used to assist the piston in returning from the second position to the less compressed first position, the piston body may be made of a soft material, not necessarily an elastic material. A less compressed state is determined relative to the body segment, which has less axial compression when in the first position than in the second position.

In one exemplary embodiment, an antimicrobial composition is provided to control or resist bacterial contamination within the valve, such as to reduce the amount of biofilm formation. The use of antimicrobial compositions in medical devices is well known in the art and is described, for example, in U.S. Pat. No.4,603,152 to Laurin et al, U.S. Pat. No.5,049,139 to Gilchrist, and U.S. Pat. No.5,782,808 to Folden. The use of antimicrobial compositions is also disclosed in Leinsing et al, publication Nos.2002/0133124A1 and 2003/0199835A 1. The contents of these patents and publications are incorporated herein by reference in their entirety. In one particular aspect of the invention, the silver zirconium phosphate is formulated as a molding compound for molding the piston 10, i.e., added to a TPE, silicone, or self-lubricating silicone material. The silver compound may be present in an amount of about 4% to about 10% by weight of the mixed injectant, with a preferred range of about 6% to about 8%. Alternatively or additionally, the antimicrobial composition is mixed in the material used to mold the valve housing and/or the nut fitting, as described below. Other antimicrobial agents that may be used with the components of the present invention include: silver, gold, platinum, copper and zinc. Antimicrobial metal compounds for use herein include oxides and salts, preferably silver and gold, such as: silver acetate, silver benzoate, silver carbonate, silver citrate, silver chloride, silver iodide, silver nitrate, silver oxide, silver sulfadiazine (silver sulfadiazine), gold chloride and gold oxide. Platinum compounds, such as chloroplatinic acid or chloroplatinic acid salts (e.g., sodium and calcium chloroplatinate), may also be used. Also, compounds of copper and zinc may be used, for example: oxides and salts of copper and zinc, such as those materials described above with respect to silver. A single physiological, antimicrobial metal compound or a combination of physiological, antimicrobial intermetallic compounds may be used. Still alternatively, a thin antimicrobial agent may be deposited on the wall surfaces of various valve members, as disclosed in the Folden' 808 patent.

In one exemplary embodiment, the piston has the following physical properties: a specific gravity of about 1.15, with a range of about 1.1 to about 1.2 being acceptable; a Shore A hardness of 50, wherein an acceptable hardness range is from about 40 to about 60; a minimum tensile strength of at least 600psi, with a more preferred minimum tensile strength of about 800 psi; an elongation of at least about 275%, with a minimum of about 350% being more preferred; and a tear strength of at least about 100ppi (pounds per inch), with 125ppi being more preferred. These values are exemplary properties of a particular piston embodiment and may vary for particular applications and material selections.

In an exemplary embodiment, an inlet actuator 42 is coupled to the upper neck section 34 of the piston body 12 to open and close a fluid path formed through the second flange 20 and at least a portion of the upper neck section 34. The inlet actuator 42 may be made of a rigid or semi-rigid thermoplastic material (e.g., glass-filled nylon) and molded into the piston body 12 using an overmolding process. The inlet actuator 42 has a generally V-shaped configuration and has an inner surface 46 and an outer surface 48 (fig. 2). Two opposing inlet plates 44 are formed on an inner surface 46 of the inlet actuator 42. A slit 50 is formed between the two inlet plates. In one exemplary embodiment, the two inlet plates 44 are made of the same material as the piston body 12 and are overmolded into the inlet actuator 42 and are formed integrally with the piston body. The soft inlet plate 44 forms a fluid tight seal along at least a portion of the slit 50 when the piston 10 is in a less compressed state, wherein the two plates are in contact with each other as shown in fig. 1, which corresponds to the piston first position when the piston is within the valve housing. Preferably, the slit 50 is aligned along the longitudinal axis of the piston. However, the slit may extend transverse to the longitudinal axis of the piston without departing from the spirit and scope of the present invention.

Fig. 2 is a semi-schematic cross-sectional side view of the piston 10 shown in fig. 1, with the inlet actuator 42 in an open configuration. In an exemplary embodiment, the inlet actuator 42 is naturally biased to the open position shown in FIG. 2, and the slits 50 separate to form gaps when no force is applied to the outer surface 48 of the actuator 42. In an exemplary embodiment, a ledge 52 on the outer surface 48 of the inlet actuator and a corresponding groove 52 on the inner surface of the upper neck section 34 combine to enhance the bonding or engagement between the inlet actuator and the piston body. However, multiple grooves and multiple projections, a reverse groove and projection configuration between the inlet actuator and the piston body, or a combination of projections and grooves on the inlet actuator and the piston body may be used without departing from the spirit and scope of the present invention.

Fig. 3 is a semi-schematic perspective view of an inlet actuator 42 according to the present invention. In one exemplary embodiment, the inlet actuator 42 includes an arcuate base 56 and two extension members 58 forming a V-shaped configuration with a more rounded apex at the arcuate base 56 than a typical V-shape. The generally V-shaped configuration separates the two projections 48 such that the two inner surfaces 46 generally do not contact each other, i.e., are remote from each other.

FIG. 4 is a semi-schematic cross-sectional side view of the inlet actuator 42 mounted on a core rod 60. The core pin 60 forms the inner cavity profile of the piston body 12 and is configured to cooperate with the mold and the inlet actuator 42 to form the piston 10. The core pin 60 includes a receiving portion 62 for receiving and retaining the inlet actuator 42 in a slightly compressed state, wherein the ends 64 of the two extensions 58 are moved closer to each other than in the normally expanded state shown in FIG. 3.

Fig. 5 is a semi-schematic perspective view of the piston 10 shown in fig. 2, shown in a dashed line representing a dotted line. When no inward force is applied to the two extensions 58 of the inlet actuator 42 (i.e., when the extensions 58 are not constrained), they expand open to enlarge the slit 50 and create the gap 66. Thus, if fluids are located at the ends 64 of the projections 58, they will flow between and out of the side gaps 66 of the fracture 50.

FIG. 6 is a semi-schematic partial side view of the piston 10 of FIG. 1 positioned inside a valve housing 68 in a closed or first position and showing a medical instrument tip 69, such as a syringe or tube adapter. The valve housing 68 includes an inlet nozzle 70 defining an inlet 72. In one exemplary embodiment, the inlet comprises a luer type inlet that includes external threads 74, but may be unthreaded, i.e., a luer slip fitting. The inner surface 76 of the inlet nozzle 70 defines a circumference sized much smaller than the diameter of the second flange 20 to compress the second flange from the position shown in fig. 2 to the closed position shown in fig. 1. In one exemplary embodiment, the inner diameter ID of the inlet nozzle is about 0.5 mil to about 8 mils smaller than the normal closed diameter of the second flange 20, which is preferably about 0.1 mil to about 3 mils. The relative size between the inner diameter of the inlet nozzle and the normally closed diameter of the second flange 20 forms a seal at the inlet 72 to terminate fluid communication between the inlet 72 and the outlet (not shown) of the valve assembly 78. Although fig. 6 shows the reduced section 32 between the lower neck section 30 and the upper neck section 34 of the piston 10 spaced from the shoulder 70 in the interior cavity of the inlet nozzle 70, in an exemplary embodiment, the two contact each other to provide a second sealing point.

FIG. 7 is a semi-schematic partial cross-sectional side view of the valve assembly 78 of FIG. 6 in a second or open position with the tip 69 of the medical implement inserted into the inlet lumen of the inlet nozzle 70. The tip 69 applies downward pressure to the inlet actuator 42 and the piston body 12 and pushes both distally into the interior cavity of the valve housing 68. As described in the' 838 patent, previously incorporated by reference, when the piston 10 is moved to its second position, the piston body 12 contracts into an arbitrary fold under the pressure of the tip 69. In one exemplary embodiment, the retracted piston body changes the space occupied by the piston by a sufficient amount to produce a negative bolus effect or negative flush represented by a small amount of fluid entering the chamber of the valve when the piston moves to its second position.

The inlet actuator 42 moves to an enlarged lower neck section 82 of the valve housing 69 that defines an inner perimeter 84 that is larger than the inner perimeter 76 of the inlet nozzle upper section 70. The larger lower neck section 82 provides sufficient space to enable the inlet actuator 42 to expand, which separates the slits 50 to create a flow path or gap 66 for fluid to flow from or to the medical instrument. Assuming that fluid is delivered by the medical instrument, the fluid flow will exit the tip 69 through the gap 66 formed at the fracture 50, exiting through both sides of the fracture. The fluid then flows in the space between the inner wall surface of the valve housing 68 and the outer surface of the piston 10 and out the valve outlet (not shown). When the tip 69 is removed from the inlet nozzle 70, the piston 10 expands due to the resilient nature of the material forming the piston 10, returning to the position shown in fig. 6. In one exemplary embodiment, a positive bolus effect (positive bolus effect) is produced when the piston 10 is expanded to its first position, characterized by a small amount of fluid being pushed out of the outlet from the valve interior.

FIG. 8 is a semi-schematic partially cut-away side view of an exemplary valve housing 68 according to the present invention, but without the piston. Referring to FIG. 8 in addition to FIG. 7, the interior cavity 86 has another elongated interior perimeter 88 defined by a body section 90 of the valve housing 68. The lower elongated inner periphery 88 includes a lower generally circular or curved shoulder 92. In an exemplary embodiment, the curved shoulder 92 cooperates with the first shoulder 28 on the piston body 12 to provide another sealing point.

In one exemplary embodiment, the inner periphery 88 of the main body segment 90 has a smooth surface. The inner periphery 88 defines a major inner diameter 89 having a generally constant diameter over a majority of the body segment, which in one example is generally constant only from the end of the lower shoulder segment 92 to the approximate intersection of the body segment 90 and the skirt 94. In one exemplary embodiment, the major inner diameter 89 is sized to be substantially larger than the diameter of the main body section 17 of the piston 10 (FIG. 1) such that the fluid flow delivered through the inlet 72 of the valve housing 68 or from the outlet of the valve housing toward the inlet for sampling through the valve has sufficient fluid flow space to flow out of the valve outlet 100.

Externally, the valve housing 68 has a plurality of ribs 93, which in one exemplary embodiment include four equally spaced ribs. A downwardly extending skirt 94 depends from the body section 90 and terminates in a lower opening 96 for receiving a nut fitting 98. As described in the' 838 patent, the nut fitting 98 includes an outlet 100 for egress of fluids delivered through the inlet 72 and a threaded collar 102 for threaded engagement with a second medical implement (not shown), which may be a tube adaptor, a catheter, or the like. Nut fitting 98 may be ultrasonically welded or alternatively bonded to skirt 94 by welding or bonding a flange 104 on nut fitting 98 to the end edge of skirt 94.

FIG. 9 is a semi-schematic cross-sectional side view of an alternative valve housing 106 according to the present invention. In an exemplary embodiment, the valve housing 106 includes an inlet nozzle 108 defining the inlet 72, a main body segment 112, and a skirt 114 depending therefrom having an end edge 116 defining a lower housing opening 118.

Internally, the valve housing 106 includes an upper inlet section or upper neck section 120, a tapered section or lower neck section 122, a main inner body section 124 and an inner skirt section 126. In an exemplary embodiment, the inner body section 124 includes a plurality of raised ribs 128 that project above the inner wall surface of the inner body section 124 and a plurality of depressions 130 that are recessed below the inner wall surface of the inner body section. The raised ribs 128 and depressions 130 provide a flow path or channel for fluid flow from the inlet to the outlet of the valve, with a space between the inlet and outlet defined by the valve housing inner wall surface and the piston outer surface.

In an exemplary embodiment, the skirt 114 has a plurality of undercut recesses 132 on an inner wall surface 134. The lower recess 132 is preferably aligned with the upper recess 130 such that fluid flow through the upper recess follows its path to the outlet to the lower recess. In one exemplary embodiment, there are eight projecting ribs 128, eight upper depressions 130, and eight lower depressions 132. The ribs and depressions are preferably equally spaced from each other. Also shown is a locating means 117 formed on the skirt for locating the nut fitting. In one exemplary embodiment, there are three spaced apart positioning devices.

Fig. 10 is a semi-schematic cross-sectional side view of an alternative piston 136 according to the present invention. The piston 136 is configured to work with a valve housing, as shown in fig. 6-9, to regulate fluid flow from the valve housing inlet to the outlet or vice versa. In an exemplary embodiment, piston 136 includes a piston body 138 defining an interior cavity 142 and an inlet actuator 140. The piston body 138 is similar to that disclosed in fig. 1, 2 and 5, except for a few differences. In the present embodiment, the upper neck section 34, the lower neck section 30, and a portion of the body section 17 are solid forms made of the same material as the piston wall, which are collectively referred to herein as the upper piston core 144. The body section 17 defining the chamber 142 is referred to herein as a flexible, resilient piston base 146. Similar to the inlet actuator 42 of the embodiment shown in FIG. 1, the inlet actuator 140 in this embodiment includes a projection 148 configured to emerge through the upper neck section 34.

When the piston 136 is installed within the valve housing and compressed during operation, the soft, resilient piston base 146 is configured to bend and twist in any manner to accommodate the tip of the medical instrument. In one exemplary embodiment, the soft, resilient piston base 146 is configured to spring back without the aid of a spring or other independent biasing member when the medical instrument is removed. By selecting an elastomer or TPE with sufficient resilience, wall thickness and hardness, the soft piston base 146 can have sufficient spring characteristics that allow the piston base to spring back without a separate spring. However, it will be apparent to those of ordinary skill in the art that a coil spring may be placed in the interior 142 to facilitate piston recovery, as described in the' 838 patent.

FIG. 11 is a cross-sectional side view of the piston 136 of FIG. 10, showing the inlet actuator 140 positioned outside the valve housing in a normal state. As best shown, the two extensions 58 are spaced from each other, which open a gap for fluid flow at the slit 50, as previously described.

Figure 12 is a semi-schematic perspective view of the inlet actuator shown in figures 10 and 11. Both extensions 58 include extension legs 150. In one exemplary embodiment, the piston body 138 is molded over the inlet actuator 140 by first placing the inlet actuator into a mold cavity, placing a core pin therein, placing a thin sheet between the two extensions, and then injection molding the mold with an elastomer or TPE. After the injection process, the piston is removed and a crack 50 is formed in the overmolding process.

FIG. 13 is a semi-schematic side view of yet another piston embodiment 152 in accordance with the present invention. In an exemplary embodiment, the piston 152 includes a lower flange 16, a body section 154, and a neck section 156 that includes an upper flange 158. A slit 160 is provided generally along the center of the neck section 156 to define two piston neck extensions 157. The slit 160 extends between an upper top surface 162 of the piston and a shoulder 164 at the upper edge of the body section 154. The slit 160 defines a slit having a flat surface that can be opened or closed to form a gap depending on the position of the piston 152 when inside the valve housing. Preferably, the slit 160 is aligned along the longitudinal axis of the piston. However, the slit 160 may extend transverse to the longitudinal axis of the piston without departing from the spirit and scope of the present invention.

Figure 14 is a cross-sectional side view of the piston of figure 13 taken along line 14-14. In one exemplary embodiment, the neck section 156 is molded as a solid structure integral with the slit 160, which is formed by a cutting process after the molding step. Exemplary cutting methods include cutting the neck section with a thin blade, by laser cutting, or by water jet cutting. Referring to FIG. 37, in one embodiment of the invention, the slit 160 is cut using a thin blade 290 having a sharp edge, preferably made of a rare metal such as titanium, having a thickness of about 0.015 inch to about 0.03 inch. The blade is mounted to a coupler or shaft 292 which is connected to a prior art ultrasonic generator 294, which preferably has an operating range of about 20kHz to about 40 kHz. An exemplary generator includes the Branson2000aed model. The piston 152 is then placed in a fixture 296, such as a base or cylinder, with the neck section directly adjacent the blade 290. The ultrasonic generator 294 is actuated while the blade is moved coaxially into the piston if the piston is held in a vertical orientation, or perpendicular to the piston centerline if the piston is held in a horizontal orientation. When the slit 160 is made, the blade is no longer driven and is withdrawn from the piston. Alternatively, the vibrating blade may remain stationary and a piston mounted on a base or cylinder 296 moves into the vibrating blade to create the slit.

The solid upper body segment 166 extends at the end of the neck segment 156 with a stop pin 168 extending distally thereof into the internal cavity 142 of the body segment 154. The stop pin 168 is configured to limit over-insertion of the medical instrument by providing a physical stop and limit the amount of inward retraction of the piston wall into the lumen 142 when the medical instrument is bent from above and the nut fitting is bent from below.

FIG. 15 is a partial cross-sectional side view of the piston 152 installed within the valve housing 68 to form a valve assembly 170. The piston 152 is shown in a first or closed position wherein the upper flange 158 is compressed against an inner wall surface of the inlet nozzle 70, which serves to seal the valve 170 and close fluid communication between the inlet 72 and the outlet (not shown). The piston shoulder 164 also abuts the lower shoulder 92 of the valve housing 68 to provide another sealing point.

Fig. 16 is a semi-schematic partial cross-sectional side view of the valve assembly 170 of fig. 15, wherein the valve assembly is urged to a second or use position by the tip 69 of a medical instrument. The tip 69 pushes the upper top surface 162 of the piston 152 into the inner section 84 of the enlarged lower section 82 of the inlet nozzle 70. Due to the larger interior space at the enlarged lower section 82, the two piston neck extensions 157 separate, which may be referred to as a bending effect caused by the medical instrument and the stop pin 168, thereby forming the gap 66 at the split 50. At this point, fluid delivered by the medical implement flows out of the tip 69 through the slit 50 and then around the outer surface of the piston 152 and the inner surface of the valve housing 68. Conversely, if a sample is to be taken, the fluid will flow within the space defined by the inner surface of the valve housing and the outer surface of the piston, then through the slit 50 and into the tip 69.

When the tip 69 is removed from the inlet nozzle 70, the piston 152 automatically moves from the second position (fig. 16) to the first position (15). The piston body section 154 automatically recovers due to its inherent elastic properties. Alternatively, as previously described, a coil spring may be used to facilitate recovery.

Fig. 17 is a semi-schematic cross-sectional side view of yet another piston 172 according to the present invention. In an exemplary embodiment, the optional piston 172 is similar to the piston 152 disclosed in fig. 13 and 14, except for some differences. For example, the piston 172 has a slit 160 defining a split and dividing the neck section 156 into two piston neck extensions 157, and a stop pin 168. In the present embodiment, a through-hole 174 having a polygonal cross-section is formed along at least a portion of the through-hole. In a preferred embodiment, the through-hole 174 is hexagonal such that two vertices 176 are longitudinally aligned in the same direction as the vertical slots 160. The through-hole 174 is formed such that half of the through-hole is formed on one piston neck extension 157 and the other half is formed on the other piston neck extension.

Referring to fig. 18, a cross-sectional side view of the piston 172 of fig. 17 taken along line 18-18 is shown. In one exemplary embodiment, the through-hole 174 is formed by molding a tapered upper surface 178 and a molded tapered lower surface 180 that are separated from each other by a side surface 182. The tapered upper surface 178 is configured to abut a cross rib located inside the valve housing for exerting a pair of force components on the tapered surface to push the piston neck extension 157 outward, as described below. The tapered lower surface section 180 has a similar profile to the lower surface of the cross-rib, as described below, and is configured to surround the lower surface when in the piston first position.

In an exemplary embodiment, the length of the tapered upper surface 178 is shorter than the length of the tapered lower surface 180. This relative sizing creates exposed via segments 185 at each end thereof. The two exposed ends 185 (shown in FIG. 21) are configured to receive respective ends of a crossbar located inside the valve housing. However, it will be apparent to those of ordinary skill in the art that the two exposed ends 185 (FIG. 21) differ in shape, size and contour depending on the shape, size and contour of the crossbar, which may vary at the discretion of the designer.

FIG. 19 is a semi-schematic cross-sectional side view of a valve housing 184 according to the present invention. The valve housing 184 is similar to the valve housing described with reference to fig. 8 and 9, except for some differences. In a different aspect, the cross-bar 186 is incorporated within the interior cavity of the enlarged lower section 82 of the inlet nozzle 70. In an exemplary embodiment, the crossbar 186 includes a generally circular upper middle section 188 and a V-shaped bottom section 190 that includes an apex. The cross-bar is preferably integrally molded with the valve housing 184.

In an exemplary embodiment, the inner periphery 88 of the body segment 90 includes a flat or smooth inner wall surface. However, the protruding ribs or the flow recesses or both may be included without departing from the spirit and scope of the present invention. In an exemplary embodiment, a plurality of lower recesses 132 are formed on the skirt 94 of the valve housing.

FIG. 20 is a cross-sectional side view of the valve housing 184 of FIG. 19 taken along line 20-20. The cross-bar 186 has a circular upper middle section 188 (as previously described) and two angled ends 190 that correspond to the angled ends 192 located on the through-bore 174 of the piston 172. It will be apparent to those of ordinary skill in the art that the angled ends 190, 192 on the valve housing and piston can be modified or eliminated without departing from the spirit and scope of the present invention, such as having the circular mid-section 188 extend the entire length of the cross-bar. Still alternatively, crossbars with a single apex, different curvatures, or multiple apexes may be included.

FIG. 21 is a semi-schematic partial perspective cut-away view of the piston 172 of FIG. 18 partially positioned within the valve housing of FIG. 20. The piston 172 is configured to be inserted into the interior cavity 86 of the valve housing 184 by passing the neck section 156 through the end opening 96 of the valve housing 184 and aligning the slit 160 with the cross-bar 186. The piston is then pushed proximally until the cross-bar is seated in the through-hole 174. When installed, the two angled ends 190 of the cross-bar are supported within the two exposed through-hole areas 185. In one exemplary embodiment, a rod (not shown) is used to push the piston 172 within the housing. The rod may pass through the open end 194 (fig. 17) of the piston and push against the stop pin 168.

FIG. 22 is a side view, partially in cross-section, of a valve assembly 196 including the piston 172, the valve housing 184 and the nut fitting 98. The piston 172 is shown in a first or closed position, wherein the upper flange 158 presses against the inner surface 76 of the inlet nozzle 70 to squeeze the two piston neck sections 157 together and shut off fluid flow between the inlet 72 and the outlet 100. The shoulder 164 of the piston 172 abuts the lower shoulder 92 in the valve housing interior cavity 86 to form a second seal.

Fig. 22A is a side view, partially in section, of the valve assembly 196 of fig. 22, as viewed in a vertical viewing plane.

Fig. 22B is a side elevational view, partially in cross-section, of the valve assembly 196 illustrated in fig. 22 and 22A in a second or use position. The tip 69 of the medical implement is inserted into the bore of the inlet nozzle 70 to compress the piston 172. As previously described, the force applied by the tip causes the body section 154 (FIG. 17) of the piston to bend and twist into an arbitrary fold. At the same time, the slit 160 is pushed onto the cross bar 186, which then separates the slit 160 to enlarge the gap 66. The fluid F delivered by the medical implement flows through the tip 69 and through the gap 66 formed at the fracture 50 before flowing out through the sides of the fracture and past the outer surface of the piston 172 toward the outlet 100. After the fluid flows through the medical implement, the tip 69 is removed from the inlet nozzle 70 while removing the force on the top surface of the piston. This allows the piston 172 to return to its less compressed state as shown in fig. 22 and 22A.

As previously described, the piston 172 automatically recoils and moves from the second position to the first position without assistance from a spring or independent biasing member. However, a spring or separate biasing member may be placed in the interior cavity 142 of the piston 172 to facilitate resetting of the piston from the second position to the first position.

Fig. 23 is a semi-schematic cross-sectional side view of yet another piston 198 in accordance with the present invention. This piston 198 embodiment has many similarities to the piston 17 shown in fig. 17, 18, 20 and 22. However, while the piston 172 is shown in FIGS. 17, 18, 20 and 22 as having a through bore 174, the present piston 198 embodiment has a dividing wall 202 located at the through bore to define two chambers 200. The two upper ends 204 of the two chambers 200 are likewise modified to terminate in simple rounded corners. In one exemplary embodiment, the dividing wall 202 includes two tapered wall surfaces 206 that extend outward to cover the wall from a proximal position to a distal position. Each chamber 200 includes a tapered upper surface 178 and a tapered lower surface 180, similar to the through-holes 174 disclosed in fig. 18.

FIG. 24 is a side view, partially in cross-section, of a valve assembly 208 according to the present invention, including the piston 198 of FIG. 23 mounted inside a valve housing 210. In an exemplary embodiment, the valve housing 210 is similar to the valve housing described above with reference to fig. 19 and 20, except for some differences. In this embodiment, at the junction of the inlet nozzle 70 and the main body section 90, the housing internal cavity includes two rib extensions 212 instead of the continuous crossbar 186. The two rib extensions 212 are sized to extend into the two cavities 200 (fig. 23) and the two cavities are sized to receive the two rib extensions.

In use, the tip 69 of the medical instrument is inserted into the chamber defined by the inlet nozzle 70 and a force is then applied to the piston 198. The downward force on the piston 198 pushes the two chambers 200 against the two rib protrusions 212, which then act on the tapered upper surfaces 178 of the two chambers to split the neck section 156 along the slit 160 to open the gap at the slit. The gap provides a fluid flow path for fluid to flow between the inlet 72 and the outlet 110.

After injection and removal of the tip 69 from the inlet nozzle, the piston 70 is restored to its less compressed state by moving from the second position to the first position. As previously mentioned, a spring or separate resilient member may optionally be used with the piston 198 to facilitate recovery after the tip 69 is removed.

Fig. 25 is a semi-schematic cross-sectional side view of yet another alternative piston 214 in accordance with the present invention. In one exemplary embodiment, the piston 214 includes a slit 160 that divides the neck section 156 into two piston neck extensions 157, as with the other previously described pistons. The piston 214 also includes a body section 154 and a lower flange 16. The body segment 154 defines an interior cavity 142 that includes an upper wall surface 216 and a needle tip aperture 218. A spike bore 218 extends proximally from the upper wall surface through the upper body section 166 and a portion of the lower neck section 30.

In a preferred embodiment, the needle tip bore 218 terminates in an apex 220, and the apex tip communicates with the slit 160 when the latter is open. In one exemplary embodiment, the bore 218 comprises a cylindrical bore of a single diameter. Preferably, however, one or more reduced neck segments 222 are incorporated into bore 218 to act as a sealing ring around the actuating pin, as described below.

Fig. 26 is a semi-schematic cross-sectional side view of a nut fitting 224 according to the present invention. In an exemplary embodiment, the nut fitting 224 is similar to the nut fitting disclosed in the' 838 patent except for a central projection 226 having an elongated actuating pin 228 with a rounded tip 230. Other features of the nut fitting 224 include a circular groove 232, a raised surface 234, a seal seat 236 including an optional projection 238, similar to the raised surface flange. More distally, the nut fitting 224 includes two spaced apart fluid passages 240, a skirt 246 including one or more locating members 242, a flange 244, and a discharge nozzle 248 including a lumen 250.

Fig. 27 is a cross-sectional side view of the nut fitting 224 of fig. 26 taken along line 21-21. The nut fitting includes a pair of vent holes 252 to vent air present in the interior chamber 142 of the piston 214 when the piston is compressed by the tip of the medical instrument, as described in the' 838 patent. In one exemplary embodiment, the two vent holes 252 are 180 degrees apart from each other and are each located between two liquid channels 240, which are also 180 degrees apart from each other.

FIG. 28 is a semi-schematic partially cut-away side view of a valve assembly 254 according to the present invention including the piston 214 of FIG. 25 disposed within the valve housing 184, wherein the nut fitting 224 of FIGS. 26 and 27 is secured to the lower opening 96 of the valve housing 68. In the piston first position shown, the upper flange 158 seals against the inner surface of the inlet nozzle and the piston shoulder 164 seals against the lower shoulder 92 on the housing to terminate fluid communication between the inlet 72 and the outlet 100. The two piston neck extensions 157 squeeze together to close the gap formed at the slit 160.

The elongated actuator pin 228 is disposed within the needle tip bore 218 of the plunger with a rounded tip 230 adjacent the distal most end of the slit 160. The holes 218 are preferably sized to be neutral (i.e., no interference) or slightly loose fitting with a total clearance of about 0.5 to about 3 mils around the pin 228.

FIG. 29 is a semi-schematic partially cut-away side view of the valve assembly 254 of FIG. 28 in a second or use position, wherein the piston is in a more compressed state. The use position is moved by inserting the medical instrument tip 69 into the inlet nozzle 70 of the valve housing 184 and compressing the piston at the body section 154 (fig. 25), while forcing the bore 218 distally to follow the elongated actuation pin 228 and force the pin through the slit 160 to open the gap. Preferably, the upper top surface 162 of the piston is moved distally sufficiently to the enlarged lower section 82 of the valve housing 184 where sufficient circumferential space is provided to separate the two piston neck sections 157. At this point, fluid delivered from the medical implement through the valve 254 flows to the tip 69, through the gap 66 and out through the gap sides to the space between the piston outer surface and the inner wall surface of the valve housing 184, as previously described.

To facilitate the return of the piston 214 from the illustrated second position to the first position upon removal of the medical instrument from the inlet 72, the piston 214 itself is sufficiently resilient to return to the first position and/or a resilient member is used to bias the piston to the first position, as previously described. In this embodiment, friction between the actuating pin 228 and the wall surfaces of the two piston neck extensions 157 at the slit 160 should be kept to a minimum. In one exemplary embodiment, the residual fluid delivered to the valve acts as a lubricant to minimize friction. However, because the two piston neck extensions 157 deflect, a plurality of voids or uneven wall surfaces 256 are created adjacent the actuator pin 228 to reduce friction between the actuator pin and the wall surfaces of the two piston neck extensions 157.

Fig. 30 is a cross-sectional side view of yet another piston 258 in accordance with the present invention. In an exemplary embodiment, the piston 258 includes an upper flange 158, a neck section 156 having an upper neck section 34 and a lower neck section 30, a piston body 138 defining an interior cavity 142 with a flexible, resilient piston base 146, and a base flange 16. The piston 258 is configured for use with a valve housing (such as shown in fig. 8, 9 and 16) to function as a needleless injection inlet valve. Figure 30 is a cross-sectional side view of the piston of figure 32 taken along line 30-30.

Referring now to FIG. 32 in addition to FIG. 30, a piston 258 according to the present invention has an inverted Y-shaped slit 260 to provide a fluid passageway through the neck section 156 when used in conjunction with a valve housing. In one exemplary embodiment, the slot 260 includes an upper slot segment 262 and a lower slot segment 264, which in one embodiment includes two lower segments. In a preferred embodiment, the slit 260 is formed proximal to or above the lower neck section 30. As described below, when the slit 260 is open, a gap is provided for fluid flow through the upper neck section 34 of the piston.

Referring now to FIG. 31 in addition to FIG. 32, in one exemplary embodiment, the upper slit section 262 and the two lower slit sections 264 are formed by a cutting process after mold injection, the slits having a depth of about 15% to about 80% of the diameter of the neck section 156, with about 50% being preferred. The cutting method may be similar to that described above with reference to the pistons shown in fig. 13-16, except for a suitable Y-blade. In one exemplary embodiment, the upper slit section 262 is positioned vertically along the longitudinal axis of the piston and the two lower slit sections 264 are angled to the longitudinal axis of the piston. In an exemplary embodiment, the angle 266 of each lower slit section 264 is about 45 degrees from the longitudinal axis of the piston. The upper slit section 262 divides a portion of the neck section 156 into two piston neck sections 268, while the two lower slit sections 264 at an angle to the longitudinal axis divide the lower portion of the neck section 156 into the actuator 270.

Fig. 33 is a partial semi-schematic perspective view of the piston 258 shown in fig. 30-32.

Fig. 34 is a partial semi-schematic perspective view of the piston 258 shown in fig. 30-33. Fig. 34 shows piston 258 positioned within a valve housing, not shown, to form valve assembly 272. In fact, the valve housing, not shown, may be any of the valve housings described above. The piston 258 is shown in a first or ready position that blocks fluid flow between the valve housing inlet and outlet, as previously described. A partial cross-sectional perspective view of the tip 69 of the medical implement is shown at the piston top surface 162 just prior to opening the valve 272. The upper flange 158 compresses against the inner wall surface of the inlet nozzle to squeeze the two piston neck sections 268 together, compressing the slit 260 to form a fluid seal.

FIG. 35 is a semi-schematic perspective view of the valve of FIG. 34 with the tip 69 partially inserted into the inlet nozzle of the valve housing, not shown. FIG. 35 shows the position of the tip 69 inserted into the inlet nozzle and extended into the valve housing, wherein the slit 260 and the two piston neck sections 268 of the piston are moved generally to about the enlarged lower section 82 of the valve housing, not shown, as shown, for example, in FIG. 16. At this point, the two piston neck sections 268 push against the actuator sections 270 of the piston, which are separated by the angular alignment of the two lower slit sections 264, thereby opening the upper slit sections 262. The separation creates a gap 66 in the upper slit section 262 that creates a fluid path from the tip 69 through or toward the valve if a sample is taken through the valve 272. At the same time, the soft, resilient base 146 begins to bend and twist under the force of the tip 69.

FIG. 36 is a semi-schematic perspective view of the valve assembly 272 of FIG. 35 in a second position wherein the tip 69 of the medical implement is fully inserted into the inlet nozzle of the non-illustrated valve housing and prevented from further advancement by the relative geometry of the two. At this point, the gap 66 at the upper slit section 262 is further enlarged as the two upper neck sections 268 are further separated by the actuator section 270. The soft, resilient base 146 is further compressed and any wrinkles are more pronounced. Fluid flow from the medical implement can now flow through the gap 66 through the chamber 274 defined by the tip 69 and the flow space defined by the piston outer surface and the valve housing inner surface. The flow continues until it exits the outlet nozzle of the valve housing.

When the tip 69 is removed from the inlet nozzle of the unshown valve housing, the soft, resilient piston base 146 recoils and returns to its less compressed position to push the neck section 156 proximally toward the opening of the inlet nozzle. As the neck section 156 moves proximally, the two piston neck sections 268 push together due to the restriction or smaller inner circumference of the inlet nozzle near the valve housing opening, closing the gap 50 and terminating fluid communication between the inlet and outlet ports of the non-illustrated valve housing.

While only a limited number of embodiments of the needle-free inlet valve assembly and its components have been specifically described and illustrated herein, many modifications and variations will be apparent to those skilled in the art. For example, various valves may have luer slip interfaces instead of luer threads, the medical device may include a luer lock, the selected material may be opaque or translucent, different colors may be used, dimensions may be changed, and so forth. Moreover, it is to be understood and appreciated that features specifically discussed in one valve embodiment can be used in combination with another valve embodiment as long as the function is appropriate. For example, one valve may have a curvature and profile that may be incorporated into another valve for aesthetic purposes and to improve functionality (e.g., to improve clamping). It is therefore to be understood that valve assemblies and their components constructed in accordance with the principles of the present invention may be practiced otherwise than as specifically discussed herein. The invention is also defined in the following claims.

Claims (30)

1. A valve assembly, comprising:

a piston located inside the valve housing; the valve housing having an interior cavity, a bottom opening, and an inlet nozzle having an inlet and an interior wall surface; the piston comprises a flange, a neck section, a body section and a base; the piston further includes:

a slit comprising an upper slit section, a first lower slit section, and a second lower slit section, wherein the upper slit section divides the neck section into a first piston neck section and a second piston neck section, the first and second lower slit sections forming an angle with a longitudinal axis and dividing a lower portion of the neck section into an actuator configured to push against the first and second lower slit sections causing the upper slit section to open, the slit extending through at least part of the neck section below the flange such that a fluid flow path is formed between the slit and the inner wall surface of the valve housing; and

wherein the flange is in contact with the inner wall surface of the inlet nozzle to force at least a portion of the second piston neck section and the first piston neck section into contact with each other.

2. The valve assembly of claim 1, wherein the slit comprises a Y-shaped configuration.

3. The valve assembly of claim 1, wherein the slit is formed by a cutting method.

4. The valve assembly of claim 1 further comprising a luer nut attached to the bottom opening of the valve housing.

5. The valve assembly of claim 1, wherein the body segment includes an upper solid segment and a lower segment defining an internal cavity.

6. The valve assembly of claim 5, wherein the lower section flexes as the piston moves from the first position to the second position.

7. The valve assembly of claim 1, wherein the piston and the valve housing each include an antimicrobial composition.

8. The valve assembly of claim 1, further comprising a plurality of threads disposed at an inlet nozzle of the valve housing.

9. A valve assembly comprising a piston located inside a valve housing having an interior cavity, a bottom opening, and an inlet nozzle having an inlet and an interior wall surface; the piston includes a flange, a neck section below the flange, a body section, an outer wall surface, and a base; the piston further comprising a slit having an upper slit section with a first slit surface and a second slit surface extending in a direction from the inlet to the bottom opening, a first lower slit section and a second lower slit section, each slit surface comprising a tip of the flange formed continuously with an end of the other slit surface, wherein the slit is provided on an outer surface of the neck section; and an actuator formed below the upper slit section is configured to cause the first and second lower slit sections to separate and cause the first and second slit surfaces to separate.

10. The valve assembly of claim 9, wherein both ends of the continuously formed slit are formed under the flange.

11. The valve assembly of claim 9, wherein the first and second lower slit sections extend at an angle from the upper slit section to form a Y-shaped slit configuration.

12. The valve assembly of claim 9, further comprising a fitting attached to the valve housing.

13. The valve assembly of claim 9, wherein the slit is formed by a cutting method using an ultrasonic generator.

14. The valve assembly of claim 9, wherein the piston is made of a self-lubricating silicone material that flows liquid silicone against the outer wall surface of the piston.

15. The valve assembly of claim 14, wherein the piston is impregnated with an antimicrobial composition.

16. A valve assembly comprising a piston located inside a valve housing, the piston comprising a flange, a neck section, a body section comprising an upper section and a lower section defining an internal cavity, an outer wall surface and a base; the valve housing including an inlet nozzle having an inlet, a body section defining an interior cavity having an interior wall surface, and a bottom opening; a fluid space defined by a space between an outer wall surface of the piston and an inner wall surface of the valve housing for fluid to flow through the inlet nozzle and out the bottom opening; wherein the neck section of the piston includes a width and a slit formed through a portion of the width onto an outer wall surface of the piston for fluid flow,

the slit comprises an upper slit section, a first lower slit section, and a second lower slit section, wherein the upper slit section divides the neck section into a first piston neck section and a second piston neck section;

wherein the slit is only openable for fluid flow when wedged open by an actuator located below the upper slit section.

17. The valve assembly of claim 16, wherein the slit comprises a Y-shaped configuration.

18. The valve assembly of claim 16, wherein the slit is formed from the flange through a portion of the neck section below the flange across the width.

19. The valve assembly of claim 16, wherein the piston is made of self-lubricating silicone.

20. A method for manufacturing a valve assembly, the method comprising:

molding a piston comprising a flange, a body segment, a base, and a neck segment having a reduced diameter as compared to the body segment, the body segment defining an internal cavity;

cutting a slit in the neck section; said slit comprising an upper slit section dividing said neck section into a first piston neck section and a second piston neck section, a first lower slit section and a second lower slit section forming an angle with the longitudinal axis and dividing a lower portion of said neck section into an actuator, said slit extending through at least part of said neck section below said flange; and

placing the piston within a valve housing;

wherein a fluid flow path is formed between the slit and an inner wall surface of the valve housing;

wherein the cutting step comprises vibrating the blade with an ultrasonic generator.

21. The method of claim 20, wherein the blade moves toward the piston during the cutting step.

22. The method of claim 20, wherein the piston moves toward the blade during the cutting step.

23. The method of claim 20, wherein the slit comprises a Y-shaped configuration.

24. The method of claim 20, wherein the piston includes an antimicrobial composition.

25. A valve assembly comprising a valve housing, a piston located inside the valve housing, and a fitting secured to the valve housing; the outer surface of the piston and the inner surface of the valve housing define a fluid flow space when the piston moves from a first position to an axially compressed second position; a slit comprising an upper slit section, a first lower slit section, and a second lower slit section, the first lower slit section and the second lower slit section formed by a portion of the neck section of the piston and configured to separate under axial compression of the piston to form a gap, the gap in fluid communication with the fluid flow space; wherein at least one of the valve housing, the piston, and the fitting has an antimicrobial composition.

26. The valve assembly of claim 25, wherein the slit comprises a Y-shaped configuration.

27. The valve assembly of claim 25, wherein an antimicrobial composition is impregnated in at least one of the valve housing, the piston, and the fitting.

28. The valve assembly of claim 27, wherein the antimicrobial composition is impregnated in the valve housing, the piston, and the fitting.

29. The valve assembly of claim 25, wherein the antimicrobial composition includes at least one of silver and a silver compound.

30. The valve assembly of claim 29, wherein the silver compound comprises silver on zirconium phosphate.