Patent Description:
Patients are commonly injected with IV solutions that are initially provided in an IV reservoir fa bottle or bag) and dripped into the vein of the patient through an IV line. Typically, an injection port is provided along the IV line and adapted to function with a syringe to permit an injectate to be added to the IV solution. A check valve is also commonly included in the IV line to permit fluid flow only in the direction of the patient. This ensures that the injectate flows downstream toward the patient, not upstream toward the IV reservoir.

Document <CIT> discloses a drainage valve for use in pressure systems where pressure surges occur for draining an underground water system when the water pressure in the underground water system is off and for sealing the drainage valve against drainage when the water pressure is on. The drainage valve comprises a housing having a first annular support and sealing surface and a second annular support and a sealing surface for supporting a member that is nonextrudable through a drain passage in the drainage valve under normal operating pressures. <CIT> and <CIT> also disclose prior art check valves.

Conventional check valves utilize disc-shaped valve members that are generally flat and usually made of silicone which is naturally sticky. This geometry allows for the valve members to stick together (during bulk packing) thereby causing a condition known as "shingling" winch makes automated assembly of the conventional check valves difficult.

The present disclosure generally relates to check valves as set out in the appended set of claims. More particularly, the present disclosure relates to valve members of check valves having geometries capable of minimizing sticking together of the valve members during bulk packing or during assembly of the check valves.

In accordance with various embodiments of the present disclosure, a check valve includes an upper housing, a lower housing, a cavity interposed between and defined by the upper and lower housings, and a valve member mounted in the cavity to selectively permit fluid flow m a first direction, and prevent fluid backflow in a second direction opposite to the first direction. The upper housing defines an inlet of the check valve and the lower housing defines an outlet of the check valve. The cavity fluidly connects the inlet and the outlet. The valve member includes a valve body and a valve stem portion extending axially through a central axis of the valve body.

In accordance with various embodiments of the present disclosure, a check valve includes an upper housing defining an inlet of the check valve, a lower housing axially coupled to the upper housing and comprising an outlet of the check valve, and a cavity interposed between and defined by the upper and lower housings for fluidly connecting the inlet and the outlet. The check valve further includes a flexible valve member mounted in the cavity to selectively permit fluid flow in a first direction, and prevent fluid backflow in a second direction opposite to the first direction. The flexible valve member includes a body having a plurality of longitudinally extending feet disposed about an outer circumferential perimeter of the body.

In accordance with various embodiments of the present disclosure, a flexible valve member includes a valve body, and a plurality of feet disposed about and extending longitudinally from an outer circumferential perimeter of the valve body.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the subject technology as claimed. It is also to be understood that other aspects may be utilized, and changes may be made without departing from the scope of the subject technology.

The following figures are included to illustrate certain aspects of the embodiments, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.

The present description relates in general to check valves, and more particularly, for example and without limitation, to more particularly to valve members of check valves having geometries capable of minimizing sticking together of the valve members during bulk packing or during assembly of the check valves.

In accordance with some embodiments, the valve member may include a valve body and a valve stem portion extending axially through a central axis of the valve body. The valve members of the various embodiments described herein are advantageous in that the valve body and the valve stem portion may define a "jack" shape geometry that will reduce the exposed surface area available for sticking of the valve members during assembly. In particular, the presence of the valve stem portion limits the exposed surface area of the valve bodies available for sticking or "shingling. " In some embodiments, the exposed surface area of the valve members available for sticking is reduced by up to <NUM>%. The valve members can then be fed along an assembly line or track with reduced surface area for sticking and/or friction.

In accordance with some embodiments, the valve member either including or excluding the stem portion may additionally include plurality of feet at an outer circumferential perimeter of the valve body. The feet may each extend longitudinally from the outer circumferential perimeter of the valve body. The feet may be spaced apart from each other so as to form a castle-like shape around the perimeter of the valve body, and thus may be referred to as castellated feet. As depicted, the castellated feet may be oriented substantially perpendicularly with respect to the outer circumferential perimeter of the valve body. Benefits are realized in the geometry of the valve members with the castellated feet in that the castellated feet further prevent or obstruct contacting of the upper and/or lower surfaces of the valve bodies during bulk packing, assembly and/or transportation. In particular, since the upper surface of each of the castellated feet protrudes and is thus raised above the upper surface of the valve body, contacting and sticking together of the exposed surface areas of the upper surfaces of the valve body is limited. Similarly, since the lower surface of each of the castellated feet protrudes below the lower surface of the valve body, contacting and sticking together of the exposed surface areas of the lower surfaces of the valve body is limited. Additional benefits are realized in that due to the longitudinally protruding structure of the castellated feet, the valve member is capable of being maintained concentrically in a cavity of the check valve when the valve experiences a back pressure condition. Valves are symmetrical and can be assembled on either side.

<FIG> is a perspective view of a check valve <NUM>, in accordance with some embodiments of the present disclosure, not belonging to the claimed invention. <FIG> is a perspective view of a valve member <NUM> of the check valve of <FIG>, in accordance with some embodiments of the present disclosure. <FIG> illustrates an assembly line of the valve member <NUM> of the check valve <NUM> of <FIG> in accordance with some embodiments. As depicted, a top portion of the check valve <NUM> (i.e., an upper housing <NUM>) is displayed in cross-sectional view to more clearly illustrate some of the features of the check valve <NUM>. Referring to <FIG>, the check valve <NUM> includes an axially extending body <NUM> defining a central longitudinal axis X1. The body <NUM> may be a generally cylindrical (or tubular) structure and may include an upper housing <NUM> and a lower housing <NUM>. The upper housing <NUM> may include a first end portion <NUM> and an axially opposite second end portion <NUM>. As illustrated, a radial extent of the upper housing <NUM> at the second end portion <NUM> may be greater than the radial extent thereof at the first end portion <NUM>. The lower housing <NUM> may include an upstream internal surface <NUM>, and the second end portion <NUM> and the upstream internal surface <NUM> of the lower housing <NUM> may axially contact each other to co-operatively form a cavity <NUM> of the check valve <NUM>.

The upper housing <NUM> may include an inlet <NUM> of the check valve <NUM> at the first end <NUM>, and the lower housing <NUM> may include an outlet <NUM> of the check valve <NUM>. The body <NUM> may define an internal flow passage <NUM> axially extending between the inlet <NUM> and the outlet <NUM> and in fluid communication therewith. As is understood, the check valve <NUM> may permit fluid to flow from the inlet <NUM> to the outlet <NUM> (as indicated by arrow A), and minimize, or otherwise limit, fluid flow from the outlet <NUM> to the inlet <NUM> (as indicated by arrow B). As depicted, the upper housing <NUM> and the lower housing <NUM> may define the cavity <NUM> for fluidly connecting the inlet <NUM> and the outlet <NUM>. In the depicted embodiments the flexible valve member <NUM> may be mounted in the cavity <NUM> to selectively permit fluid flow in the first direction (indicated by arrow A), and prevent fluid backflow (reverse flow) in the second direction opposite to the first direction (indicated by arrow B).

In accordance with some embodiments, the valve member <NUM> may have a valve body <NUM> and a valve stem portion <NUM> extending axially through a central axis X2 of the valve body <NUM>. The valve body <NUM> may be in the form of a disc or any other circular plate. As depicted, the valve member <NUM> may be mounted on a support portion <NUM> of the lower housing <NUM>. In particular, the support portion <NUM> may include a central aperture <NUM> and a plurality of axially extending slots <NUM> through which fluid flowing from the inlet <NUM> and into the cavity <NUM> may enter the outlet <NUM> in an open state of the check valve <NUM>. As depicted, the valve stem portion <NUM> of the valve member <NUM> may be mounted in the central aperture <NUM> of the support portion. The aforementioned configuration of the valve member <NUM> may provide several manufacturing and assembly advantages. A common issue experienced during packaging, transportation and assembly of the check valve is that when conventional valve members (e.g., disc-type check valve members) are packaged in bulk and/or transported on a conveyance line, the valve members are prone to shingling. In particular, since conventional disc-type valve members are generally flat and made of silicone which is naturally sticky, this geometry allows for the conventional disc-type valve members to stick together (during bulk packing), thereby causing the "shingling". This makes automated assembly difficult. The valve member <NUM> of the various embodiments described herein is advantageous in that the valve body <NUM> and the valve stem portion <NUM> may define a "jack" shape geometry of the valve member <NUM> that will reduce the exposed surface area available for sticking of the valve members <NUM> during assembly. In particular, the presence of stem portion <NUM> limits the exposed surface area of the bodies <NUM> available for sticking or shingling. The probability for sticking of the valve members to occur is thus much lower since the stem portions will keep surfaces of the bodies apart at least in part. In some embodiments, the exposed surface area of the valve members <NUM> available for sticking is reduced by up to <NUM>%. As illustrated in <FIG>, the valve members <NUM> can now be fed along a track 70A with reduced surface area for sticking and/or friction. Additional benefits are realized in that since the valve members <NUM> will be concentrically disposed in the cavity <NUM> of the check valve <NUM>, peripheral circumferential edges of the valve member <NUM> are prevented from contacting an internal surface, e.g., a downstream internal surface <NUM> (described in further detail below) of the upper housing <NUM>, which could hold the valve open. Furthermore, because the valve member <NUM> is symmetrically shaped it can be assembled on either side thereof.

Referring back to <FIG>, the support portion <NUM> may be centrally disposed in the cavity <NUM>, and a central axis X3 of the support portion <NUM> may be coaxially aligned with the central longitudinal axis X1 of the body <NUM>. The support portion <NUM> may be coupled to, integrally formed with, or otherwise protrude from the upstream internal surface <NUM> of the lower housing <NUM>, and extend into the cavity <NUM>. As discussed in further detail below, the cavity <NUM> may form a part of the internal flow passage <NUM>, or may be otherwise fluidly communicated with the internal flow passage <NUM> and therefore, fluid flowing from the inlet <NUM> to the outlet <NUM> may flow via the cavity <NUM>.

<FIG> is a perspective view of a check valve <NUM>, in accordance with some embodiments of the present disclosure, not belonging to the claimed invention. <FIG> is a perspective view of a valve member <NUM> of the check valve <NUM> of <FIG>, in accordance with some embodiments of the present disclosure. <FIG> illustrates an assembly line of the valve member <NUM> of the check valve <NUM> of <FIG> in accordance with some embodiments. As depicted, a top portion of the check valve <NUM> (i.e., an upper housing <NUM>) is displayed in cross-sectional view to more clearly illustrate some of the features of the check valve <NUM>. Referring to <FIG>, similar to the embodiments of <FIG>, the check valve <NUM> includes an axially extending body <NUM> defining a central longitudinal axis X1. The body <NUM> may be a generally cylindrical (or tubular) structure and may include an upper housing <NUM> and a lower housing <NUM>. The upper housing <NUM> may include a first end portion <NUM> and an axially opposite second end portion <NUM>. As illustrated, a radial extent of the upper housing <NUM> at the second end portion <NUM> may be greater than the radial extent thereof at the first end portion <NUM>. The lower housing <NUM> may include an upstream internal surface <NUM>, and the second end portion <NUM> and the upstream internal surface <NUM> of the lower housing <NUM> may axially contact each other to co-operatively form a cavity <NUM> of the check valve <NUM>.

The upper housing <NUM> may include an inlet <NUM> of the check valve <NUM> at the first end <NUM>, and the lower housing <NUM> may include an outlet <NUM> of the check valve <NUM>. Similar to the embodiments of <FIG>, the body <NUM> may define an internal flow passage <NUM> axially extending between the inlet <NUM> and the outlet <NUM> and in fluid communication therewith. As is understood, the check valve <NUM> may permit fluid to flow from the inlet <NUM> to the outlet <NUM>, and minimize or otherwise limit, fluid flow from the outlet <NUM> to the inlet <NUM>. As depicted, the upper housing <NUM> and the lower housing <NUM> may define the cavity <NUM> for fluidly connecting the inlet <NUM> and the outlet <NUM>. In the depicted embodiments the flexible valve member <NUM> may be mounted in the cavity <NUM> to selectively permit fluid flow from the inlet <NUM> to the outlet <NUM>, and prevent fluid backflow (reverse flow) from the outlet <NUM> to the inlet <NUM>.

In accordance with some embodiments, similar to the valve member <NUM>, the valve member <NUM> may have a valve body <NUM> and a valve stem portion <NUM> extending axially through the central axis X2 of the valve body <NUM>. In the depicted embodiments, the valve member <NUM> additionally has a plurality of feet <NUM> disposed along an outer circumferential perimeter <NUM> of the valve body <NUM>. The feet <NUM> may each extend longitudinally from the outer circumferential perimeter <NUM> of the valve body <NUM>. As depicted, the feet <NUM> may be oriented substantially perpendicularly with respect to the outer circumferential perimeter <NUM> of the valve body <NUM>. In particular, the feet <NUM> may extend from and protrude substantially perpendicularly from an upper surface 22A and a lower surface 22B of the valve body <NUM>. As such, an upper surface 24A of each of the feet <NUM> may be positioned or protrude a predetermined height above the upper surface 22A of the valve body <NUM>. Similarly, a lower surface 24B of each of the feet <NUM> may be positioned or protrude a predetermined height below the lower surface 22B of the valve body <NUM>. In some embodiments, the feet <NUM> may be spaced apart from each other at regular intervals. For example, the valve member <NUM> may have two or more feet <NUM> equally spaced apart from each other. In other embodiments. However, the feet <NUM> may be spaced apart from each other at irregular intervals. For example, a spacing between each of the feet may vary according to the desired application. In some embodiments, adjacent pairs of the feet <NUM> define a recessed flow portion <NUM> therebetween, and through which fluid entering the cavity <NUM> from the upper housing may flow into the lower housing.

As depicted, the feet <NUM> may have a polygonal shape, for example a rectangular, square or any other suitable polygonal shape. In other embodiments, the feet <NUM> may have a curved shape, for example a circular, an oval or oblong shape. The configuration of the valve member <NUM><NUM> with adjacent feet <NUM> interposed by respective recessed flow portions <NUM> may yield a structure resembling that of a castle. Thus, the feet <NUM> may be referred to herein as castellated feet <NUM>. However, the various embodiments of the present disclosure are not limited the aforementioned configurations, and the shapes and spacing apart (i.e. the extent or size of the recessed flow portions <NUM>) of the feet <NUM> from each other may be varied as desired.

Similar to the embodiments of <FIG>, the valve member <NUM> may be mounted on a support portion <NUM> of the lower housing <NUM>. In particular, the support portion <NUM> may include a central aperture <NUM> and a plurality of axially extending slots <NUM> through which fluid flowing from the inlet <NUM> and into the cavity <NUM> may enter the outlet <NUM> in an open state of the check valve <NUM>. As depicted, the valve stem portion <NUM> of the valve member <NUM> may be mounted in the central aperture <NUM> of the support portion <NUM>. The aforementioned configuration of the valve member <NUM> may provide similar and additional manufacturing and assembly advantages as the valve member <NUM> of <FIG>. In particular, due to the valve member <NUM> also being configured with the valve stem portion <NUM>, the common issues described above which are experienced during packaging, assembly, and transportation are minimized. The "jack" shape geometry of the valve member <NUM> reduces the exposed surface area available for sticking of the valve members <NUM> during assembly, thereby reducing the possibility of occurrence of "shingling" or sticking together of the surfaces of the valve bodies <NUM> during transportation or assembly.

In some embodiments, the exposed surface area of the valve members <NUM> available for sticking is reduced by up to <NUM>%. As illustrated in <FIG>, the valve members <NUM> can now be fed along a track 70B with reduced surface area for sticking and/or friction. Benefits are realized in the geometry of the valve members <NUM> in that the castellated feet <NUM> further prevent or obstruct contacting of the upper and/or lower surfaces 22A, 22B of the valve bodies <NUM> during assembly and/or transportation. In particular, the configuration of the valve members <NUM> in which the upper surface 24A of each of the castellated feet <NUM> protrudes and is thus raised above the upper surface 22A of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22A from contacting and sticking to each other. Similarly, the configuration of the valve members <NUM><NUM> in which the lower surface 24B of each of the castellated feet <NUM> protrudes below the lower surface 22B of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22B from contacting and sticking to each other. Thus, the probability for sticking of the valve members <NUM> to occur is much lower than conventional valve members as the castellated feet <NUM> will keep surfaces of the bodies <NUM> apart at least in part. In some embodiments, the exposed surface area of the valve members <NUM> available for sticking is reduced by up to <NUM>%. As can be appreciated, the degree of reduction of the exposed surface area of the valve members <NUM> that is available for sticking may vary accordingly based on the size and geometry of the castellated feet <NUM>. Additional benefits are realized in that due to the longitudinally protruding structure of the castellated feet <NUM>, the valve member <NUM> is capable of being maintained concentrically in the cavity <NUM> of the check valve <NUM> when the valve member <NUM> experiences a back pressure condition. Furthermore, because the valve member <NUM> is symmetrically shaped it can be assembled on either side thereof. In all other respects, the valve member <NUM> may be identical to the valve member <NUM> described above with respect to <FIG>.

In accordance with some embodiments, the check valve <NUM> may further include a filter member <NUM> coupled, attached or otherwise bonded to an internal surface, e.g., surface <NUM> of the upper housing <NUM>. For example, the filter member <NUM> may be coupled, attached or otherwise bonded to a ledge <NUM> of the internal surface <NUM> through any appropriate methods including, but not limited to ultrasonic welding, heat sealing, insert molding, gluing or other attachment methods. The filter member <NUM> may be disposed upstream of, and spaced apart from the valve member <NUM>. As such, when the valve member <NUM> is subjected to an excessive reverse flow (flow from the outlet <NUM> to the inlet <NUM>) causing the valve member <NUM> to bow or deflect upwards, a gap remains between the filter member <NUM> and the valve member <NUM> to prevent the valve member <NUM> from stretching the filter member <NUM> past its elastic limit. Thus integrity of the filter member <NUM> is maintained even in the excessive backflow condition. The filter member <NUM> may be configured to restrict and minimize passage of undesirable matter in the fluid flowing through the check valve <NUM>.

The filter member <NUM> may be formed of a porous material capable of preventing particulate matter of a particular size from passing through and potentially reaching and causing failure of the valve member <NUM>. For example, the filter member <NUM> may be formed of a porous plastic material. Alternatively, the filter member <NUM> may be made of a non-woven cast material, a cork material, or any other porous fabric or material. The filter member <NUM> may be formed with a plurality of small holes or it may be woven, to provide pores of about <NUM> to <NUM> microns in size. In some embodiments, filter member <NUM> may be a flexible material such as a metal or polymeric material. In some embodiments, the filter member <NUM> may be formed of a material capable of withstanding or filtering flow rates of between <NUM> to <NUM> liters per hour. Additionally, the filter member <NUM> may be formed of a porous material capable of withstanding backpressures resulting from reverse flow of up to 200KPa. Advantageously, the latter configuration may minimize the possibility of the filter member <NUM> collapsing under the backpressure resulting from reverse fluid flow.

<FIG> is a perspective view of a check valve <NUM>, in accordance with some embodiments of the present disclosure. <FIG> is an exploded perspective view of the check valve <NUM> of <FIG>, in accordance with some embodiments of the present disclosure. <FIG> is an exploded cross-sectional view of the check <NUM> valve of <FIG>, in accordance with some embodiments of the present disclosure. <FIG> illustrates an assembly line of the valve member <NUM> of the check valve of <FIG> in accordance with some embodiments.

Referring to <FIG>, a top portion of the check valve <NUM> (i.e., an upper housing <NUM>) is displayed in cross-sectional view to more clearly illustrate some of the features of the check valve <NUM>. Referring to <FIG>, similar to the embodiments of <FIG> and <FIG>, the check valve <NUM> includes an axially extending body <NUM> defining a central longitudinal axis X1. The body <NUM> may be a generally cylindrical (or tubular) structure and may include an upper housing <NUM> and a lower housing <NUM>. The upper housing <NUM> may include a first end portion <NUM> and an axially opposite second end portion <NUM>. As illustrated, a radial extent of the upper housing <NUM> at the second end portion <NUM> may be greater than the radial extent thereof at the first end portion <NUM>. The lower housing <NUM> may include an upstream internal surface <NUM>, and the second end portion <NUM> and the upstream internal surface <NUM> of the lower housing <NUM> may axially contact each other to co-operatively form a cavity <NUM> of the check valve <NUM>.

In accordance with some embodiments, the valve member <NUM> may be similar in structure to the valve member <NUM>, with the exception that the valve member <NUM> excludes the valve stem portion <NUM>. Thus, similar to the valve member <NUM>, the valve member <NUM> may have a plurality of longitudinally extending feet <NUM> at an outer circumferential perimeter <NUM> of the valve body <NUM>. As described above, the feet <NUM> may be disposed around the outer circumferential perimeter <NUM> of the valve body <NUM> in manner resembling that of a castle, and therefore may be referred to herein as castellated feet <NUM>. The castellated feet <NUM> may each extend longitudinally from the outer circumferential perimeter <NUM> of the valve body <NUM>. Since the castellated feet <NUM> of the valve member <NUM> are identical to the castellated feet <NUM> of the valve member <NUM> and a detailed description of the castellated feet <NUM> was provided with respect to the valve member <NUM>, a detailed description thereof shall be omitted with respect to the valve member <NUM>.

In the depicted embodiments, the valve member <NUM> may be mounted on a support portion <NUM> of the lower housing <NUM>. The configuration of the valve member <NUM> with the plurality of castellated teeth <NUM> may provide similar manufacturing and assembly advantages as the valve member <NUM> of <FIG>. In particular, benefits are realized in the geometry of the valve members <NUM> in that the castellated feet <NUM> prevent or obstruct contacting of the upper and/or lower surfaces 22A, 22B of the valve bodies <NUM> during bulk packaging, assembly and/or transportation. For example, as illustrated in <FIG>, the valve members <NUM> can now be fed along a track 70C with reduced surface area for sticking and/or friction. In particular, as described above with respect to the valve member <NUM>, the configuration of the valve members <NUM> in which the upper surface 24A of each of the castellated feet <NUM> protrudes and is thus raised above the upper surface 22A of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22A from contacting and sticking to each other. Similarly, the configuration of the valve members <NUM> in which the lower surface 24B of each of the castellated feet <NUM> protrudes below the lower surface 22B of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22B from contacting and sticking to each other. Thus, the probability for sticking of the valve members <NUM> to occur is much lower than conventional valve members as the castellated feet will keep surfaces of the bodies <NUM> apart at least in part. In some embodiments, the exposed surface area of the valve members <NUM> available for sticking is reduced by up to <NUM>%. As can be appreciated, the degree of reduction of the exposed surface area of the valve members <NUM> that is available for sticking may vary accordingly based on the size and geometry of the castellated feet <NUM>.

Additional benefits are realized in that due to the longitudinally protruding structure of the castellated feet <NUM>, the valve member <NUM> is capable of being maintained concentrically in the cavity <NUM> of the check valve <NUM> when the valve member <NUM> experiences a back pressure condition. Furthermore, because the valve member <NUM> is symmetrically shaped it can be assembled on either side thereof. In all other respects, the valve member <NUM> may be identical to the valve member <NUM> described above with respect to <FIG>.

In accordance with some embodiments, the check valve <NUM> may further include a filter member <NUM> coupled, attached or otherwise bonded to an inner surface, e.g., surface <NUM> of the upper housing <NUM>. For example, the filter member <NUM> may be coupled, attached or otherwise bonded through any appropriate methods including, but not limited to ultrasonic welding, heat sealing, insert molding, gluing or other attachment methods. The filter member <NUM> may be disposed upstream of, and spaced apart from the valve member <NUM>. As depicted, the filter member <NUM> may be coupled or otherwise attached to a ledge <NUM> of an internal surface <NUM> of the upper housing <NUM>. The filter member <NUM> may be configured to restrict and minimize passage of undesirable matter in the fluid flowing through the check valve <NUM>.

The filter member <NUM> may be formed of a porous material capable of preventing particulate matter of a particular size from passing through and potentially reaching and causing failure of the valve member <NUM>. For example, the filter member <NUM> may be formed of a porous plastic material. Alternatively, the filter member <NUM> may be made of a non-woven cast material, a cork material, or any other porous fabric or material. The filter member <NUM> may be formed with a plurality of small holes or it may be woven, to provide pores of about <NUM> to <NUM> microns in size. In some embodiments, filter member <NUM> may be a flexible material such as a metal or polymeric material. In some embodiments, the filter member <NUM> may be formed of a material capable of withstanding or filtering flow rates of between <NUM> to <NUM> liters per hour. Additionally, the filter member <NUM> may be formed of a porous material capable of withstanding backpressures resulting from reverse flow of up to 200KPa. Advantageously, the latter configuration may minimize the possibility of the filter member <NUM> collapsing under the backpressure resulting from reverse fluid flow.

In accordance with some embodiments, the upper housing <NUM> may include at least one longitudinally extending rib <NUM> that protrudes radially inward from the upstream internal surface <NUM>. The at least one longitudinally extending rib <NUM> may be configured as a protruding surface which is disposed directly above or upstream of the filter member <NUM>. In some embodiments, the filter member <NUM> may be disposed between the plurality of longitudinally extending ribs <NUM> and the flexible valve member <NUM>. As depicted, the filter member <NUM> is positioned spaced apart from and disposed with a gap G between the filter member <NUM> and distal ends <NUM> of the plurality of ribs <NUM>. The aforementioned configuration is advantageous to maximize surface area for fluid flow from the inlet into the cavity and to minimize obstruction of fluid flow from the inlet <NUM> to the outlet <NUM>.

<FIG> are cross-sectional views of check valve <NUM>, in accordance with some embodiments of the present disclosure. <FIG> is a cross-sectional view of the check valve of <FIG> in the closed state, wherein the check valve restricts fluid flow in the reverse directions, in accordance with some embodiments of the present disclosure. As depicted, the upper housing <NUM> may include the internal surface <NUM> extending along the length of the interior of the upper housing <NUM> and defining the flow passage <NUM>. The internal surface <NUM> may include the upstream internal surface <NUM> and the downstream internal surface <NUM>. The cavity <NUM> may be at least partially defined by the downstream internal surface <NUM> of the upper housing <NUM>. In the depicted embodiments, the downstream internal surface <NUM> extends radially outward from the upstream internal surface <NUM>. The downstream internal surface <NUM> may include a projection <NUM> which extends circularly about the central longitudinal axis X1 of the body <NUM> and into the cavity <NUM>. In some embodiments, the projection <NUM> defines a sealing surface <NUM> at a distal end thereof. The projection <NUM> and therefore the sealing surface <NUM> may be disposed like a ring above the valve member <NUM>. As illustrated in <FIG> and <FIG>, in the normally-closed state of the check valve <NUM>, the valve member <NUM> contacts the sealing surface <NUM>. Because the valve member <NUM> contacts the sealing surface <NUM>, reverse flow (backflow) of fluid from the outlet <NUM> to the inlet <NUM> is prevented.

During operation, when a downstream pressure (i.e., a pressure applied by a fluid flowing from the outlet <NUM> to the inlet <NUM> is applied to the valve member <NUM>, the valve member <NUM> may deflect towards the sealing surface <NUM> to block the fluid communication between the inlet <NUM> and the cavity <NUM>, thereby restricting backflow of the fluid from the outlet <NUM> to the inlet <NUM>. Preventing backflow of the fluid is advantageous in that it restricts undesirable particulate matter, for example, contained in a drug dispensed from a secondary path from flowing back through the check valve <NUM>, thereby preventing the patient from receiving the proper drug dosage concentration or from timely delivery of the drug.

<FIG> is an enlarged partial cross-sectional view of the check valve of <FIG> in the closed state, wherein the check valve is subjected to an excessive backpressure, in accordance with some embodiments of the present disclosure. For example, an excessive back pressure exerted on the valve member <NUM> may cause the valve member to deflect or bend to such an extent that it abuts the filter member <NUM>, and exerts an upward force on the filter member <NUM>. When the valve member <NUM> is subjected to an excessive backpressure as illustrated in <FIG>, the plurality of longitudinally extending ribs <NUM> are advantageously configured to support the valve member <NUM> and limit the extent to which the valve member <NUM> stretches the filter member <NUM> when the valve member <NUM> is subjected to excessive back pressure. To this effect, the plurality of longitudinally extending ribs <NUM> prevent the valve member <NUM> from bowing to an extent where the valve member <NUM> overstretches and plastically deforms or otherwise damages the filter member <NUM>. The plurality of longitudinally extending ribs <NUM> thus act as a support member for the valve member <NUM> in the case of an excessive backflow so that it is not necessary for the filter member <NUM> to support the valve member <NUM> during excessive backflow. Thus, the plurality of longitudinally extending ribs also function advantageously to prevent the filter member <NUM> from being displaced upwards into the inlet <NUM> when excessive back pressures are experienced in the check valve <NUM>. Due to the presence of the longitudinally extending ribs <NUM>, the filter member <NUM> is prevented from being displaced upwards and into the inlet <NUM> as a result of the force exerted by the deflected valve member <NUM>.

<FIG> is a cross-sectional view of the check valve <NUM> of <FIG> in the open state when subjected to an upstream pressure, where the check valve <NUM> permits fluid flow in the forward direction, in accordance with some embodiments of the present disclosure. <FIG> is an enlarged partial cross-sectional view of the check valve <NUM> of <FIG> in the open state when subjected to an upstream pressure, where the check valve <NUM> permits fluid flow in the forward direction, in accordance with some embodiments of the present disclosure.

As depicted, during operation, fluid may enter the check valve <NUM> via the inlet <NUM>, and flow through the filter member <NUM> where it is filtered to trap the undesirable particulate matter, and into the cavity <NUM>. Any grit or other undesirable particulate matter larger in size than the pores of the filter member <NUM> may be trapped in the filter member <NUM>, and prevented from passing downstream to the valve member <NUM>. The upstream pressure (i.e., pressure applied by fluid flowing from the inlet <NUM> to the outlet <NUM>) applied to the valve member <NUM> causes the valve member <NUM> to bow or bend downwards at the outer edges thereof and deflect away from the sealing surface <NUM>. Thus, the check valve is shifted from the closed state to an open state where the inlet <NUM>, the cavity <NUM>, and the outlet <NUM> are fluidly communicated. In the open state, a gap may be created between the sealing surface <NUM> and the upper surface 22A of the valve member <NUM> to allow the filtered fluid to flow therethrough. The filtered fluid may then flow through the gap, into the cavity <NUM>, and exit the check valve <NUM> via the outlet <NUM> in the lower housing <NUM>.

The configuration in which the filter member <NUM> is positioned upstream of the valve member is advantageous in that it prevents passage of undesirable particulate matter to the valve member <NUM> which could otherwise cause damage or wear to the valve member. The aforementioned configuration also prevents the undesirable particulate matter from potentially becoming lodged between the valve member <NUM> and the sealing surface <NUM>, thereby preventing the valve member <NUM> from fully closing and sealing against reverse flow (backflow).

In contrast, in a conventional check valve configuration which does not include an integrated filter member, during low flow conditions, pressure exerted on the check valve as a result of the fluid flow may not be sufficient to fully open the check valve (e.g., to deflect the valve member <NUM>) such that grit (or other undesirable particulate matter) may pass through the gap. In such conditions, the grit may get lodged in the gap and the valve may not completely close. This undesirably causes the check valve to "weep," and allow fluid to flow through the valve in the reverse direction, thereby making the check valve ineffective.

<FIG> is a perspective view of a check valve <NUM>, in accordance with some embodiments of the present disclosure. As depicted, a top portion of the check valve <NUM> (i.e., an upper housing <NUM>) is displayed in cross-sectional view to more clearly illustrate some of the features of the check valve <NUM>. Similar to the check valve <NUM> of <FIG> and <FIG>, the check valve <NUM> includes an axially extending body <NUM> defining a central longitudinal axis X1. The body <NUM> may be a generally cylindrical (or tubular) structure and may include an upper housing <NUM> and a lower housing <NUM>. In accordance with some embodiments, the upper and lower housings <NUM> and <NUM> are similar in structure to the upper and lower housings <NUM> and <NUM> of the check valve <NUM>, thus a detailed description thereof shall be omitted with respect to the check valve <NUM>.

In accordance with some embodiments, the valve member <NUM> may be similar in structure to the valve member <NUM>, with the exception that the valve member <NUM> includes an additional friction rib <NUM> not present in valve member <NUM>. Thus, similar to the valve member <NUM>, the valve member <NUM> may have a plurality of longitudinally extending feet <NUM> at an outer circumferential perimeter <NUM> of the valve body <NUM>. As described above, the feet <NUM> may be disposed around the outer circumferential perimeter <NUM> of the valve body <NUM> in manner resembling that of a castle, and therefore may be referred to herein as castellated feet <NUM>. The castellated feet <NUM> may each extend longitudinally from the outer circumferential perimeter <NUM> of the valve body <NUM>. Since a detailed description of the castellated feet <NUM> was provided with respect to the valve member <NUM>, a detailed description thereof shall be omitted with respect to the valve member <NUM>.

In the depicted embodiments, the valve member <NUM> may be mounted on a support portion <NUM> of the lower housing <NUM>. The configuration of the valve member <NUM> with the plurality of castellated feet <NUM> may provide similar manufacturing and assembly advantages as the valve member <NUM> of <FIG>. In particular, as previously discussed with respect to valve members <NUM> and <NUM>, benefits are realized in the geometry of the valve members <NUM> in that the castellated feet <NUM> prevent or obstruct contacting of the upper and/or lower surfaces 22A, 22B of the valve bodies <NUM> during assembly and/or transportation. In particular, as described above with respect to the valve members <NUM> and <NUM>, the configuration of the valve members <NUM> in which the upper surface 24A of each of the castellated feet <NUM> protrudes and is thus raised above the upper surface 22A of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22A from contacting and sticking to each other. Similarly, the configuration of the valve members <NUM> in which the lower surface 24B of each of the castellated feet <NUM> protrudes below the lower surface 22B of the valve body <NUM> further limits the exposed surface area of the lower surfaces 22B from contacting and sticking to each other. Thus, the probability for sticking of the valve members <NUM> to occur is much lower than conventional valve members as the castellated feet <NUM> will keep surfaces of the bodies <NUM> apart at least in part. In some embodiments, the exposed surface area of the valve members <NUM> available for sticking is reduced by up to <NUM>%. As can be appreciated, the degree of reduction of the exposed surface area of the valve members <NUM> that is available for sticking may vary accordingly based on the size and geometry of the castellated feet <NUM>.

In accordance with some embodiments, the valve members <NUM>, <NUM>, <NUM>, and <NUM> may be formed of a flexible, resilient material which is fluid impervious. For example, the valve members <NUM>, <NUM>, <NUM>, and <NUM> may be made of a silicon material. In other embodiments, however, the valve members <NUM>, <NUM>, <NUM>, and <NUM> may be formed of any non-sticking, resilient material such as natural or synthetic rubber or plastic. The valve members <NUM>, <NUM>, <NUM>, and <NUM> may be formed of a material having a shore hardness of <NUM> or less.

In some embodiments, the valve members <NUM>, <NUM>, <NUM>, and <NUM> are not limited to any particular shape or size. In the depicted embodiments, however, the size of the valve members <NUM>, <NUM>, <NUM>, and <NUM> may be limited based on desired deflection/bending characteristics of the valve members valve members <NUM>, <NUM>, <NUM>, and <NUM> when subjected to either of the upstream or downstream forces. For example, the valve members <NUM>, <NUM>, <NUM>, and <NUM> may be sized and shaped so as to flex or bend under fluid pressure to permit forward flow (from the inlet <NUM> to the outlet <NUM>) of the fluid into the cavity <NUM>, and to limit fluid flow in the reverse direction.

In accordance with some embodiments, the check valve <NUM> may further include a filter member <NUM> coupled, attached or otherwise bonded to an inner surface, e.g., surface <NUM> of the upper housing <NUM>. Since a detailed description of the filter member <NUM>, how it functions, and how it may be coupled, attached or otherwise bonded to the upper housing <NUM> was provided with respect to the valve members <NUM>, a detailed description thereof shall be omitted with respect to the valve member <NUM>.

<FIG> is a perspective view of a valve member <NUM> of the check valve <NUM> of <FIG>, in accordance with some embodiments of the present disclosure. As depicted, at least one of the castellated feet <NUM> of the valve member <NUM> includes a curved friction rib <NUM> extending radially outward from an outer surface of the castellated foot <NUM>. The curved shape of the friction rib <NUM> may be advantageous over other rib shapes, for example a rib having a flatter or straighter shape because the curved shape or profile allows for reduced friction of the curved rib <NUM> with the downstream internal surface <NUM> as compared to a flat-shaped rib. The friction rib <NUM> may have a structure and/or be made of a may be formed of a flexible, resilient material which is capable of dampening or otherwise reducing a force, e.g., a friction force between the friction rib <NUM> and the downstream internal surface <NUM> of the upper housing <NUM>. For example, the friction rib <NUM> may be made of a silicon material. In other embodiments, however, the friction rib <NUM> may be formed of any non-sticking, resilient material such as natural or synthetic rubber or plastic. The aforementioned configuration of the valve member <NUM> with the friction ribs <NUM> is advantageous in that in the event that the valve member <NUM> becomes offset from its mounting position in the cavity <NUM> to the point where it contacts the downstream internal surface <NUM>, only the friction ribs <NUM> which protrude radially outward a greater extent than the castellated feet would contact downstream internal surface <NUM>. Thus, a surface area of the valve member <NUM> which contacts the downstream internal surface <NUM> is drastically reduced. Accordingly, a reduced surface area of the valve member <NUM> contacting the downstream internal surface <NUM> leads to reduced friction forces between the valve member and the upper housing as compared to a conventional valve member without the outward protruding friction ribs <NUM>.

<FIG> is a cross-sectional view of the check valve <NUM> of <FIG> in a closed state, wherein a central axis X4 of the valve member <NUM> of <FIG> is misaligned with a central axis X1 of the check valve <NUM>, in accordance with some embodiments of the present disclosure. <FIG> is a cross-sectional view of the valve member <NUM> of <FIG> misaligned with the central axis of the check valve <NUM>, in accordance with some embodiments of the present disclosure. <FIG> is a cross-sectional view of the check valve <NUM> of <FIG> in an open state, wherein the central axis X4 of the valve member <NUM> of <FIG> is misaligned with the central axis X1 of the check valve <NUM>, in accordance with some embodiments of the present disclosure.

As illustrated in <FIG>, in the normally-closed state of the check valve <NUM>, the valve member <NUM> contacts the sealing surface <NUM>. Because the valve member <NUM> contacts the sealing surface <NUM>, reverse flow (backflow) of fluid from the outlet <NUM> to the inlet <NUM> is prevented. During operation, when a downstream pressure (i.e., a pressure applied by a fluid flowing from the outlet <NUM> to the inlet <NUM>) is applied to the valve member <NUM>, the valve member <NUM> may deflect towards the sealing surface <NUM> to block the fluid communication between the inlet <NUM> and the cavity <NUM>, thereby restricting backflow of the fluid from the outlet <NUM> to the inlet <NUM>.

In some embodiments, the downstream pressure applied by the fluid flowing from the outlet <NUM> to the inlet <NUM> which places check valve <NUM> in the closed state may cause the valve member <NUM> to be displaced from its mounting position on the support portion <NUM>. In particular, a central axis X4 of the valve member <NUM> may be misaligned with the central longitudinal axis X1 of the check valve such that the valve member <NUM> contacts the downstream internal surface <NUM> of the upper housing <NUM>. The aforementioned configuration of the valve member <NUM> with the castellated feet <NUM> having the curved friction ribs <NUM> is advantageous in that since the friction ribs <NUM> protrude radially outward a greater extent than an outer surface of the castellated feet <NUM>, only the portion of the valve member <NUM> on which the friction ribs <NUM> are disposed contacts the downstream internal surface <NUM>. Thus, as illustrated in <FIG>, a surface area of the valve member <NUM> which contacts the downstream internal surface <NUM> is drastically reduced as compared to a conventional valve member configuration without the friction ribs <NUM>. The reduced surface area of the valve member <NUM> contacting the downstream internal surface <NUM> leads to reduced friction forces between the valve member <NUM> and the internal surface of the upper housing as compared to a conventional valve member which does not have the outward protruding friction ribs <NUM>. For example, in some embodiments, as illustrated in <FIG>, the surface area of the valve member <NUM> which contacts the downstream internal surface <NUM> is based on the number of friction ribs capable of contacting the downstream internal surface <NUM> at a time. As depicted, since a maximum of two of the friction ribs <NUM> contact the downstream internal surface <NUM> at a time, the surface area of the valve member <NUM> which contacts the downstream internal surface <NUM> is limited to the surface area of the maximum two friction ribs <NUM> which actually contact the downstream internal surface <NUM> at a given time.

As illustrated in <FIG>, in the open state of the check valve <NUM>, for example when subjected to an upstream pressure (i.e., a pressure applied by a fluid flowing from the inlet <NUM> to the outlet <NUM>), the check valve <NUM> permits fluid flow in the forward direction (direction of inlet port <NUM> to outlet port <NUM>). During operation, fluid may enter the check valve <NUM> via the inlet <NUM>, and flow through the filter member <NUM> where it is filtered to trap the undesirable particulate matter, and into the cavity <NUM>. Any grit or other undesirable particulate matter larger in size than the pores of the filter member <NUM> may be trapped in the filter member <NUM>, and prevented from passing downstream to the valve member <NUM>. The upstream pressure (i.e., pressure applied by fluid flowing from the inlet <NUM> to the outlet <NUM>) applied to the valve member <NUM> causes the valve member <NUM> to bow or bend downwards at the outer edges thereof and deflect away from the sealing surface <NUM>.

In some embodiments, the upstream pressure applied by the fluid flowing from the inlet <NUM> to the outlet which places check valve <NUM> in the open state may cause the valve member <NUM> to be displaced from its mounting position on the support portion <NUM>. In particular, a central axis X4 of the valve member <NUM> may be misaligned with the central longitudinal axis X1 of the check valve such that the valve member <NUM> contacts the downstream internal surface <NUM> of the upper housing <NUM> as discussed above. The aforementioned configuration of the valve member <NUM> with the castellated feet <NUM> having the curved friction ribs <NUM> is advantageous in that since the friction ribs <NUM> protrude radially outward a greater extent than an outer surface of the castellated feet <NUM>, when the check valve <NUM> is in the open state where fluid flows from the inlet <NUM> towards the outlet <NUM> and contacts the valve member <NUM>, the valve member <NUM> with the curved friction ribs <NUM> is displaced so as to follow a radial curved trajectory path away from the downstream internal surface <NUM> of the upper housing <NUM>. In this manner the curved friction ribs <NUM> further separate the valve member <NUM> from the downstream internal surface <NUM> of the upper housing <NUM>. Since contact between the valve member <NUM> and the downstream internal surface is minimized in this way, friction between the valve member <NUM> and the downstream internal surface <NUM> of the upper housing <NUM> is also minimized.

Claim 1:
A check valve, comprising:
an upper housing (<NUM>) defining an inlet (<NUM>) of the check valve;
a lower housing (<NUM>) axially coupled to the upper housing and comprising an outlet (<NUM>) of the check valve and a support portion (<NUM>);
a cavity (<NUM>) interposed between and defined by the upper and lower housings for fluidly connecting the inlet and the outlet; and
a flexible valve member (<NUM>, <NUM>) having a mounting position on the support portion (<NUM>) in the cavity and having an open state to selectively permit a fluid flow from the inlet (<NUM>) and into the cavity (<NUM>) to enter the outlet (<NUM>), and a closed state to prevent the fluid flow from the outlet (<NUM>) to the inlet (<NUM>), the flexible valve member comprising a body (<NUM>) having an outer circumferential perimeter (<NUM>) and a plurality of longitudinally extending feet (<NUM>) disposed about the outer circumferential perimeter of the body, wherein, a downstream pressure by the fluid flowing from the outlet (<NUM>) to the inlet (<NUM>) which places check valve in the closed state can displace the flexible valve member from its mounting position on the support portion (<NUM>) such that, in the open state and in the closed state, a central axis (X4) of the flexible valve member is misaligned with a central longitudinal axis (X1) of the check valve.