IT202300003804A1 - IMPROVED ONE-WAY VALVE DEVICE FOR INFUSION LINE OR FOR A MEDICAL PRODUCT AND ACTIVATABLE AT LOW PRESSURE OF THE FLUID CIRCULATING IN THAT LINE - Google Patents

Description

Description of an invention patent

DESCRIPTION

The subject of this invention is a one-way valve device or "check valve" for a medical infusion line or for a medical product according to the preamble of the main claim.

Valve devices of the type mentioned have long been used in medical products used within medical lines or in infusion and medical lines in which blood or a saline or physiological solution or another type of medical fluid flows to be infused into a patient usually intravenously.

These devices are essentially of two types: valve devices (or simply "valves") that must close in the case of retrograde flow in the line (i.e. the flow moves in the opposite direction to that required in the medical line) or valve devices that must open in the case of positive flow (i.e. in the desired direction within the medical line). The first valve devices are indicated as "normally open" type, the second valve devices are indicated as "normally closed" valve devices. These valve devices comprise a valve body with internal conduits associated with connectors for connection to a medical line. Between the internal conduits there is a unidirectional valve organ.

The present invention relates to a valve device or normally closed valve, i.e. having a valve member that usually closes the connection between the internal ducts of the valve body.

With reference to this last type of valve organ (?one-way valve? or ?check valve?), for their opening (or rather, that of the valve organ) it is required that the flow circulating in the medical line on which they are installed or in the products inserted in such lines has a pressure equal to or greater than a predetermined value indicated as ?opening pressure? (also called ?cracking pressure?). Usually one tries to keep this opening pressure value as low as possible, but this often leads to the creation of valve devices equipped with more delicate mechanisms than similar mechanisms of valve organs that open with higher opening pressure values; the use of such more delicate mechanisms, however, affects the ability of the valve device to stop retrograde flow at high pressures, higher than those to which valve devices with high opening pressures can withstand.

US2008/0169444 describes a valve device with a one-way valve for medical infusion lines that comprises a one-way valve defined by a diaphragm made of elastic material placed between a first and a second portion of a valve body provided with tubular connectors. This diaphragm is cup-shaped and has an external peripheral edge usually pushed into sealing contact against its own valve seat having a conical surface under an axial thrust exerted by the side wall of this cup-shaped diaphragm. This solution uses the pressure exerted by the retrograde flow in the medical line to exert a pushing force against the side wall of the cup-shaped diaphragm and which helps to maintain the seal against the valve seat.

US5992462 discloses a one-way valve device comprising a valve body having a base portion and a closure portion positioned in telescopic relation to each other and wherein an end chamber of the base portion is contained within a corresponding cup portion of the closure portion. A disc-shaped elastomeric valve member is positioned within the valve body and is defined by opposing flat surfaces. This valve member comprises a spherical portion positioned centrally thereon and which is captured between opposing valve supports supported by the closure portion and the base portion, respectively. These opposing valve supports seal against the inlet geometry of the valve body by deformation of the elastomeric valve member.

Another prior art, US2011/0108147 describes a valve device having a valve body comprising a first portion and a second portion provided with a connecting tube. Within the valve body and between said portions is placed a one-way valve provided with a disk-shaped diaphragm disposed within the valve body. Such disk-shaped diaphragm has an annular edge protruding from both sides of said diaphragm; such annular edge is adapted to be received in annular grooves of the opposite portions of the valve body. In this way the disk-shaped diaphragm is fixed to the valve body along its circumference. Such disk-shaped diaphragm has a plurality of radially formed openings and is disposed in a valve seat in the valve body so as to create a seal on a protrusion, present on the inlet side of a fluid in such body, through a non-perforated part of such disk-shaped diaphragm. During use, the incoming fluid initially passes through the disc openings and when the pressure of this fluid exceeds a predefined value, the aforementioned seal is broken.

The sealing of the disc on the valve body is due to radially symmetrical forces that urge the disc diaphragm to cooperate with the valve seat wall. In fact, the insertion of the protruding annular edge into the corresponding grooves generates a pre-tensioning of the disc diaphragm that brings it against the valve seat if it generates the seal on it.

The purpose of this invention is to provide a valve device equipped with a one-way valve or check valve for a medical infusion line or for products used in a medical line that is improved with respect to similar one-way valves already known.

In particular, the purpose of the invention is to provide a one-way valve device of the type indicated above in which the value of the fluid pressure capable of allowing the opening of the one-way valve organ is minimized, but in which there is still an effective blocking of the retrograde flow returning to the valve from the medical line.

Another aim of the present invention is to provide a one-way valve device of the type mentioned which has a limited number of components and which can be obtained in a timely manner and at a low cost.

These and other purposes which will be evident to the expert in the field are achieved by a unidirectional valve device according to the attached claims.

For a better understanding of this invention, the following drawings are attached for purely illustrative but not limiting purposes, in which:

Figure 1 is a perspective view of a one-way valve device according to the invention;

Figure 2 is an exploded side perspective view of the valve device of Figure 1;

Figure 3 is an exploded, other-side perspective view of the valve device of Figure 1;

Figure 4 is an exploded front view, with some parts shown in transparency, of the valve device of Figure 1;

Figure 5 is an enlarged perspective view of a component of the valve device of Figure 1 prior to assembly;

Figure 6 is a top view of the valve device of Figure 1;

Figure 7 is a sectional view along line 7-7 of Figure 6;

Figure 8 is a sectional view along line 8-8 of Figure 6;

Figure 9 is an enlarged view of the part indicated by A in Figure 7;

Figure 10 is an enlarged view of the part indicated by B in Figure 8;

Figure 11 is a perspective view from one side of a different embodiment of a one-way valve device according to the invention;

Figure 12 is an exploded view, from one side, of the device of Figure 11; and

Figure 13 is an exploded view, from one side, of the valve device of Figure 11.

With reference to figures 1-10, a valve device with a one-way valve (or check valve) is generically indicated with 1. The valve device 1 comprises a valve body 2 having a first portion 3 and a second portion 4 both having a tubular connector, respectively 5 and 6, known in itself suitable for connecting the valve body 2 to tubes of a medical line or to the body of a medical product inserted in such a line (such as a filter inserted in a medical infusion line), not shown. Around each connector 5 and 6, in the respective portion 3 or 4, a recess 7 is provided to facilitate such connection.

In Figures 1-4, arrows F and H indicate the direction of fluid flow into and out of valve body 2.

Inside the valve body 2 there is a valve component or organ 8; the valve organ is provided between internal ducts 10 and 11 respectively of the first portion (or inlet portion) 3 and of the second portion (or outlet portion) 4 connected to the tubular connectors 5 and 6; this valve organ 8 is made of elastomeric material and is designed to interrupt the connection between said internal ducts 10 and 11 when the pressure of a fluid present within the medical line at the inlet portion 3 is lower than a predefined value, for example 0.05 psi or 0.0034 bar. The valve organ 8 subjected to a different and higher pressure can deform elastically in such a way as to put said ducts 10 and 11 in communication and allow the passage of a medical fluid of a saline solution or blood through the valve body 2 and therefore between the two connectors; However, the valve organ 8 must also block the reverse flow of such fluid from the outlet portion towards the inlet portion by closing the connection between the aforementioned ducts 11. In this way, said valve organ operates as a one-way valve.

More specifically, each internal duct 10 and 11 of the valve body 2 opens at a surface, 3A and 4A respectively, of the inlet portions 3 and the outlet portion 4. These surfaces face each other and are in mutual contact. The surfaces 3A and 4A are made on raised parts 15 and 16 respectively of the inlet portion 3 and the outlet portion 4. These parts 15 and 16 are internal parts of these portions, with reference to their position in the valve body 2; the valve element 8 is placed between them. In the embodiment shown in figures 1-10, these parts 15, 16, coupled together, define a cavity annular or perimeter 19 suitable for receiving a thermoplastic material in an overmolding operation to which the portions 3 and 4 are subjected after their association (bringing the surfaces 3A and 4A into contact), and after the insertion of the valve element 8 between them. This overmolding constrains the portions 3 and 4 and defines the final conformation of the valve body 2.

Note that the duct 10 opens, at 10A, within a transverse recess 23 (i.e. placed with the longitudinal axis K orthogonal to the longitudinal axis W of the valve body 2, see figure 3) presenting a hollow central area 24, circular, from whose opposite sides extend substantially rectangular hollow lateral areas 25 directed towards the annular perimeter cavity 19. In correspondence with the central area 24, the duct 10 opens, at 10A. As can be seen for example in figures 7-10, this opening 10A of the duct 10 is substantially conical, widened towards the hollow central area 24 and is delimited, laterally within the hollow rectangular lateral areas, by protrusions 26 and 27, orthogonal to the axis K, therefore placed on the opposite sides of this opening 10.

Furthermore, the lateral zones 25, in addition to containing the aforementioned protrusions 26 and 27, have an increasing depth towards their end 25F located near the perimeter annular cavity 19, said ends 25F being delimited by a stepped extreme edge 28.

Similarly, the duct 11 opens at 11A into an oval or elliptical cavity 30 (with major axis parallel to axis K) formed in the outlet portion 4, a cavity which in turn opens into the surface 4A of this outlet portion. In the cavity 30 there are projections 31 facing the surface 4A whose function will be described later. The oval or elliptical cavity 30 is thus arranged orthogonally to that of the projections 26 and 27.

Furthermore, from the surface 4A, in correspondence with the hollow lateral areas 25 of the entrance portion 3 there are some projections 33 facing towards such hollow areas 25. The projections have a wedge shape, they lower towards the oval cavity 30 (from whose edge 30A or in proximity to whose edge 30A they depart) and they rise towards one of their ends 33B facing the perimeter annular cavity 19. Each of these ends 30B ends with a stepped extreme edge 38 in proximity to a corresponding recess 34 provided in the surface 4A which connects to the aforementioned cavity 19.

In the recess 23 and above the aforementioned projections 33 there is the valve organ 8 which substantially ?copies? the shape of the recess 23. Therefore the valve organ 8 has a central portion 35 with a rounded edge (and which we will define as ?circular?) and from which opposite arms 36 depart, ending with end flanges 37 protruding orthogonally from both sides 36A, 36B of each arm in correspondence with one of its free ends.

The valve organ, considered independently and when not inserted within the valve body 2, is substantially flat, that is, its central portion 35 and its arms 36 are in the same plane or, as in the embodiment of figures 11-13, the central portion 35 (flat) lies on a first plane while the arms lie on a different second plane placed very close to and parallel to the first plane.

More specifically, the central portion 35 of the valve organ 8 is designed to be positioned in correspondence with the hollow central area 24 of the transverse recess 23 of the first portion so as to rest with its opposing arms 36 on the projections 26 and 27 provided in this recess. The circular central portion 35 is positioned frontally to the projections 31.

The arms 36 of the valve organ 8 are positioned on the wedge-shaped projections 33 and have the end flanges 37 perpendicular to the arms 36 which abut against the above-mentioned stepped end edges 28 and 38, engaging them. Furthermore, the central portion 35 of the valve organ 8, when not subject to any fluid pressure present in the ducts 10 and 11, closes the connection between these ducts.

Additionally, due to the engagement between the flanges 37 and the stepped end edges 28 and 38, the valve member is maintained in tension along its arms 36 or along the K axis (arrow X in figure 5), a tension along the W axis of such valve organ is created by its cooperation with the projections 33, 26 and 27. Such tension obviously arises when the valve body 2 is assembled and subjected to overmoulding with thermoplastic material which forms a portion 40 within the annular cavity 19, material and operation which constrain the three parts of the valve device (the portions 3, 4 and the valve organ 8) in a safe and permanent manner, and which also create a total seal around the annular organ 8; such organ, however, is not affected by such overmoulding and can move freely within the body 2 so as to act as a one-way valve which opens only when the pressure of a medical fluid entering the valve body 2 from the conduit 10 exceeds a predetermined value.

The tension in the valve body is either perpendicular to the direction (permitted or positive) of flow (i.e. along the axis W of valve body 2) through said device, or axially aligned with the retrograde flow of such fluid or opposite to the direction indicated by the arrow H according to which the fluid returns to valve body 2 from the line through conduit 11.

When the pressure of the fluid entering from the conduit 10 exceeds a predetermined, but relatively low value, the parts of the circular edge of the central portion 35 of the valve member that are not directly parallel to the lines of force along the arms 36 (and also along the part of the central portion 35 in axis with such arms) may lift from the above-mentioned projections, allowing the creation of a minimum flow of fluid around the central portion 35 of the one-way valve member 8. There is therefore a positive flow of fluid between the conduit 10 and the conduit 11 (see figures 6-10).

As the fluid pressure increases, it is able to completely deflect the central portion 35 of the valve organ towards the oval cavity 30, thus allowing a greater flow of fluid between the ducts 10 and 11. This deflection is limited by the protrusions 31 present in the oval cavity 30.

This creates a two-stage one-way valve based on the pressure value of the circulating fluid. This double stage is also permitted by the shape of the recess 23 with variable depth towards the edges or towards the circumferential cavity 19 which allows the valve organ to deform, allowing for increased flow between the ducts 10 and 11.

The valve device obtained according to the invention allows to ensure a unidirectional flow of the fluid when this is necessary, between the conduit 10 of the inlet portion 3 and that 11 of the outlet portion 4. This valve device has a unidirectional valve member that can open even in low pressure conditions (for example equal to 0.05-0.07 psi or 0.0034-0.0048 bar), but which also ensures a greater flow following the overcoming of a tensile force inside the valve member 8, a force that arises thanks to the shape of this valve member 8 and the ways in which it is associated with the valve body 2.

At the same time, this valve organ 8 ensures that the communication between the aforementioned ducts 10 and 11 is completely closed with respect to a retrograde flow of fluid, that is, a flow that moves in a direction opposite to that required for medical use in the medical line to which the device 1 is associated.

The various components of the device 1 are obtained by molding, furthermore, according to the embodiment of figures 1-10, the assembly of such components is obtained by overmolding of thermoplastic material which defines the portion 40 of such valve device. Note that to facilitate the positioning of the coupled portions 3 and 4 (and between which the valve organ 8 is present) within the mold to perform said overmolding, the portions 3 and 4 have a faceted external conformation.

In figures 11-13 a different embodiment of the valve device 1 is shown. In these figures, parts corresponding to those already described are indicated with the same numerical references.

The main difference between the solution in figures 11-13 and that in figures 1-10 lies in the way the first portion 3 is connected to the second portion 4, a connection which is obtained by ultrasonic welding.

To this end, a first portion between the input portion 3 and the output portion 4 (in the figures, the portion 3) has a recess 80 around the internal part 15 delimited externally by a peripheral edge 81 of the aforementioned portion. The second portion (in the figures, the portion 4), instead, has a wall 82 rising around the internal part 16, said wall 82 being suitable to be introduced into the aforementioned recess 80.

In the assembly, after the aforementioned coupling between the wall 82 and the recess 80, the portions 3 and 4 are ultrasonically welded in correspondence with said wall 82 and recess, constraining said portions 3 and 4 in a definitive manner.

Preferred embodiments of the invention have been described; others may still be realized, such as the one in which the characteristics of the portions 3 and 4 previously described are exchanged between the portions themselves. This embodiment is also the object of the invention, the characteristics of which are however defined by the claims that follow.

Claims (15)

1. Unidirectional valve device for a medical line or for a medical product suitable for being placed in such medical line, said valve device (1) being suitable for allowing a flow of fluid only in one direction within such line or medical product, but intercepting said flow in the opposite direction, the valve device (1) comprising a valve body (2) having an inlet portion (3) and an outlet portion (4), each of such portions (3, 4) comprising a connector organ (5, 6) for connection to the medical line or to the medical product, said connector organs (5, 6) being connected to ducts (10, 11) internal to said valve body (2), between said internal ducts (10, 11) being provided a unidirectional valve organ (8) arranged within a respective seat (23) internal to said valve body (3), said valve organ (8) being made of elastomeric material and being characterised in that said valve organ comprises an enlarged central area (35) from which symmetrically extend opposite arms (36), said arms being elongated along a common longitudinal axis (K), the enlarged central area (35) of said valve organ having rounded edges connecting said elongated arms, said enlarged central area (35) being provided between said internal ducts (10, 11) of said valve body (2) so as to intercept or allow the connection between said internal ducts (10, 11), the valve seat (23) having a shape corresponding to that of the valve organ (8) which is retained within said seat and maintained therein in a tensile stressed configuration. 2. Valve device as claimed in claim 1, characterised in that the enlarged central area (35) of the valve organ (8) has a circular shape, the elongated arms (36) protruding symmetrically from said central area (35). 3. Valve device as claimed in claim 1, characterised in that said valve member (8) is flat. 4. Valve device as per claim 1, characterised in that said elongated opposing arms (36) have opposing sides (36A, 36B) and terminate at one of their free ends with opposing end flanges (37) protruding orthogonally from said opposing sides (36A, 36B). 5. Valve device as claimed in claim 4, characterised in that said flanges cooperate with extreme steps (28, 38) of the valve seats (23). 6. Valve device according to claims 1 and 4, characterised in that said valve seat (23) comprises a transverse recess made within an internal part (15) of at least one of the first between the inlet portion (3) and the outlet portion (4) of the valve body (2), in said recess opening a corresponding internal duct (10, 11) of said valve body (2), said valve seat (23) having a hollow central area (24) in which said internal duct (10, 11) opens, suitable for containing the enlarged central area (35) of the valve organ (8) and hollow elongated areas (25) positioned laterally to said hollow central area (24) suitable for containing said opposing elongated arms (36) of said valve organ (8), said hollow elongated areas (25) ending with an extreme edge (28), stepped, with which the extreme flanges (34) of the valve organ cooperate by engagement. the aforementioned elongated opposing arms (36). 7. Valve device as per claim 6, characterised in that protrusions (26, 27) are provided within said valve seat (23) positioned on the opposite sides of the hollow central area (24). 8. Valve device as claimed in claim 7, characterised in that said protrusions (26, 27) are positioned orthogonally to the longitudinal axis (K) of the valve organ on which the opposing elongated arms (36) of the latter lie. 9. Valve device as per claim 6, characterised in that an oval or elliptical cavity (30) is provided within an internal part (16) of the second portion between the inlet portion (3) and the outlet portion (4) of the valve body, said oval or elliptical cavity (30) opposing the hollow central area (24) of the transverse recess (23) formed within the first portion, between said inlet and outlet portions (3, 4) and laterally to said oval or elliptical cavity, projections (33) being provided facing the hollow elongated areas (25) of said transverse recess (23), said projections having a wedge shape and lowering at one end towards the oval or elliptical cavity, the other end forming a step (38) with said internal part (16) with which a corresponding end flange (34) of one of the opposing elongated arms (36) of the valve organ cooperates. 10. Device as per claim 6, characterised in that said hollow elongated zones (25) have increasing depth moving away from the central zone (24). 11. Device according to claims 6 and 9, characterised in that said internal parts (15, 16) of said inlet (3) and outlet (4) portions are raised on the respective portions, the coupling of said inlet and outlet portions (3, 4) causing said internal areas to define a perimeter annular cavity (19) on the valve body (2). 12. Device as per claim 11, characterised in that said peripheral annular cavity contains a portion (40) in thermoplastic material overmoulded on said entry and exit portions (3, 4). 13. Device as claimed in claim 1, characterised in that said input and output portions (3, 4) are ultrasonically welded. 14. Device as per claim 13, characterised in that a first portion between the input portion (3) and the output portion (4) has an internal recess (80) suitable for accommodating an internal wall (82) of the second portion between the other of the input portion (3) and the output portion (4), said internal wall (82) being ultrasonically welded in the internal recess (80). 15. Device according to claims 6, 9 and 14, characterised in that said internal wall (82) is made around the internal part (16) of the second portion between one of the input portion (3) and the output portion (4), the internal recess (80) being provided between the internal part (15) of the first portion between the other of the input portion (3) and the output portion (4) and a peripheral edge (81) of said first portion.