WO1989002764A1

WO1989002764A1 - Nonreturn valve arrrangement

Info

Publication number: WO1989002764A1
Application number: PCT/AT1988/000077
Authority: WO
Inventors: Günter HEIMHILCHER
Original assignee: Heimhilcher Guenter
Priority date: 1987-10-05
Filing date: 1988-10-05
Publication date: 1989-04-06
Also published as: AU2522388A

Abstract

A nonreturn valve arrangement for a device for suction of body liquids comprises a two-part housing (1), and an intermediate plate (15) and a membrane (16) inserted internally in a sealed manner between the parts (4, 6) of the housing. The membrane (16) has valve flap sections and, together with bores (10, 20, 24, 25) in the housing parts (4, 6) and in the intermediate plate (15), forms, on the one hand, a nonreturn valve (26) between the intake connecting piece (2) and a pump connecting piece (5) and, on the other hand, a nonreturn valve (27) between the pump connecting piece (5) and a lateral outlet (3). The nonreturn valves are preloaded in the closing position by the elasticity of the membrane. When the liquid is sucked through the intake connecting piece (2) to the pump connecting piece (5), the nonreturn valve (26) between the intake connecting piece (2) and the pump connecting piece (5) opens, whereas when the body liquid is pumped from the pump connecting piece (5) to the outlet (3), the nonreturn valve (27) between the pump connecting piece (5) and the lateral outlet (3) opens.

Description

Non-return valve arrangement

Field of the Invention

The invention relates to a non-return valve arrangement for a device for suctioning and pumping liquids or gases, with a housing which has a suction connection part, an opposite pump connection part and a lateral outlet and in which check valves on the one hand between the suction connection part and the pump connection part and on the other hand * are provided between the pump connection part and the lateral outlet, the shut-off valve between the suction connection part and the pump connection part being open during suction and the shut-off valve between the pump connection part and the lateral outlet being closed, whereas, during pumping, the shut-off valve between the suction connection part and the pump connection part is closed and the shut-off valve between the pump connector and the side outlet is open.

Such a valve arrangement is preferably used in medicine in a device for suctioning off body fluids.

State of the art

A non-return valve arrangement of the type mentioned at the outset. Connection with a cannula, an injection syringe as a pump and a receptacle is disclosed in DE-A-26 28 369. The known valve arrangement has a housing body in which two check valves with balls are provided as valve bodies, which are assigned conical constrictions in the bores of the housing body as a valve seat. In order to secure the valve balls in the bores, separate retaining rings are also used as valve catchers, which allow bodily fluids to flow through when the valve ball is lifted off the valve seat. In addition, a separate injection inlet is provided in the known valve arrangement in order to be able to inject a medicament if necessary.

A disadvantage of the known valve arrangement is that the check valves have no defined closed position in the pressure-neutral situation, and that the valves can therefore, depending on the position which the valve arrangement occupies in the room, be open. However, this means that, for example, when pumping body fluid previously drawn through the cannula into the hypodermic syringe to the outlet (and from there into the bag-shaped receptacle), some body fluid or air can get back to the suction side and to the cannula pierced into a body part of a patient. This poses a risk to the patient, and there is in particular the risk of an embolism.

Another disadvantage is that the valve arrangement is only suitable for low-viscosity, well-flowing liquids, but hardly for higher-viscosity liquids, especially also those that contain solid particles, since the space for the flow in the area of the check valves is too narrow for this.

Finally, it is also a particular disadvantage that the known valve arrangement is relatively complicated and expensive to manufacture and to assemble, which is why the known valve arrangement is also not suitable as a so-called disposable part for single use. This was obviously the reason why. the known valve arrangement, as far as known to the applicant, has not become established in practice. Instead, nowadays one-way valve units are commonly used in connection with devices for suctioning body fluids, in which a three-way valve is installed, which has to be switched manually from the one position in which body fluid can be drawn into the syringe barrel into the other position the previously drawn body fluid is pumped out of the syringe barrel into a receptacle or bag. This manual operation of the three-way valve in addition to actuating the injection syringe provided as a pump therefore requires in in practice two people, ie usually a doctor operates the injection syringe used as a pump and a nurse operates the three-way valve. Nevertheless, incorrect operation can occur, so that a risk to the patient cannot be ruled out here either.

Disclosure of the invention

It is an object of the invention to provide a non-return valve arrangement of the type specified in the opening paragraph which is simple and inexpensive to manufacture, i.e. Manufacture and assembly allowed, so that it can be designed as a disposable part, and which nevertheless ensures a safe function regardless of the position in the room; Furthermore, it should also be suitable for use in the presence of highly viscous liquids, and the sucked or pumped liquids can also contain solid particles.

For this purpose, the non-return valve arrangement according to the invention of the type specified at the outset is characterized in that the two shut-off valves are formed by a common elastic membrane which has two elastically deformable valve flap sections which are defined by slot openings and which have corresponding, axially aligned bores in the interior of the housing cooperate, with each pair of holes, the hole located on the side of the respective check valve to which the liquid or gas is to have a larger cross section than the opposite hole, the cross section of which is smaller than the size of the associated valve flap section, and the edge of which forms the valve seat for the valve flap section.

With such a training, the above objective is advantageously met. The provision of a common elastic membrane to form both check valves not only brings advantages in terms of production technology, but also a reliable, 'position-independent function of the check valves. or check valves. The membrane, that is, its valve flap sections, is biased by the inherent elasticity into the respective closed position, so that both valves are closed in the pressure-neutral state, regardless of the position of the valve arrangement in space, since the gravity acting on the valve flap sections is in any case less than the valve closing force caused by the inherent elasticity of the membrane. On the other hand, since the ^" valve flap sections can be deformed sufficiently far into the respective larger bore, ^" a correspondingly large flow cross-section can be obtained when the valve is open, and accordingly the present valve arrangement is also suitable for working with higher-viscosity liquids or with liquids that are solid particles included, suitable.

The valve arrangement according to the invention can also be provided as a one-way valve unit due to the simple manufacture and assembly, and in order to achieve a particularly simple construction for this purpose, it is particularly advantageous according to the invention if the housing consists of two housing parts firmly connected to one another, between which one is inside with an intermediate plate provided with a cross-sectional bore and a smaller cross-bore for the two shut-off valves, on which the diaphragm rests, the one, first housing part containing the intake connection part, with the associated cross-sectional bore for the one shut-off valve, and the outlet, with associated cross-sectional bore for the other shut-off valve, while the other, second housing part has the pump connection part and a connecting channel for flow connection of the two bores in the intermediate plate to the pump connection part.

To connect a cannula to the suction connection part, it is furthermore favorable if the smaller cross-sectional bore in one of the first housing parts connects directly to a cone bore of the suction connection part provided with a Luer lock connection. Such a Luer lock connection is known per se, cf. for example also the DIN standard DIN 13090.

Correspondingly, for connecting an injection syringe as a pump to the pump connection part, it can preferably be provided that the pump connection part of the other, second housing part opposite the suction connection part is likewise provided with a Luer lock connection with a conical bore which opens into the connecting channel.

For assembly, it is also advantageous if the elongate intermediate plate has an eccentric projection on one long side, which fits into a corresponding groove in the first housing part in order to ensure that the intermediate plate is inserted in the correct direction.

The two housing parts are preferably connected to one another by gluing or by welding.

An ABS (acrylonitrile-butadiene-styrene copolymer) plastic is a material which is particularly suitable for the housing parts and also for the intermediate plate with regard to the design of the valve arrangement as a one-way valve unit. The membrane, however, can consist of silicone rubber.

Finally, in order to ensure a particularly reliable function even with possibly less elastic membranes, it is also advantageous if the edge of each bore with a smaller cross section is provided with a burr-shaped ring elevation in order to additionally pretension the valve flap sections into the closed position.

Brief description of the drawing

The invention is explained in more detail below with the aid of a particularly preferred exemplary embodiment, to which it should not be restricted, however, with reference to the drawing. In this show:

1 shows a longitudinal section through a non-return valve arrangement.

FIG. 2 shows a top view of this valve arrangement according to FIG. 1; 3 shows a longitudinal section through the upper, first housing part of the valve arrangement in FIG. 1 to illustrate a groove for securing the position of an intermediate plate;

4 shows a bottom view of the upper housing part according to FIG. 3;

5 shows a plan view of the intermediate plate inserted in the housing of the valve arrangement, a lateral projection for securing the position being illustrated;

6 shows a plan view of the unitary membrane provided as a valve sealing member;

7 shows a plan view of the lower housing part as shown in FIG. 1, to illustrate the connecting channel provided therein;

FIG. 8 is a top view similar to FIG. 5, showing an intermediate plate that has been modified somewhat; and

Fig. 9 shows a longitudinal section through this modified intermediate plate and the adjacent area of the upper housing part, with the intermediate layer of the membrane.

Description of the preferred embodiment

The backflow blocking valve arrangement shown in the drawing is intended for use in a device for suctioning body fluids and the like, and it has a two-part housing 1 with a suction connection part 2 and an outlet 3 on a first housing part 4 and a pump connection part 5 on one another, second housing part 6. Here, as is known per se from DE-A-26 28 369, a cannula (not shown in the drawing) can be connected to the suction connection part 2 in order to draw in body fluid in the direction of the arrow 8, for which purpose a Luer lock connection 7 ( according to DIN 13090) is provided. The suction connection part 2 is provided in its interior with a slightly conical bore (luer cone) 9 which merges into a bore 10, possibly via a step 11 (FIG. 3).

In a similar manner, the pump connection part 5 forms a Luer lock connection 12 (according to DIN 13090) for one in the drawing Injection syringe, also not shown in more detail (see, for example, DE-A-26 28 369), with which the body fluid can be drawn in in the direction of arrow 8, the body fluid entering the interior of the syringe barrel (see also the right part of the double arrow 13 in Fig. 1).

3 and 4, a receiving chamber 14 is then provided in the upper, first housing part 4 for receiving an intermediate plate 15, with the interposition of a membrane 16, and a circumferential, self-contained, upwardly projecting edge part 17 of the lower, second housing part 6. The wall 18 of this receiving chamber 14, as can be seen from FIG. 1, is flush on the outside with a laterally projecting fastening flange 19 of the lower, second housing part 6, and the two housing parts 4, 6 are in the assembled state according to FIG. 1 along the wall 18 on the one hand or the flange 19 and the projecting part 17 on the other hand firmly connected; this connection can be accomplished by welding or gluing.

The already mentioned bore 10 on the suction side opens into the chamber 14 in its bottom plane, and likewise in this plane a cross-sectionally larger bore 20 opens into the chamber 14 on the outlet side or pressure side, with this bore 20 the already mentioned outlet 3 communicates. The outlet 3 itself can be designed, for example, as an insertion cone with annular ribs for insertion into a hose end or the like, in order to connect the outlet 3 to a bag-like receptacle, for example (which is also not shown in the drawing, but the DE-A- 26 28 369). The outlet 3 can also be a Luer hole connection.

3 and 4 then a lateral groove 21 extending over the height of the wall 18 of the receiving chamber 14 can be seen, in which groove a nose-shaped projection 23 provided eccentrically on the longitudinal edge 22 of the intermediate plate 15 (see FIG. 5) fits. In this way, a right-sided ^' insertion of the intermediate plate 15 in the Receiving chamber 14 of the upper, first housing part 4 is ensured during assembly, which is important because holes 24 (cross-sectionally larger hole) and 25 (smaller-section hole) provided in the intermediate plate 15 are correctly assigned to the holes 10 and 20 in the first housing part 4 must be, cf. 1. The cross-sectional representation of FIG. 1. Thereby, a bore 10 or 25 (on the inflow side) with a smaller cross section is axially opposite a bore 24 or 20 (on the outflow side) with a larger cross section, and between these bores 10, 24 and 25, which are opposite one another , 20, the membrane 16 already mentioned is arranged to form two check valves, namely check valves 26 (between suction connection part 2 and pump connection part 5) and 27 (between pump connection part 5 and outlet 3).

To form these two check valves 26, 27, the membrane 16, the outline of which is essentially the same as that of the intermediate plate 15 or the receiving chamber 14 (apart from the projection 23 or the groove 21), has two valve flap sections 28, 29 (FIG. 6) by eg Circular arc-shaped slots 30, 31 and 32, 33 are laterally limited, where they can deform due to the pressure difference while overcoming resistance to the larger cross-section bore 24 or 20 when the pressure there is lower than on the opposite side, where the respective smaller cross-sectional bore 10 or 25 is located. If there is a reverse pressure drop or pressure equality in the associated bores 10, 24 or 25, 20, the respective valve 26 or 27 remains closed.

In the lower, second housing part 6, a connecting channel 34 is provided within the upwardly projecting part 17, which connects the smaller bore 25 in the intermediate plate 15 with the conical bore 35 (luer cone) in the pump connection part 5 or the latter with the larger bore 24 in the intermediate plate 15 connects.

In this way, with the two check valves 26, 27, which are formed by the valve flap sections 28, 29 of the diaphragm 16, the edges acting as a valve seat of the smaller cross-sectional bores 10 and 25 are present, a valve system is obtained in which, when body fluid is sucked in, the check valve 26 opens due to the resulting negative pressure in the bore 24 and the check valve 27 is closed, so that the body fluid through the bores 9, 24 and 35 can get from the cannula into the syringe barrel; In the subsequent step, in which the body fluid is to be pumped out of the syringe barrel, for example, into a bag-shaped receptacle on the outlet side, and in which the plunger of the syringe is moved back again to the starting position, the check valve 26 closes (ie more precisely it remains closed), whereas the check valve 27 opens due to the increasing pressure in the bore 25, so that the previously aspirated body fluid now from the syringe, via the pump connection part 5, through the connecting channel 34, the bore 25, the bore 20 and through the outlet 3 into the receptacle can reach.

The housing parts 4, 6 and the intermediate plate 15 are preferably made of ABS plastic, while a silicone rubber is used for the membrane 16.

It is advantageous in the valve arrangement described with the elastic membrane 16 as the valve element that, in the pressure-neutral state, the check valves 26, 27 are reliably closed due to the internal stress of the elastic membrane 16, regardless of the respective position of the valve arrangement, which is therefore compared to Representation in the drawing can also be rotated, for example, by 180 ° or can otherwise assume any position in space. The valve arrangement described is also well suited for suctioning and pumping away higher-viscosity liquids, these liquids possibly also containing solid particles, the passage of which through the diaphragm check valves is easily guaranteed. Furthermore, the valve arrangement described with the mere two housing parts 4, 6, the intermediate plate 15 and the membrane 16 is also simple to manufacture and unproblematic to assemble, which also includes the groove 21 in the first housing part 4 engaging nose projection 23 of the intermediate plate 15 contributes. In this case, a correct assembly of the individual parts is ensured in any case, the alignment of the membrane 16 not being important, since this is symmetrical. Finally, the valve arrangement can also be sterilized without problems.

For an even more secure elastic prestressing of the membrane 16, i.e. of its valve flap sections 28, 29, in the closed position, a burr-shaped ring elevation 36 can be provided on the respective valve seat, i.e. on the edge of the respective smaller cross-sectional bore 10 or 25, as shown in FIGS. 8 and 9 for the bore 25 of the intermediate plate 15 and in FIG. 9 is also illustrated for the bore 10 of the first housing part 4, it also being shown how the membrane 16 bulges in the area of the respectively opposite cross-sectional bore 20 or 24 for the purpose of pretensioning.

Otherwise, the intermediate plate 15, the diaphragm 16 and the housing parts in the embodiment according to FIGS. 8 and 9 correspond entirely to the embodiment explained above with reference to FIGS. 1 to 7, so that a new description is not necessary.

Industrial applicability

The present valve arrangement can above all be used as a so-called one-way valve unit in connection with devices with which a flowable medium is first to be sucked in and then pumped into a receptacle, whereby the valve unit should function automatically. In particular, the valve arrangement can be used in a device for aspirating body fluids, for puncturing and the like.

Claims

Claims:

1. non-return valve arrangement for a device for suction and pumping of liquids or gases, with a housing (1) having an intake connector (2), an opposite pump connector (5) and a side outlet (3) and in the check valves (26; 27) are provided on the one hand between the suction connection part (2) and the pump connection part (5) and on the other hand between the pump connection part (5) and the lateral outlet (3), the shut-off valve (26) between the suction connection part (2) during suction. and the pump connection part (5) is open and the check valve (27) between the pump connection part (5) and the lateral outlet (3) is closed, whereas during the pumping the check valve (26) between the suction connection part (2) and the pump connection part (5) is closed and the check valve (27) between the pump connection part (5) and the lateral outlet (3) is open, characterized in that the two check valves (26; 27) are formed by a common elastic membrane (16), the two through slot openings (30, 31; 32, 33) has defined, elastically deformable valve flap sections (28; 29) which cooperate with corresponding bores (10, 24; 25, 20) axially aligned in pairs in the interior of the housing (1), the bores of each pair of bores the side of the respective shut-off valve to which the liquid or gas is to pass, the bore (24; 20) which is located has a larger cross section than the opposite bore (10; 25), the cross section of which is smaller than the size of the associated valve flap section (28 ; 29), and the edge of which forms the valve seat for the valve flap section. 2. Valve arrangement according to claim 1, characterized in that the housing (1) consists of two firmly connected housing parts (4, 6), between which one inside with a larger cross-section (24) bore and a ^' . Cross-sectionally smaller (25) bore for the two check valves (26; 27) provided intermediate plate (15) is inserted, against which the membrane (16) rests, the one, first housing part (4)

Intake connection part (2), with associated smaller bore (10) for the one check valve (2), and the outlet (3), with associated larger bore (20) for the other shutoff valve (27), while the other, second housing part (6) the pump connection part (5) and a connecting channel (34) for flow connection of the two bores (24, 25) in the intermediate plate (15) to the pump connection part (5).

X .. Valve arrangement according to claim 2, characterized in that the smaller cross-sectional bore (10) in one, first housing part (* 4) connects directly to a conical bore (9) of the suction connection part (2) provided with a Luer lock connection (7).

4. Valve arrangement according to claim 3, characterized in that the suction connection part (2) opposite pump connection part (5) of the other, second housing part (6) is also provided with a Luer lock connection (12) with a conical bore (35) which in the connecting channel (34) opens.

5. Valve arrangement according to claim 2, characterized in that the elongate intermediate plate (15) on one longitudinal side (22) has an eccentric projection (23) which fits into a corresponding groove (21) in one, the first housing part (4) ensure that the intermediate plate (15) is inserted in the correct direction.

6 ^' .. Valve arrangement according to claim 2, characterized in that the two housing parts (4, 6) are connected to one another by gluing.

7. Valve arrangement according to claim 2, characterized in that the two housing parts (4, 6) are connected to one another by welding.

8. Valve arrangement according to claim 2, characterized in that the housing parts (4, 6) consist of ABS plastic.

9. Valve arrangement according to claim 2, characterized in that the intermediate plate (15) consists of ABS plastic.

10. Valve arrangement according to claim 1, characterized in that the membrane (16) consists of silicone rubber.

11. Valve arrangement according to claim 1, characterized in that the edge of each smaller bore (10; 25) forming the valve seat is provided with a burr-shaped ring elevation (36) in order to additionally pretension the valve flap sections (28; 29) in the closed position.