WO2009095586A2

WO2009095586A2 - Fluidic duct structure and cassette for peristaltic pump

Info

Publication number: WO2009095586A2
Application number: PCT/FR2009/050085
Authority: WO
Inventors: Jean-Marc Andre; Grégory PEALA
Original assignee: Corneal Innovation
Priority date: 2008-01-24
Filing date: 2009-01-22
Publication date: 2009-08-06
Also published as: FR2926855A1; EP2247856A2; WO2009095586A3

Abstract

The invention relates to a fluidic duct structure for the cassette of a peristaltic pump, that comprises: a duct-forming assembly (22) made in a rigid plate (16); two connection means (28, 30) connected to said duct-forming assembly; a deformable piping (36) extending outside said plate and having two ends (36b, 36c) respectively connected to said connection means, said piping including a portion substantially in the shape of a semi-circle for cooperation with the rotor (82) of the peristaltic pump; and connection means (86, 90, 92) of said duct-forming assembly for connecting said ducts to fluidic components to be mounted on the cassette. The duct-forming assembly comprises a hollow pattern (40) giving into a surface of the plate (16) and a thin film (26) tightly attached on the surface of the plate opposite the hollow pattern.

Description

Fluidic conduit structure and cassette for peristaltic pump

The present invention relates to a fluidic conduit device intended to be integrated in a cassette associated with a peristaltic pump and a cassette using said conduit structure.

The present invention can be used in particular but not exclusively for equipment for implementing the phacoemulsification technique. This technique is used to implement the so-called "cataract" operation which consists, initially, in breaking up the crystalline nucleus of a patient's eye and then sucking in the crystalline fragments to leave only the capsular bag in which is placed the crystalline nucleus. At the same time, a liquid must be injected into the patient's eye to compensate for the liquid that is sucked in at the same time as the debris is extracted from the eye by aspiration.

The aspiration of the crystalline nucleus debris is most often carried out using a peristaltic pump associated with a cannula or handpiece placed in the eye through an incision of reduced dimensions. Peristaltic pumps are of a well-known type and it is therefore not necessary to describe them in detail. Such a pump is described in particular in European patent EP 1 099 854. It is essentially constituted by a deformable pipe portion in the general shape of a circular arc on which acts a rotor equipped with rotary rollers acting with pressure on the deformable wall of driving. The action of the rollers on this pipe causes the displacement of the liquid present in the pipe. This pipe, of course, is connected by a first tube to the cannula or handpiece and a second tube which opens into a storage tank of debris and liquid sucked. As already indicated, it is desirable to also provide other pipes to replace as the liquid sucked into the eye, by injecting a replacement liquid. This injection is most often performed by the handpiece itself.

It is known to constitute in particular the pipe on which act the rotor rollers of the peristaltic pump, to design the pump in two parts, on the one hand a removable rotor and on the other hand a a structure which defines in particular the pipe in the form of an arc of a circle, the duct of which the wall is of course deformable.

The portion of the peristaltic pump which defines in particular the deformable conduit on which the rotor is operating and which more often than not also defines other lines and other means of connection of device attached to the peristaltic pump is often referred to as a cassette.

The European patent mentioned above describes a peristaltic pump and a cassette in particular usable for the phacoemulsification which has been defined above. In this patent, the cassette, and more particularly the pipe element on which the rotor of the peristaltic pump acts, is constituted on the one hand by a frame including the half of the driving element and on the other hand by a plastic film which has a thicker portion defining the other half of the pipe element. This plastic film is fixed on the face of the frame in which opens the recess defining a portion of the tube. The film of plastic material is glued or fixed on the face of the frame by any suitable means.

Providing on the one hand the mechanism of the rotor of the peristaltic pump and on the other hand a cassette which defines the different lines in which the liquid drawn and the liquid injected to the patient will circulate, makes it possible to consider it as disposable, if it is desired, the cassette which of course can be affected by the circulation of this liquid while retaining the mechanical part and more particularly the rotor of the peristaltic pump. In the known embodiment described above, a problem consists in the production of the plastic film, a part of which must constitute a semi-cylindrical surface in the form of an arc-shaped axis defining half of the conduct of the peristaltic pump. Moreover, the fixing, in particular by gluing, of the plastic film on the face of the frame raises a certain number of problems, and in particular sealing. Indeed, a significant pressure is exerted by the rotor rollers of the peristaltic pump on the associated driving element and the risk of leakage are therefore significant. Finally, this duct structure does not ensure that its internal diameter is perfectly constant. However, it is the constancy of this diameter that makes it possible to control the accuracy of the flow rate of the pump. A first object of the invention is to provide a conduit structure which allows a simpler and more precise way to define in particular the duct structure to cooperate with the rotor of the peristaltic pump conferring a substantially constant internal diameter on all its length.

To achieve this object, according to the invention, the fluidic conduit structure intended to be integrated in a cassette associated with a peristaltic pump, comprises:

a duct assembly formed in a rigid plate having an end edge;

two connection means disposed in said edge and connected to said duct assembly;

- A deformable tubing extending from said plate whose two ends are respectively connected to said connecting means, said tubing having a substantially semicircular portion to cooperate with the rotor of the peristaltic pump; and

a plurality of connection means of said duct assembly for connecting said ducts to fluid components intended to be mounted on the cassette, said connection means being mechanically integral with said plate.

In addition, in this structure of fluid ducts, the duct assembly is constituted by a recessed relief formed or opening into a face of the plate and a thin film or piece fixed (e) sealingly on said face of the plate facing the relief. It is understood that thanks to the duct structure according to the invention, the deformable tubing which cooperates with the rotor of the peristaltic pump is constituted in one piece which thus guarantees a very good seal. Indeed, it is the two ends of this deformable tubing which are connected to end pieces made in the rigid plate of the duct structure. In addition, since the tubing is an independent piece, it can be obtained by molding silicone. This manufacturing technique makes it possible to control with very great precision the internal diameter.

In addition, the deformable tubing being outside the rigid plate of the conduit structure, it is possible to place it in the rigid support of the cassette of the peristaltic pump so that the rotor of the peristaltic pump acts effectively on the deformable tubing.

Finally, the duct assembly is constituted by a recessed relief formed in a face of the plate and a thin film sealingly attached to said face of the plate facing the recessed relief. Thus, the ducts are formed between the face of the plate and the thin film. With this arrangement, the realization of the circuit assembly is particularly simple. Indeed, the ducts are formed in a single face of the plate, which allows the use of a single mold for the manufacture thereof by injection molding. The other face of the plate can thus remain flat, or if necessary also be formed or molded to fulfill other functions. The ducts are formed by sealingly fixing the thin film on the plate, facing the recessed relief. Thus, advantageously the duct assembly is formed with only two different parts, a plate shaped on one side, and a thin film.

In some embodiments, the thinness of the thin film - or at least the presence of areas of reduced thickness in the thin film - makes it possible to perform functions through the film, the film being deformable or at least locally deformable, c that is, deformable in areas of reduced thickness. These functions may include pressure measurement, and / or flow authorization / interruption functions. Performing these functions through the thin film advantageously allows to preserve the tightness of the duct assembly.

Preferably, the thin film is removable, which allows its replacement, or the inspection or cleaning of the ducts. Preferably, the thin film is silicone. More preferably, the conduit structure defines an area of larger dimensions than said ducts, said area being sealed by said thin film, said area constituting a pressure measuring region.

Preferably, an area of the thin film has a small thickness and is arranged to form a pressure measurement zone. A second object of the invention is to provide a peristaltic pump cassette which utilizes the conduit structure defined above.

According to the invention, the cassette for a peristaltic pump is characterized in that it comprises:

a conduit structure according to the structure defined above;

a rigid support comprising means for securing the support to the plate of the duct structure and for maintaining a constant distance between said plate and the support; and

- Means for fixing the deformable tubing on said support to give it a fixed shape as to its longitudinal axis.

Other features and advantages of the invention will appear better on reading the following description of a preferred embodiment of the invention given by way of non-limiting example. The description refers to the appended figures in which:

- Figure 1 is an exploded view of the main components of the cassette of the peristaltic pump showing in particular the conduit structure according to the invention; FIG. 2 is a perspective view of the cassette of the assembled peristaltic pump;

- Figure 3 is a sectional view along line HI-III of Figure 2;

- Figure 4 is a sectional view along the line IV-IV of Figure 2;

- Figure 5 is a sectional view along the line V-V of Figure 2;

FIG. 6 is a view from above of the assembled cassette showing in dashed lines the placement of the rotor of the peristaltic pump;

- Figure 7 is a top view of the cassette;

- Figure 8 is a view of an additional structure of the cassette for mounting on the cassette of the peristaltic pump itself and some ancillary components of said pump; and - Figure 9 is a perspective view showing the complete cassette equipped with the peristaltic pump and ancillary organs.

Referring first to Figures 1 to 5, a preferred embodiment of the peristaltic pump cassette will be described. As best shown in Figure 1, the cassette which bears the general reference 10 is constituted by a rigid support 12 made, for example, of polycarbonate and a conduit structure 14 which will be called later "cartridge".

The cartridge 14 is intended to be placed in the rigid support 12 to thereby constitute the assembly of the cartridge adapted to cooperate with the peristaltic pump.

The cartridge 14 is essentially constituted by a plate 16 formed of a rigid material, preferably a polycarbonate, which has an end face 18 and an upper face 20. In the upper face 20, recessed reliefs are provided with the general reference 22 These hollow reliefs 22 are made in a countersink 24 opening into the face 20 of the rigid plate. The countersink 24 may be closed by a removable part 26 made preferably of silicone. The end face 18 of the rigid plate 16 is equipped in its thickness with two connecting ends respectively referenced 28 and 30. These end pieces communicate with pipes 32, 34 made in the thickness of the plate 16 and which will be described later. . On the end pieces 28 and 30 is connected a tubing 36 which has a first part 36a in the shape of a semicircle and rectilinear branches 36b and 36c. The ends of the branches 36b and 36c are connected to the end pieces 28 and 30. The end pieces 28 and 30 could be replaced by other connecting means of the ends of the tubing 36. These could be holes capable of receiving by wedging them. ends of the tubing. As seen in Figure 1, the underside of the tubing 36 is provided with a rib 38 which projects out of the wall of the tubing 36. The function of this rib 38 will be explained later. As already indicated, the tubing 36 is preferably obtained by molding silicone. This manufacturing technique makes it possible to guarantee, on the internal diameter of the tubing, a accuracy of the order of 2/100 ^th of mm. The tubing 36 could also be made by extrusion obtaining similar performance.

In the countersink 24, the different grooves 22 consist essentially of a central groove 40 which constitutes a conduit for the circulation of liquid and which comprises an interruption 42 for the reasons which will be explained later and two lateral grooves 44 and 46 for receiving a fixing groove 46 formed in the inner face 26a of the additional part 26. These grooves also define a recess of generally circular shape 48 which communicates with the pipe elements 34 and 40 and which is intended to receive a pressure sensor as well as that will be explained later. The recess 48 is surrounded by a substantially circular groove 50 for receiving the circular portion 52 of the rib 40 of the additional piece 26.

It is thus understood that, when the additional piece 26 is put into place in the counterbore 24 of the cartridge 14 and fixed thereto by the cooperation of the ribs 46 and grooves 44 and 45, the groove 44 effectively constitutes one or more ducts. conduits whose function will be explained later.

If we return to the rigid plate 12 or rigid support which with the cartridge 14 constitutes the cassette 10, we see that it has an upper face 60 in which is formed a housing 62 for receiving the rigid plate 16, a resilient clipping system not shown allows to maintain the cartridge 14 in the housing 62. In the upper face 60 of the rigid support 12 is formed a groove of substantially semicircular shape 64 which is opposite the tubing 36 when the cartridge 14 is placed in the housing 62. This groove 64 is intended to receive the rib 38 of the tubing 36 to immobilize the tubing 36 relative to the rigid support 12 and thus allow, as will be explained later cooperation between tubing 36 and the rotor rollers of the peristaltic pump.

In Figure 1, we also see that the bottom 64 of the housing 62 of the rigid support 12 is pierced with a number of orifices 66, 67, 68 and 69 whose function will be explained later. FIG. 5 shows in more detail the attachment of the tubing 36 to the rigid support 12 thanks to the cooperation of the rib 38 and the groove 64 formed in the upper face 60 of the rigid plate 12.

In Figure 3, there is shown in more detail the cooperation between the removable part 26 and the rigid plate 16 of the cartridge. In this figure, it is more specifically shown how the circular recess 48 is made to allow the measurement of the pressure of the fluid flowing in the inner pipe 34 and in the pipe 40. In this region, the removable part 26 comprises in addition to the rib 52 a portion of reduced thickness 70 extending above the recess 48 formed in the rigid plate 16. The portion 70 has preferably a thickness of the order of 0.25 mm. As already explained, in this area, the removable part 26 is secured to the rigid plate 16 by the cooperation of a substantially circular rib 52 with a groove 50 formed in the countersink 24. As will be explained later , it is thus possible to place against the part 70, which forms a very thin skin, the removable part 26, a pressure sensor, this sensor being able to measure through the wall of reduced thickness 70.

In Figure 4, there is shown in more detail the cooperation between the removable part 26 and the rigid plate 16 of the cartridge in a connection area between the channel groove 40 and a connecting port. In this zone, the removable part 26 comprises in addition to the ribs 44 and 45 already described a slightly convex portion 72.

In FIG. 6, the completely assembled cartridge 10 is represented with its rigid support 12 in which the cartridge 14 is clipped. To better demonstrate the invention, the removable part 26 has not been put in place. in this figure, there is shown, in dashed lines, the position of the rollers 80 of the peristaltic pump 82 which act on the semicircular-shaped portion 36a of the tubing 36.

In this figure, it can also be seen that the end 36b of the tubing 36 which is connected to the internal pipe 30 is connected via the latter to a fluidic connection socket 84 corresponding to the bore 69 which is connected to a pipe. tubing opening into a bag for collecting debris and liquid. This figure also shows better that the branch 36c of the tubing is connected to the pipe internal 34 itself connected to the annular recess 48 for taking pressure. Beyond the recess 48, there is the channel groove 40 which is connected to a connection terminal 86 corresponding to the bore 66 which is connected to a tubing, itself connected to the suction portion of the handpiece. As already explained, the groove 40 is divided into two portions, a first portion 40a and a second portion 40b separated by a wall 88, the portion 40b of the groove 40 is connected to fluid connectors 90 and 92 corresponding to the holes 67 and 68 whose function will be explained later. _F in Figure 9 is shown the complete cassette consisting of the cassette 10 itself already described and a metal plate 93 on which is articulated about the axis 94 Ia lower part of the cassette. This plate 93 serves as a mechanical support for mounting various components and in particular the motor and the rotor of the peristaltic pump 82 of a pressure sensor 96 which is arranged opposite the portion of reduced thickness 70 of the removable part 26. In this figure, the connection ends of the cassette, such as 100, 102, 104 and 106, are also shown, which make it possible to mount the appropriate pipes, in connection with the connection terminals already described, of the ducts, in order to allow the operation of the phacoemulsification plant and in particular the extraction of the crystalline debris by pumping out of the patient's eye and the injection of the replacement liquid. These terminals respectively correspond to the connecting lines to the collection bag, the irrigation line, the infusion line and the suction line connected to the chip by hand.

Of course, other guiding and securing means may be used in the context of the invention between the cassette 12 and the metal plate 39.

It goes without saying that the ducts defined in particular by the grooves 40, 40a, 40b or the circular recess and by the removable part 26 could be made differently. Similarly, these conduits could consist only in the connection of the tube associated with the cannula with the peristaltic pump and in the connection of the peristaltic pump with the storage tank of the liquid and crystalline debris sucked, the injection into the eye replacement saline being made by other means external to the cassette. According to the preferred embodiment described, the cartridge 14 is removable relative to the support 12 of the cassette. Thus, it is possible to change only the cartridge. However, it would not go beyond the invention if the cartridge was secured to the support of the cassette or if these two elements were one and the same piece.

Claims

A fluidic conduit structure for integration into a cassette associated with a puncture pump, comprising: a conduit assembly (22) formed in a rigid plate (16) having an end edge (18);

two connection means (28, 30) disposed in said end edge and connected to said duct assembly;

a deformable tubing (36) extending out of said plate whose two ends (36b, 36c) are respectively connected to said connecting means, said tubing having a substantially semicircular portion to cooperate with the rotor (82); ) of the puncture pump; and

a plurality of connection means (86, 90, 92) of said duct assembly for connecting said ducts to fluidic components intended to be mounted on the cassette, said connecting means being mechanically integral with said plate; said structure being characterized in that the duct assembly is constituted by a recessed relief (40) opening into a face of the plate (16) and a thin film (26) sealingly attached to said face of the plate look at the relief.

2. Duct structure according to claim 1, characterized in that said thin film (26) is removable.

3. Duct structure according to claim 1 or 2, characterized in that said recessed relief defines an area of larger dimensions (48) than said ducts, said area being sealed by said thin film (36), said zone constituting a region of pressure measurement.

4 conduit structure according to any one of claims 1 to 3, characterized in that said tubing (36) is made by molding

5 pipe structure according to any one of claims 1 to 3, characterized in that said pipe (36) is made by extrusion

6. Duct structure according to any one of claims 4 and 5, characterized in that said tubing (36) is silicone.

7. Duct structure according to any one of claims 1 to

6, characterized in that said connecting means are end pieces (28, 30) protruding out of said end edge of the plate and in that the ends (36b, 36c) of said tubing (36) are engaged on said tips.

Conduit structure according to one of claims 1 to

7, characterized in that a zone of the thin film has a small thickness and is arranged to constitute a pressure measurement zone.

9. Cassette for peristaltic pump, characterized in that it comprises:

a duct structure according to any one of claims 1 to 8,

a rigid support (12) comprising means for securing said support (12) to said plate (16) of the duct structure (12), and for maintaining a constant distance between said plate and said support; and

means (38, 64) for fixing said deformable tubing on said support.

10. Cassette according to claim 9, characterized in that, to fix said tubing on said support, it comprises a rib projecting from the portion of the tubing in substantially semicircular shape and a groove in a face said support and adapted to receive said rib.