Liquid dispensing device with a bearing surface for a spring

Abstract

The liquid distribution device (10) comprises a valve (16) comprising: - a flap-forming part (54), ensuring the blocking and passage of the liquid out of the device, and - a fixing edge (50), for the permanent fixing of the valve (16) relative to a reservoir (13), this fixing edge comprising a tubular fixing wall (50), sandwiched between an inner tubular wall (60) and an outer tubular wall (30).

Description

[0001] The invention relates to the field of dispensing liquid in the form of drops, in particular in the pharmaceutical field, for example ophthalmic or ear liquid.

[0002] Document US 5,154,325 already discloses a liquid distribution device, comprising an elastomer diaphragm forming a valve, arranged between a support and a cover mounted on the reservoir. The diaphragm comprises an annular peripheral bead and is held on the device by pinching this bead between the upper surface of the support and the lower surface of the cover. The diaphragm is therefore held in the device by pinching in the axial direction of the device.

[0003] A disadvantage of this type of assembly is that when a user presses the reservoir to release liquid, the liquid exerts pressure on the diaphragm in the axial direction to open it, and such pressure can cause liquid to leak around the periphery of the diaphragm. This risk of leakage is all the more likely if the parts have dimensions or relative positions that may vary, due to manufacturing tolerances. However, the presence of a leak in the device is troublesome, especially if the liquid does not contain a preservative, because liquid ends up in undesirable places in the device, which encourages the growth of bacteria and can subsequently contaminate the liquid.

[0004] The present invention aims in particular to provide a dispensing device in which sterility is improved.

[0005] To this end, the invention relates in particular to a liquid distribution device, comprising a valve comprising: a valve-forming part, ensuring the blocking and passage of liquid out of the device, and a fixing edge, for the permanent fixing of the valve relative to a reservoir, this fixing edge comprising a tubular fixing wall, sandwiched between an inner tubular wall and an outer tubular wall.

[0006] It is understood that the inner and outer tubular walls are arranged in such a way that they effect radial compression of the fixing wall of the valve, that is to say that they press on either side of the fixing wall, in the radial direction, corresponding to the direction perpendicular to the axis of the tubular walls, this radial compression ensuring sealing of the valve.

[0007] In other words, the distribution device comprises, in the valve attachment zone, three concentric tubes, possibly of short length, the inner tube corresponding to the inner tubular wall, the intermediate tube corresponding to the valve attachment wall and the outer tube corresponding to the outer tubular wall. These tubes all have the same axis, corresponding to the axis of the distribution device, this axis generally being an axis of revolution of the device, in particular of the reservoir, corresponding to the direction in which the liquid leaves the valve. It is understood that, to ensure satisfactory sealing, the diameter of the inner tubular wall is slightly greater than the diameter of the attachment wall, itself slightly greater than the diameter of the outer tubular wall.

[0008] By means of this radial pinching valve attachment, sealing is achieved by clamping in a direction other than the liquid ejection direction. Thus, when the liquid exits the device and exerts pressure on the valve so that it can assume its liquid passage configuration, the pressure exerted by the liquid, in the axial direction, is not exerted in the direction ensuring the sealing of the valve attachment. In other words, when it exits, the liquid exerts axial pressure on the valve, generating a relatively low stress in the radial direction of the valve. Also, the risk of displacement of the valve attachment elements, such as the inner and outer tubular walls, is relatively low.In any case, it is weaker than when the valve is fixed by tightening in the axial direction, which generally corresponds to the direction of assembly of the fixing elements, and which tends to move these fixing elements and therefore generate leaks. It is understood that the proposed configuration generates less stress on the part of the fixing elements, therefore a better seal, therefore a more sterile device and ensuring good operation.

[0009] The proposed device requires less precision in the dimensions of the fasteners. In fact, the clamping by means of the tubes guarantees a good seal, even if the components have relative positions that may vary slightly in the axial direction due to manufacturing tolerances or positioning tolerances during assembly in the axial direction.

[0010] Furthermore, since the assembly of the distribution device often takes place in the axial direction, the outer or inner tubular wall can advantageously constitute a centering wall of the valve, which facilitates its assembly.

[0011] Finally, it is noted that the use of tubular walls is advantageous in terms of compactness. Indeed, the axial position of the fixing zone can be moved further downstream of the distribution device, for example on either side of the valve-forming part, which can make it possible to reduce the diameter of the distribution nozzle. Furthermore, because the seal is provided by tubular walls, the compression surface area exerted by the fixing elements is increased, which provides better sealing.

[0012] It should be noted that the proposed device is very useful in cases where one wishes to distribute a liquid that does not contain a preservative. Indeed, with this type of liquid, compliance with the seal must be particularly reliable.

[0013] The device may further include one or more of the following features. The outer tubular wall is carried by a support attached to a reservoir. The support comprises a valve seat having substantially the shape of a disc, delimited by the outer tubular wall. Preferably, this outer tubular wall projects from the distal face of the disc (i.e. the face closest to the liquid dispensing end). Thus, the support has the general shape of a circular plate, the tubular part of which constitutes an edge having a sufficient height to be sandwiched between the inner and outer tubular walls. The valve seat further comprises a cylindrical central part, the distal end of which forms a support for the part of the valve forming a flap in the liquid blocking configuration. Also preferably, this central part projects from the distal face of the disc. The valve comprises a web delimited at its periphery by the fixing wall.The valve further comprises a cylindrical central portion, projecting from the veil, and the distal end of which is the flap-forming portion of the valve. Thus, the valve has a shape complementary to a portion of the support. The inner tubular wall is carried by a cap attached to a reservoir, at least partially covering the valve. Preferably, this cap comprises a central orifice crossed by the distal end of the valve. The cap comprises a groove delimited by the inner tubular wall, a bottom and an outer casing, this groove sandwiching the valve fixing wall and the outer tubular wall. The device comprises means for snap-fastening the cap onto the support. Preferably, this snap-fastening is a snap-fastening in the axial direction, that is to say that the parts are brought together in the axial direction to snap them together.The latching means are configured such that the latching further corresponds to the permanent fixing of the valve by pinching between the inner tubular wall and the outer tubular wall. The flap-forming part of the valve and the fixing edge of the valve are made of elastomeric material. The valve has a rigid part, preferably serving as a bearing surface for a spring.

[0014] The invention also relates to a method of assembling the device, comprising the following successive steps: installing the valve on a support, by inserting the valve mounting wall inside the outer tubular wall, installing a cover over the valve, by inserting the inner tubular wall inside the valve mounting wall, and snapping the cover onto the support.

[0015] Optionally, provision may be made for the insertion of a spring between the step of installing the valve on the support and the step of installing the cover above the valve, the spring being inserted around a central cylindrical portion of the valve.

[0016] The invention will be better understood from reading the following description, given solely by way of example and with reference to the drawings in which: there figure 1 is a sectional view of a dispensing device according to one embodiment; and the figures 2a à 2d are perspective views illustrating the assembly process of the device of the figure 1 .

[0017] It has been represented on the figure 1 a device 10 for dispensing liquid in the form of drops. The dispensed liquid is, in this example, a pharmaceutical liquid, such as ophthalmic or ear liquid. The device 10 comprises a dispensing tip 12, mounted by screwing onto the neck of a reservoir 13. The device 10 is configured so as to dispense liquid following pressure exerted by the user on the reservoir 13. In this example, the reservoir is elastically deformable, so as to resume its shape after pressure exerted by the user. The device 10, at least the reservoir 13, has an axis X of revolution, also corresponding to the direction of liquid ejection.

[0018] The nozzle 12 comprises a support 14, a valve 16, a spring 17, a cover 18 and a hydrophobic filter 20.

[0019] The support 14 comprises, in this example, a part 22, arranged at the proximal end of the tip, for fixing the support to the reservoir 13. This part 22 comprises an external skirt 24, threaded so as to be screwed onto the neck of the reservoir 13, and an internal skirt 26, of tubular shape, making it possible to ensure sealing between the reservoir 12 and the dispensing tip 10.

[0020] The support 14 also comprises an intermediate part 28, forming a seat for the valve 16. This intermediate part 28 has substantially the shape of a disc, extending in a radial plane R perpendicular to the axis X. The disc 28 is delimited, on its distal face, by an external tubular wall 30. This wall forms a peripheral skirt of the disc 28, it extends perpendicular to the disc 28, in the form of a tube of axis X, sufficiently high to receive the valve 16, as described below. The disc 28 comprises, in the lower vicinity of the tubular wall 30, an annular rib 32, making it possible to delimit a centering and receiving groove for the edge of the valve 16. The disc 28 also comprises a cylindrical central part 34 for closing the valve, projecting from its center, on the distal side of the disc 28 and carrying, at its distal end, a surface 36 for supporting the valve 16.This part 34 forms a closing pin allowing the opening or closing of the valve 16. The disc 28 is also crossed by a channel 38 for the passage of liquid coming from the reservoir. This channel 38 opens onto a cavity 40, delimited in particular by a recess made on the distal surface of the disc 28. This cavity 40 also opens onto a second channel 42 for the passage of liquid, delimited by the pin 34 and the valve 16. The channels 38 and 42 have an axis substantially parallel to the axis X. As can be seen in the . figure 1 , the disc 28, the outer tubular wall 30 and the closing pin 34, define a tubular cavity for receiving the valve 16.

[0021] Furthermore, the support 14 comprises a channel 44 for the passage of air into the reservoir, this channel 44 opening onto a housing 46 for receiving the hydrophobic filter 20, this housing 46 being cylindrical, open at its proximal end for the insertion of the filter 20.

[0022] The valve 16 comprises a central cylindrical part 48, an annular peripheral skirt 50, the central part 48 and the skirt 50 being connected to each other by a web of material 52. The web 52 carries, on its distal surface, a seat 53 for supporting the spring 17. The distal part 54 of the central part 48 is a valve-forming part, ensuring the blocking and passage of liquid, by cooperation with the bearing surface 36. Thus, the surface 36 forms a support for the valve-forming part 54 when the latter is in the liquid blocking configuration. The upper surface of the part 48 comprises a channel 56 for ejecting the liquid, opening onto a drop metering form 58.

[0023] The skirt 50 forms a fixing edge of the valve 16 on the support, for the permanent fixing of the valve relative to the reservoir 13. It consists of a fixing wall 50, tubular with axis X, with a diameter slightly greater than the internal diameter of the external tubular wall 30.

[0024] In this example, the valve 16 is entirely made of an elastomer material. However, it is possible to provide that the valve comprises certain parts made of an elastomer material and other parts made of a more rigid material, in particular the part 53 forming a support for the spring 17. Preferably, the part forming a valve 54, the web 52 and the fixing wall 50 are made of an elastomer material.

[0025] The cover 18 is snap-fastened onto the support 16 by means of snap-fastening means 59. The snap-fastening means 59 make it possible to snap-fasten the cover 18 relative to the support 14 following assembly in the axial direction X. It carries an inner tubular wall 60, with an axis X and a diameter slightly greater than the diameter of the fixing wall 50 of the valve. The cover 18 also comprises an outer casing 62 forming an outer skirt, extending towards the proximal direction relative to the rest of the cover 18, as well as a base 64, such that the wall 60, the base 64 and the casing 62 delimit a groove intended to sandwich the fixing wall 50 and the outer tubular wall 30. The cover 18 largely covers the valve 16, while however being crossed in its center by the central part 48 of the valve.For this purpose, the cover 18 delimits a cylindrical cavity by means of a tubular inner skirt 66, having a function of centering the valve 16. The skirt 66 also delimits a groove 68 forming a support seat for the spring 17.

[0026] The operation of the device 10 will now be described.

[0027] When a user presses on the reservoir 13, he exerts pressure on the fluid which cannot pass through the hydrophobic filter 20 and flows into the channel 38 then into the cavity 40 and into the channel 42.

[0028] The pressure of the fluid in the channel 42 deforms the valve-forming part 54, so as to make it pass from its liquid-blocking configuration to a liquid-passing configuration, by detachment of the part 54 from the bearing surface 36. This deformation is facilitated by the compression of the spring 17 under the pressure of the liquid. The liquid is then distributed in the form of drops.

[0029] The assembly of the device will now be described, with reference to figures 2a à 2d .

[0030] The assembly comprises a step of assembling the end piece 12, followed by a step of screwing this end piece 12 onto the reservoir 13.

[0031] The assembly of the tip 12 begins with a step of installing the valve 16 on the support 14, by inserting the fixing wall 50 of the valve inside the tubular wall 30 of the support 14. This step is illustrated in the figure 2a , it is followed by a step of inserting the spring 17 around the central part 48 of the valve, illustrated in the figure 2b . Once the spring is in place, we move on to a step of installing the cover 18 above the valve 16, illustrated in the figure 2c , by inserting the inner tubular wall 60 inside the fixing wall 50. This installation of the cover 18 is completed by snapping the cover onto the support 14, illustrated in the figure 2d , this snap-fastening being simultaneous with the permanent fixing of the valve 16 on the end piece 12, sandwiched between the inner 60 and outer 30 tubular walls. It will be noted that when the valve 16 is fixed on the device, the web 2 is put under elastic stress so as to press the end 54 against the surface 36. This pressing is further facilitated by the return force of the spring.

[0032] Among the advantages of the device, it is understood that the static sealing produced around the fixing wall 50, by pinching the walls 60 and 30, is particularly effective. Indeed, when the liquid escapes from the reservoir 13, it exerts pressure on the valve 16 in the direction X, and this pressure in the direction X is not reflected on the fixing part 50, the fixing of the valve being ensured by compression in the radial direction R.

[0033] It will be noted that the invention is not limited to the embodiments previously described.

Claims

1. Liquid distribution device (10), characterized in that it comprises a valve (16) comprising: - a part (54) forming a flap, ensuring the blocking and the passage of liquid out of the device (10), and - a fixing edge (50), for the permanent fixing of the valve (16) relative to a reservoir (13), this fixing edge comprising a tubular fixing wall (50) sandwiched between an inner tubular wall (60) and an outer tubular wall (30) which effect radial compression of the fixing wall (50), and - a rigid part serving as a bearing surface for a spring (17), the outer tubular wall (30) being carried by a support (14) attached to the reservoir (13).

2. Device (10) according to claim 1, which comprises a valve seat (28) comprising a cylindrical central portion (34), the distal end of which forms a support (36) for a portion (54) of the flap valve (16) in the liquid blocking configuration.

3. Device (10) according to the preceding claim, in which the valve seat (28) is formed by the support and has substantially the shape of a disc, delimited by the outer tubular wall (30).

4. Device (10) according to any one of the preceding claims, in which the valve (16) further comprises a central portion projecting from a web (52) and the distal end of which is the flap-forming portion of the valve (16).

5. Device (10) according to any one of the preceding claims, comprising means (59) for snapping a cover (18) and the support (14).

6. Device (10) according to the preceding claim, wherein the latching means (59) are arranged so that the latching takes place in the axial direction.

7. Device (10) according to any one of the preceding claims, in which the valve (16) comprises a cylindrical central part (48) extending closer, along a main axis of the device (10), to a free end of the device (10) used for dispensing the liquid than the outer tubular wall (30), one end of the cylindrical central part (48) being the flap-forming part (54) of the valve.

8. Device (10) according to claim 7, in which the cylindrical central part (48) extends closer, along the main axis of the device (10), to the free end of the device (10) used for dispensing the liquid than the inner tubular wall (60).

9. Device (10) according to any one of the preceding claims, forming a device for dispensing pharmaceutical liquid, in particular ophthalmic or auricular.

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