Liquid dispensing device

Abstract

A liquid dispensing device includes a dispensing end piece and a neck of a reservoir for storing the liquid, the end piece being attached to the neck, which has a tubular internal surface. The end piece has a tubular internal skirt that is mounted in the neck and defines, with the internal surface, at least one annular sealing zone, preventing the liquid from passing between the internal skirt and the neck. The skirt defines, with the internal surface, a separate zone for retaining shavings, which prevents shavings that are formed in the sealing zone while the end piece is being fitted into the neck from getting into the reservoir.

Claims

1. A liquid dispensing device, characterized in that it comprises a dispensing end piece and a neck of a reservoir for storing the liquid, the dispensing end piece being attached to the neck by screwing, the neck having an internal surface of substantially tubular general shape, the dispensing end piece having an internal skirt which is mounted inside the neck of the reservoir and which defines, with the internal surface of the neck, at least one annular sealing zone such that liquid present in the reservoir cannot pass between the internal skirt of the dispensing end piece and the neck of the reservoir, the internal skirt of the dispensing end piece defining, with the internal surface of the neck, a separate chips retention zone arranged upstream of the sealing zone with respect to the reservoir, the chips retention zone being configured such that chips formed at the sealing zone while the dispensing end piece is being assembled on the neck of the reservoir cannot get into the reservoir, wherein the dispensing end piece comprises a threaded surface which engages, by screwing, with a threaded surface on the neck during mounting of the device and is not detached therefrom during normal use.

2. The device as claimed in claim 1, wherein the internal surface of the neck of the reservoir has a general diameter and it comprises a convex annular shape projecting from the internal surface of the neck so as to define a reduced diameter with respect to the general diameter of the neck of the reservoir and thus to form, by cooperation with the internal skirt of the dispensing end piece, the chips retention zone.

3. The device as claimed in claim 2, wherein the reduced diameter is smaller than the diameter of the neck of the reservoir at the sealing zone.

4. The device as claimed in claim 1, configured such that, when assembling of the dispensing end piece on the neck of the reservoir, the internal skirt of the dispensing end piece comes into contact with the internal surface of the neck of the reservoir first at the sealing zone and then at the chips retention zone.

5. The device as claimed in claim 4, wherein the neck of the reservoir has a length (L.sub.neck min) delimited by an upper end of a length of the neck providing sealing (L.sub.neck sealing) and an upper end of a length of the neck providing the chips retention zone (L.sub.neck retention), the dispensing end piece has a length (Lend.sub.piece max) delimited by a lower end of a length of the end piece providing sealing (Lend.sub.piece sealing) and a lower end of a length of the end piece providing the chips retention zone (Lend.sub.piece retention), and wherein L.sub.neck min>Lend piece max.

6. The device as claimed in claim 1, wherein the internal surface of the neck of the reservoir at the sealing zone is substantially plane, sealing with the internal skirt of the dispensing end piece being realized by face-to-face contact of the internal skirt of the dispensing end piece with the internal surface of the neck of the reservoir.

7. The device as claimed in claim 1, wherein the internal surface of the neck of the reservoir at the sealing zone comprises an annular bead.

8. The device as claimed in claim 1, wherein the internal surface of the neck of the reservoir comprises, downstream and in the direct vicinity of the sealing zone, an annular recess.

9. The device as claimed in claim 1, wherein the neck of the reservoir is made of low density polyethylene and the internal skirt of the dispensing end piece is made of high density polyethylene.

10. The device as claimed in claim 1, wherein the end of the internal skirt of the dispensing end piece situated on the side facing the reservoir has a funnel shape.

11. The device as claimed in claim 2, wherein the internal surface of the neck of the reservoir at the sealing zone comprises an annular bead.

12. The device as claimed in claim 3, wherein the internal surface of the neck of the reservoir at the sealing zone comprises an annular bead.

13. The device of claim 1, wherein the dispensing end piece has an external skirt surrounding the internal skirt, wherein the threaded surface of the dispensing end piece is on an inner side of the external skirt.

14. A liquid dispensing device, characterized in that it comprises a dispensing end piece and a neck of a reservoir for storing the liquid, the dispensing end piece being attached to the neck by screwing, the neck having an internal surface of substantially tubular general shape, the dispensing end piece having an internal skirt of substantially tubular general shape which is mounted inside the neck of the reservoir and which defines, with the internal surface of the neck, at least one annular sealing zone such that liquid present in the reservoir cannot pass between the internal skirt of the dispensing end piece and the neck of the reservoir, the internal skirt of the dispensing end piece defining, with the internal surface of the neck, a separate chips retention zone arranged upstream of the sealing zone with respect to the reservoir, the chips retention zone being configured such that chips formed at the sealing zone while the dispensing end piece is being assembled on the neck of the reservoir cannot get into the reservoir, wherein the dispensing end piece has a threaded surface which engages, by screwing, with a threaded surface on the neck during mounting of the device and is not detached therefrom during normal use.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be better understood on reading the following description given solely by way of example with reference to the drawings, in which:

(2) FIG. 1 is a sectional view in longitudinal direction of a device according to a first embodiment,

(3) FIG. 2 is a view, similar to FIG. 1, of a device according to a second embodiment,

(4) FIG. 3 is a view, similar to FIG. 1, of a device according to a third embodiment,

(5) FIG. 4 is a schematic view illustrating the relative positions of the sealing zones and the chips retention zones, and

(6) FIG. 5 is a sectional view in longitudinal direction of the reservoir of the device of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIG. 1 illustrates a device 10 for dispensing liquid in the form of drops that comprises a reservoir 12 to which is attached a dispensing end piece 14 over which a protective cap 18 (visible in FIG. 2 or FIG. 3) can be mounted. The reservoir 12 comprises a neck 38 for receiving the dispensing end piece 14.

(8) The dispensing end piece 14 has an upper dispensing end 20 in which an orifice 16 is formed for dispensing calibrated drops, in this example, by drops formation means 16. More precisely, again in this example, the dispensing end piece 14 is of substantially cylindrical general shape. The dispensing end piece 14 here comprises a drop dispensing valve 22 made of elastomer material so as to take, under the pressure of the liquid (when the user presses on the reservoir 12), a liquid passage configuration. The dispensing end piece 14 further comprises a valve support 24, attached to the reservoir 12, bearing a pin 26 forming a seat against which the valve 22 is pressed and also comprising an air passage duct 28 shut off by an air-permeable member 30 preventing bacteria from entering into the reservoir 12. The dispensing end piece 14 also comprises a return element 32 allowing the valve 22 to be returned into a liquid blocking configuration. Finally, the dispensing end piece 14 comprises a cover 34 for pressing the valve 22 against the support 24.

(9) More precisely, the valve support 24 comprises an internal skirt 40 of substantially tubular general shape, which is mounted inside the neck 38 of the reservoir 12, and also an external skirt 41 surrounding the neck 38 of the reservoir 12 and having, for example, a tapped surface for screwing the dispensing end piece 14 onto the reservoir 12. The tapped surface is situated on the inner side of the external skirt 41. The internal skirt 40 has a lower end of funnel shape in order to facilitate the insertion of the dispensing end piece 14 into the neck 38 of the reservoir 12. In the device 10 of FIG. 1, the neck 38 has a substantially tubular internal surface 42 having a general diameter and comprising an annular bead 44. The annular bead 44 forms a sealing zone 46 with the internal skirt 40 of the dispensing end piece 14. When screwing the dispensing end piece 14, the internal skirt 40 comes into contact with the annular bead 44 at a high speed, which can generate chips of plastics material, for example in the form of filaments, which risk falling into the reservoir 12 and contaminating the liquid contained in the reservoir 12.

(10) The internal surface 42 of the neck 38 further comprises a convex annular shape 48 projecting from the internal surface 42 of the neck 38 so as to define a reduced diameter with respect to the general diameter, referred to as chips retention diameter D.sub.R, represented in FIG. 1. This chips retention diameter D.sub.R is smaller than the general diameter D of the neck 38 of the reservoir 12, and also smaller than the diameter D.sub.E of the neck 38 of the reservoir 12 at the sealing zone 46, referred to as sealing diameter D.sub.E. This convex shape 48 produces, by cooperation with the internal skirt 40 of the dispensing end piece 14, a chips retention zone 50. When the dispensing end piece 14 is mounted on the neck 38 of the reservoir 12, by screwing, the chips created by friction between the neck 38 and the skirt 40 in the sealing zone 46 are blocked in this chips retention zone 50 and cannot fall into the reservoir 12. It will be understood that the neck 38 of the reservoir has a threaded external surface in order to screw the dispensing end piece 14 onto the reservoir 12, by cooperation with the tapped surface of the external skirt 41.

(11) In the embodiment in FIG. 2, the internal surface 42 of the neck 38 does not comprise an annular bead but is substantially plane in the sealing zone 46. In this example, sealing between the internal surface 42 and the internal skirt 40 is achieved by face-to-face contact, in this instance a cylinder-against-cylinder contact of the two tubular surfaces of the skirt 40 and the internal surface 42. The internal surface 42 of the neck 38 also comprises a convex annular shape 48 projecting from the internal surface 42 so as to form, by cooperation with the internal skirt 40 of the dispensing end piece 14, a chips retention zone 50. In this case, the contact surface is more extensive, without pointed contact, the risk of creating chips is thus reduced.

(12) In FIG. 3, sealing between the internal surface 42 and the internal skirt 40 is also provided by cylinder-against-cylinder contact. Unlike the example illustrated in FIG. 2, the internal surface 42 of the neck 38 comprises, downstream and in the direct vicinity of the sealing zone 46, an annular recess 52. As the chips are created in the sealing zone 46, it is preferable that the contact surface in the sealing zone 46 is as localized as possible. Thus, the screwing torque will be reduced and fewer chips will be created.

(13) When assembling the dispensing end piece 14 on the reservoir 12, the internal skirt 40 is inserted into the neck 38 of the reservoir 12 and the contact with the retention zone 50 takes place after contact with the sealing zone 46. In order to illustrate the configuration of the parts to ensure this order of contact, a schematic view illustrating the relative positions of the sealing zones 46 and the chips retention zones 50 is represented in FIG. 4.

(14) The internal surface 42 of the neck 38 and the internal skirt 40 each have a theoretical length in the longitudinal direction L1=L.sub.neck theoretical sealing and L2=L.sub.end piece theoretical sealing which are intended to provide sealing, producing the sealing zone 46.

(15) The theoretical length of the neck 38 L1=L.sub.neck theoretical sealing defines, with reference to the upper end 60 of the neck 38, a minimum theoretical distance D1=D.sub.neck theoretical sealing min and a maximum theoretical distance D2=D.sub.neck theoretical sealing max.

(16) The theoretical length of the dispensing end piece 14 L2=L.sub.end piece theoretical sealing defines, with respect to the bottom of the groove 100 of the dispensing end piece 14, a minimum theoretical distance D3=D.sub.end piece theoretical sealing min and a maximum theoretical distance D4=D.sub.end piece theoretical sealing max.

(17) To ensure that there is sealing, that is to say that at least a part of the length L1=L.sub.neck theoretical sealing of the internal surface 42 of the neck 38 is in contact with at least a part of the length L2=L.sub.end piece theoretical sealing of the internal skirt 40 of the dispensing end piece 14, it is required that the following holds simultaneously: i) D1=D.sub.neck theoretical sealing min<D.sub.end piece theoretical sealing max=D4 and that ii) D3=D.sub.end piece theoretical sealing min<D.sub.neck theoretical sealing max=D2.

(18) Thus, when the end of the neck 38 and the bottom of the groove 100 of the dispensing end piece 14 are in contact, the sealing is guaranteed.

(19) Likewise, the conditions for the chips retention zone 50 to exist can be understood. The internal surface 42 of the neck 38 and the internal skirt 40 each have a theoretical length in the longitudinal direction L3=L.sub.neck theoretical retention and L4=L.sub.end piece theoretical retention which are intended to provide the retention zone, producing the chips retention zone 50.

(20) The theoretical length of the neck 38 L3=L.sub.neck theoretical retention defines, with reference to the upper end 60 of the neck 38, a minimum theoretical distance D5=D.sub.neck theoretical retention min and a maximum theoretical distance D6=D.sub.neck theoretical retention max.

(21) The theoretical length of the dispensing end piece 14 L4=L.sub.end piece theoretical retention defines, with reference to the bottom of the groove 100 of the dispensing end piece 14, a minimum theoretical distance D7=D.sub.end piece theoretical retention min and a maximum theoretical distance D8=D.sub.end piece theoretical retention max.

(22) To ensure that there is the retention zone, that is to say to ensure that at least a part of the length L3=L.sub.neck theoretical retention of the internal surface 42 of the neck 38 is in contact with at least a part of the length L4=L.sub.end piece theoretical retention of the internal skirt 40 of the dispensing end piece 14, it is required that the following holds simultaneously: iii) D5=D.sub.neck theoretical sealing min<D.sub.end piece theoretical sealing max=D8 and that iv) D7=D.sub.end piece theoretical sealing min<D.sub.neck theoretical sealing max=D6.

(23) Thus, when the end of the neck 38 and the bottom of the groove 100 of the dispensing end piece 14 are in contact, the chips retention zone 50 is guaranteed.

(24) In the following, the configurations allowing the contact of the retention zone 50 to take place after the contact of the sealing zone 46 are developed.

(25) The minimum theoretical distances on the neck D1=D.sub.neck theoretical sealing min and D5=D.sub.neck theoretical retention min define a length of the neck L5=L.sub.neck min, delimited by the upper end of the theoretical length providing sealing and the upper end of the theoretical length providing the retention zone. Moreover, the maximum theoretical distances on the end piece D4=D.sub.end piece theoretical sealing max and D8=D.sub.end piece theoretical retention max define a length of the end piece L6=L.sub.end piece max, delimited by the lower end of the theoretical length providing sealing and the lower end of the theoretical length providing the retention zone.

(26) To ensure that the contact of the retention zone 50 takes place after the contact of the sealing zone 46, it is required that the following holds: L5=L.sub.neck min>L6=L.sub.end piece max.

(27) It will be understood that a “theoretical” length denotes a predefined length on the neck of the reservoir or the dispensing end piece at the time of designing or manufacturing these parts, knowing that, due to the manufacturing tolerances, once the parts have been assembled, sealing or chips retention does not necessarily take place over the entire theoretical length, but only over a part of this length. Thus, it can be found that on the devices configured according to this embodiment the neck of the reservoir has a length L.sub.neck min delimited by the upper end of the length of the neck providing sealing L.sub.neck sealing and the upper end of the length of the neck providing the chips retention zone L.sub.neck retention, the dispensing end piece has a length L.sub.end piece max delimited by the lower end of the length of the dispensing end piece providing sealing L.sub.end piece sealing and the lower end of the length of the dispensing end piece providing the chips retention zone L.sub.end piece retention, and the device is dimensioned such that L.sub.neck min>L.sub.end piece max.

(28) As can be seen in FIG. 5, the reservoir 12 is configured such that the internal surface 42 of the neck 38 has a sealing diameter D.sub.E greater than the chips retention diameter D.sub.R.

(29) It will be noted that the neck 38 of the reservoir 12 is made, in this example, of low density polyethylene, and the internal skirt 42 of the dispensing end piece 14 is made of high density polyethylene.

(30) It will be understood that the devices 10 described above are particularly advantageous for avoiding the presence of chips in the reservoir 12 and that the invention is not limited to the examples described above.