TUBE WITH THROTTLE INSERT

Abstract

The tube (1) includes a connector (9) with a dispensing duct (13) which connects a dispensing opening (11) to a reservoir (3). For the dosed dispensing of a liquid from the reservoir (3) through the dispensing opening (11), a throttle insert (31) is inserted into a distal section (9b) of the connector (9) and is connected in form-fitting fashion to the connector (9). The connection of the throttle insert (31) to the connector (9) is preferably realized by a radial pressing action. The throttle insert (31) is preferably of dome-like form and delimits at least one primary throttle duct (47) which forms in the dispensing duct a constriction which limits the volume flow of the liquid from the reservoir (3) to the dispensing opening (11).

Claims

1. A tube (1), comprising a reservoir (3) for a fluid medium, a connector (9) with a dispensing duct (13) which connects a dispensing opening (11) to the reservoir (3), the dispensing opening (11) is arranged at a proximal section (9a) of the connector (9), and a distal section (9b) of the connector (9) is connected via a tube shoulder to a tube shell (5) which encloses the reservoir (3), a throttle insert (31) arranged in the dispensing opening (13) so as to form in the dispensing opening (13) a constriction which closes off the dispensing opening (13) aside from at least one primary throttle duct (47) in the throttle insert, the throttle insert (31) is dome-shaped and includes an outer shell surface (33) and a face-side abutment ring (39) that meet at a distal outer edge (35), and the throttle insert (31) is fastened with a form-fit in the connector (9) by the face-side abutment ring (39) which forms an undercut with a ring-shaped step (17a) on an inner wall of the connector (9).

2. The tube (1) according to claim 1, wherein the ring-shaped step (17a) is a distal end section of a ring-shaped recess (17) on the inner wall of the connector (9).

3. The tube (1) according to claim 1, wherein the connector (9) and the throttle insert (31) are manufactured from different plastics, and a material of the throttle insert (31) is harder than a material of the connector (9).

4. The tube (1) according to claim 1, wherein the outer shell surface (33) of the throttle insert (31) extends from the distal outer edge (35) to a proximal outer edge (37), and a diameter (D3a) at the distal outer edge (35) is greater than a diameter (D3b) at the proximal outer edge (37), a distal section, adjoining the distal outer edge (35) of the throttle insert (31), of the shell surface (33) bears in sealing fashion against the inner wall of the connector (9), and a proximal section, adjoining the proximal outer edge (37), of the shell surface (33) is arranged radially spaced apart from the inner wall of the connector (9), such that said inner wall and the proximal section of the shell surface (33) delimit an interposed ring-shaped chamber (19).

5. The tube (1) according to claim 1, characterized in that the primary throttle duct (47) is delimited by a channel-shaped recess on the outer shell surface (33) of the throttle insert (31) and by the inner wall of the connector (9), and the primary throttle duct (47) has a first mouth at the face-side abutment ring (39) and has a second mouth in the shell surface (33).

6. The tube (1) according to claim 5, wherein the throttle insert (31) comprises a face-side top section (50) with a central region and with a peripheral contact ring (49) projecting axially thereon, and, for the connection of the ring-shaped chamber (19) to a dispensing chamber (55) which is connected to the dispensing opening (11), at least one of: a) the contact ring (49) is arranged with a spacing (S1) to an adjacent abutment surface of the proximal section (9a) of the connector (9), or b) the contact ring (49) comprises at least one secondary throttle duct (51).

7. A throttle insert (31) for use in a tube (1), comprising: a dome-shaped body of revolution with an outer shell surface (33) and with an abutment ring (39), the shell surface (33) extends from a distal outer edge (35) with a maximum diameter (D3a) to a proximal outer edge (37) with a relatively small outer diameter (D3b), the abutment ring (39) adjoins the distal outer edge (35) at a face side, a channel-shaped recess as a delimitation for a primary throttle duct (47) is recessed in the shell surface (33), and said channel-shaped recess extends from a mouth in the abutment ring (39) to a mouth in the shell surface (33).

8. The throttle insert (31) according to claim 7, wherein the body of revolution has, adjoining an inner edge of the abutment ring (39), a ring-shaped cavity (41) which is delimited at a face side by a base plate (43) and at an inside by an installation pin (45) which projects in a distal direction from the base plate (43).

9. The throttle insert (31) according to claim 7, wherein the body of revolution comprises a face-side top section (50) with a peripheral contact ring (49) adjoining the proximal outer edge (37), the top section (50) is disk-shaped or has a pan-shaped depression (53), and at least one channel as a delimitation of a secondary throttle duct (51) is recessed in the contact ring (49).

10. A method for producing a tube (1) according to claim 1, comprising pushing the throttle insert (31) into the interior of the connector (9) from the distal side as far as a certain axial position and pressing the throttle insert together radially with the connector (9), and plastically deforming a material of the connector (9) adjacent to the throttle insert (31), creating an axial undercut of the connector (9) by the throttle insert (31).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The invention will be described in more detail below on the basis of a number of figures, in which:

[0031] FIG. 1 shows a cross section through a first tube with a first throttle insert in the region of the dispensing opening,

[0032] FIG. 2 shows a plan view of the first throttle insert,

[0033] FIG. 3 shows a cross section through the throttle insert along the line A-A in FIG. 2,

[0034] FIG. 4 shows a perspective view of the first throttle insert,

[0035] FIG. 5 shows a further perspective view of the first throttle insert,

[0036] FIG. 6 shows a cross section through a second tube with a second throttle insert in the region of the dispensing opening,

[0037] FIG. 7 shows a cross section through a third tube with a third throttle insert in the region of the dispensing opening, and

[0038] FIG. 8 shows a cross section through a fourth tube with a fourth throttle insert in the region of the dispensing opening.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] FIG. 1 shows a first embodiment of a tube 1 with a reservoir 3 for a fluid or a liquid medium, wherein the reservoir 3 is encased or enclosed by a tube shell 5. The tube shell 5 is preferably manufactured from a multi-layer laminate foil, which comprises at least one plastics layer and preferably one barrier layer composed of metal or plastic and which is shaped to form a tube. Via a tube shoulder 7, a front edge of the tube shell 5 is connected to a distal section 9b of a tubular connector 9, which forms a dispensing duct 13. At a proximal section 9a of the connector 9 there is formed a dispensing opening 11 which is connected via the dispensing duct 13 to the reservoir 3. The connector 9 and the tube shoulder 7 may be manufactured as a single injection-molded part, which, with the exception of an external thread 15 in the distal section 9b of the connector 9, is substantially rotationally symmetrical with respect to a tube axis X. In the embodiment as per FIG. 1, the proximal section 9a of the connector 9 is a ring-shaped disk, the central recess of which is the dispensing opening 11. The diameter D1 of the dispensing opening 11 is smaller than the smallest inner diameter D2a of the dispensing duct 13 in the adjoining distal section 9b of the connector 9. The ring-shaped disk thus forms an abutment surface which projects radially inwardly on the inner wall of the connector 9.

[0040] This inner wall has an angle of inclination α, which may lie for example in the range from 75° to 90°, with respect to a plane normal to the tube axis X.

[0041] A throttle insert 31, which is illustrated in more detail in FIGS. 2 to 4, is inserted into the dispensing duct 13 so as to have a small spacing S1 with respect to the ring-shaped disk or with respect to the abutment surface of the proximal section 9a of the connector 9, wherein said spacing S1 preferably lies in the range from 0 to 1 mm. The throttle insert 31 comprises substantially a dome-like or cowl-like body of revolution with an outer shell surface 33 which extends from a lower or distal outer edge 35 with a maximum diameter D3a over a height H to an upper or proximal outer edge 37 with a diameter D3b, wherein D3b is smaller than D3a. With respect to a plane normal to the axis Y of the throttle insert 31, the shell surface 33 has, at the distal outer edge 35, an angle of inclination β1 and, at the proximal outer edge 37, an angle of inclination β2, wherein β1>=β2. In between, the gradient angle of the shell surface 33 may vary in continuous or stepped fashion. Alternatively or in addition, it would also be possible for the outer diameter of the shell surface 33 to decrease in one or more steps along the height H. The outer diameter of the throttle insert 31 is smaller adjacent to the proximal outer edge 37 than at the distal outer edge 35.

[0042] It is preferably the case that the angle of inclination β1 and the outer diameter D3 at the distal outer edge 35 and in a distal section 9b, adjoining said distal outer edge, of the throttle insert 31 correspond to the angle of inclination α and the inner diameter D2 of the adjoining distal section 9b of the connector 9.

[0043] This is the case in particular if a throttle insert 31 is pressed together radially with the connector 9. During the pressing-in of the throttle insert 31, the inner wall of the connector 9 is plastically deformed and, in the distal section 9b, is adapted to the outer contour of the throttle insert 31. In this way, a ring-shaped step 17a is also formed on the inner wall of the connector 9, the outer diameter of which ring-shaped step corresponds to the maximum outer diameter D3a of the throttle insert 31. This ring-shaped step 17a may be relatively narrow, and preferably has a width which lies in the range from 0.1 mm to 0.6 mm, in particular from 0.1 mm to 0.2 mm. The ring-shaped step 17a is the lowermost section, or a distal end section, of a ring-shaped recess 17 which is caused by the distal section 9b of the throttle insert 31 during the pressing-in into the cylindrical or conical inner wall of the connector 9. During the pressing-in of the throttle insert 31 into the dispensing duct 13, said throttle insert, due to the relatively large outer diameter D3a, causes an expansion of the wall of the connector 9 and partially contracts again behind the distal outer edge 35.

[0044] At the distal outer edge 35, the throttle insert 31 comprises a face-side abutment ring 39 which adjoins the shell surface 33 and which preferably lies in a plane orthogonal to the axis Y of the throttle insert 31, or which may alternatively have an angle of inclination between 0° and approximately 60° (not illustrated). In the direction of the axis Y, radially adjacent to the inner edge of the abutment ring 39, a ring-shaped cavity 41 is recessed out of the body of the throttle insert 31. This gives rise to a material saving and a more uniform material thickness in relation to a solid body, which is advantageous for the efficient production of an injection-molded part. This is of importance in particular for the production of throttle inserts with relatively large outer diameters. Furthermore, for the pressing-in of the throttle insert 31 into the connector 9, a tool or a plunger can be inserted into the cavity 41, which tool bears against the inner wall of the throttle insert 31 and promotes the radial pressing-in of the throttle insert 31 into the inner wall of the connector 9.

[0045] A preferably cylindrical or slightly conical axial installation pin 45 projects in a distal direction on a base disk 43 which delimits the cavity 41 as a face side, said installation pin projecting preferably beyond the plane of the distal outer edge 35.

[0046] Along the periphery of the throttle insert 31, a channel-like primary throttle duct 47 is recessed into the shell surface 33, the distal end of which primary throttle duct opens out in the face-side abutment ring 39, and the proximal end of which primary throttle duct opens out in the proximal section of the shell surface 33, where the outer diameter D3 of the shell surface 33 is relatively small for the purposes of delimiting the ring-shaped chamber 19. The depth S2 of the primary throttle duct 47 and the radius R1 of the throttle insert 31 in the region of the primary throttle duct 47 are dimensioned such that, when the throttle insert 31 is inserted into the connector 9, a passage opening for the passage of liquid out of the reservoir 3 into the ring-shaped chamber 19 remains free at both ends of the primary throttle duct 47. The cross section of said passage openings may be optimized in accordance with the liquid to be dispensed and the respective design of the connector 9. Since at least the distal region of connectors 9 of various tubes is standardized, it is possible for a multiplicity of different tubes to be equipped with relatively few embodiments of the throttle insert 31. Since the throttle insert 31 is inserted, in the interior of the connector 9, into the dispensing duct 13, it is also possible in the case of such tubes to use standardized closures. At the proximal outer edge 31, a face-side top section 50 of the throttle insert 31 adjoins, by a peripheral contact ring 49, the shell surface 33. The central region of the top section 50 is of disk-like form or is in the form of a pan-like depression 53. Analogously to the primary ducts 47, one or more channels are recessed out of the contact ring 49, which channels are provided for delimiting, together with the adjoining part of the connector 9, one or more secondary throttle ducts 51 when the contact ring 49, in the proximal section 9a, bears against the inner side of the connector 9 or is in contact with said inner side. The ends of said secondary throttle ducts 51 open into the ring-shaped chamber 19 and into a dispensing chamber 55 which is connected to the dispensing opening 11 and which is delimited by the proximal section 9a of the connector 9 and by the top section 50 of the throttle insert 31. If the top section 50 has a depression 53 adjoining the contact ring 49, said depression can be used for the dosing of a certain quantity of the liquid to be dispensed. With the tube 1 held upright, it is firstly the case that, by virtue of the reservoir 3 being compressed, liquid is conveyed into the pan-like structure 53 until the latter is full. If the liquid level rises above the edge of the contact ring 49, the excess liquid can be sucked back into the reservoir 3 by a negative pressure in the reservoir 3 caused by the elastic restoring force of the tube shell 5.

[0047] As shown in FIG. 1, the throttle insert 31 can be arranged axially in the connector 9 so as not to bear directly against the proximal section 9a of the connector 9, such that a ring-shaped gap remains free between the contact ring 49 and the proximal section 9a of the connector 9. This gap connects the ring-shaped chamber 19, additionally or alternatively to the secondary throttle ducts 51, to the dispensing chamber 55. By the gap width S1 and the cross-sectional area of the one or more secondary throttle ducts 51, the flow resistance exerted by the throttle insert 31 on a particular liquid when the latter is displaced out of the reservoir 3 toward the dispensing opening 11 can be additionally influenced.

[0048] In an embodiment of the tube 1 as per FIG. 1, the external thread 15 is an M9×1.5 thread. The corresponding throttle insert 31 has a maximum outer diameter D3a of 5.5 mm and a height H of 3.2 mm. The number of primary throttle ducts 47 is 1, and the number of secondary throttle ducts 51 is 3, wherein all of the throttle ducts 47, 51 are arranged in uniformly distributed fashion, at angular intervals of 90°, on the throttle insert 31. The invention also encompasses other embodiments of the tube 1 and/or of the throttle insert 31, in which, in particular, the number, arrangement, cross sections and design of the primary throttle ducts 47 and/or of the secondary throttle ducts 51 may differ. It is preferably the case that primary throttle ducts 47 and secondary throttle ducts 51 are arranged offset with respect to one another. This promotes a further increase of the flow resistance. FIGS. 6, 7 and 8 show further embodiments of tubes 1 with throttle inserts 31.

[0049] In the case of a tube 1 as per FIG. 6, the proximal section 9a of the connector 9 comprises a slightly conical cannula 10, at the relatively narrow end of which the dispensing opening 11 is arranged, and the relatively wide end of which is connected by means of a ring-shaped flange 12 to the distal section 9b of the connector 9. In the embodiment of the tube 1 illustrated in FIG. 6, the external thread 15 is an M11×1.5 thread. The throttle insert 31 has a maximum outer diameter D3a of 7.2 mm and a height H of 3.6 mm. In relation to the embodiment of the throttle insert 31 as per FIG. 3, the contact ring 49 is wider. The diameter of the pan-like structure 53 is relatively small, and the secondary throttle ducts 51 extend radially toward the tube axis X beyond the inner edge of the ring-shaped flange 12, such that the ends that open into the dispensing chamber 55 are no longer covered by the ring-shaped flange 12.

[0050] The further tube 1 illustrated in FIG. 7 comprises an M22×1.5 external thread 15. The throttle insert 31 has a maximum outer diameter D3a of 18.3 mm and a height H of 5.3 mm. In comparison with the embodiment of the throttle insert 31 as per FIG. 3, the outer diameter D3a is considerably larger in relation to the height H. The contact ring 49 is a relatively narrow ring, the width and height of which may for example lie between 0 and 1 mm. The secondary throttle ducts 51 are correspondingly short. The pan-like structure 53 in the top section 50 comprises, adjoining the contact ring 49, an outer ring 53a or a first ring-shaped step which lies substantially at the base level of the contact ring 49. The outer ring 53a is a flange-like edge of an inner pan-like structure 53b, the base of which lies at a considerably lower level between those of the distal outer edge 35 and of the outer ring 53a. The inner edge of the outer ring 53a has a larger radius than the dispensing opening 11, such that the outer ring 53 is completely covered by the proximal section 9a of the connector 9.

[0051] In the case of the further tube 1 illustrated in FIG. 8, the proximal section 9a of the connector 9 is in the form of a ring-shaped collar adjoining the distal section 9b, the inner edge of which collar is a tube section 21 whose proximal end defines the dispensing opening 11.

[0052] The shape and size of the throttle insert 31 is coordinated with the design of the connector 9 such that the distal end region of the tube section 21 protrudes into the pan-like structure 53 or axially overlaps the edge of the pan-like structure 53 such that the inner wall of the pan-like structure 53 and the end region of the tube section 21 form a ring-shaped gap 23 which connects the ring-shaped chamber 19 to the dispensing chamber 55. The tube section 21 may be beveled at the outside, as illustrated in FIG. 8. The wall of the pan-like structure is correspondingly inclined. Alternatively or in addition to one or more secondary throttle ducts 51 arranged at a face side on the contact ring 49, these throttle ducts may also be arranged analogously on the inner wall of the pan-like structure 53. This has the advantage that, even when the inner wall of the pan-like structure 53 bears against the tube section 21, at least the free cross-sectional area of the secondary throttle ducts 51 remains free for the passage of liquid.

[0053] Coaxially with respect to the installation pin 45, a droplet pin 46 projects, on the inner side of the pan-like structure 53, into the distal end of the tube section 21. The formation of droplets of the liquid to be dispensed can be influenced by means of characteristics of the tube section 21 and of the throttle insert 31, in particular also of the droplet pin 46. Aside from geometrical characteristics, it is the case in particular that surface characteristics such as roughness and surface tension have a major influence on the nature of the droplet formation.