Threaded attachment for a medical hollow body, and medical hollow body having such a threaded attachment
The threaded attachment with detent and counter-detent structures addresses the issue of relative rotation in medical hollow bodies, ensuring a secure and aesthetically pleasing connection by stabilizing the design and simplifying assembly.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- VETTER PHARMA FERTIGUNG
- Filing Date
- 2026-01-15
- Publication Date
- 2026-07-23
AI Technical Summary
Existing threaded attachments for medical hollow bodies suffer from relative rotation between parts, leading to a less secure and aesthetically pleasing connection, and often require a proximal skirt or other connecting structure, which complicates design and assembly.
A threaded attachment comprising a threaded part and a retaining part with detent and counter-detent structures that prevent relative rotation, allowing a single-unit distal section and thinner design, with a retaining element that stabilizes the attachment and simplifies assembly.
The solution provides a secure, high-quality, and aesthetically pleasing connection by preventing rotation between parts, enabling a slimmer design and easier assembly, while maintaining structural stability.
Smart Images
Figure EP2026050968_23072026_PF_FP_ABST
Abstract
Description
[0001] 2024-03
[0002] 1
[0003] Veter Pharma-Fertigung GmbH & Co. KG
[0004] DESCRIPTION
[0005] Threaded attachment for a medical hollow body and medical hollow bodies with such a threaded attachment
[0006] The invention relates to a threaded attachment for a medical hollow body and a medical hollow body with such a threaded attachment.
[0007] EP 2680908 Al discloses a closure cap for a medical device, comprising a proximal part designed as a one-piece threaded attachment and a distal part, the distal part having a sealing element. The distal part also has a proximal skirt connected to a base body of the distal part via predetermined breaking points, by which it is fitted over the proximal part. In the secured state, it is held on the distal part by a detent projection located on the proximal skirt. In this way, the base body of the distal part can be separated from the proximal part and the proximal skirt by breaking the predetermined breaking points, in order to open and use the medical device, with the proximal part remaining on the medical device.The distal part can rotate relative to the proximal part when assembled, which may reduce the user's feeling of a secure and tight connection, particularly from a psychological perspective.
[0008] The invention is therefore based on the objective of creating a threaded attachment for a medical hollow body and a medical hollow body with such a threaded attachment, wherein the aforementioned disadvantages are at least reduced, preferably avoided.
[0009] The problem is solved by providing the present technical teaching, in particular the teaching of the independent claims as well as the embodiments disclosed in the dependent claims and the description.
[0010] The problem is solved in particular by creating a threaded attachment for a medical hollow body, which has a threaded part and a retaining part, wherein the 212348 PCT - KO2024-03
[0011] 2
[0012] The threaded part has a connecting thread, the retaining part has a central coupling recess for mounting the retaining part on the medical hollow body and is designed to be attached to the threaded part, the threaded part having a first number of detent structures arranged offset from one another along a circumferential direction, the retaining part having a second number of counter-detent structures arranged offset from one another along a circumferential direction, and the detent structures and the counter-detent structures being matched to each other in such a way as to work together to prevent relative rotation between the threaded part and the retaining part when the retaining part is attached to the threaded part.By designing the threaded attachment in multiple parts, including the threaded section and the retaining section, and by allowing the threaded section to be attached to the medical hollow body not directly but indirectly via the retaining section, a proximal skirt or other connecting structure between a distal section and the threaded attachment is no longer required. This makes it possible to form any distal section as a single unit with the threaded section. Furthermore, the interacting locking and counter-locking structures advantageously prevent rotation between the retaining section and the threaded section—and thus, optionally, also between the retaining section and the distal section, which is advantageously formed as a single unit with the threaded section. This significantly contributes to an improved, high-quality, and secure appearance of the threaded attachment and of a medical hollow body equipped with the threaded attachment.Furthermore, the threaded insert can be single-walled in the threaded section – instead of double-walled as in the prior art – which allows for a slimmer design and thus an even more aesthetically pleasing appearance. Finally, the retaining element advantageously stabilizes the threaded section, so that the latter can be designed with even thinner walls and thus also more aesthetically pleasing.
[0013] In the context of this technical teaching, the circumferential direction is understood to be a direction that concentrically encompasses a longitudinal axis of the threaded insert. The longitudinal axis is, in particular, the imaginary axis of rotation of the connecting thread.
[0014] The retaining element is preferably rotationally symmetrical with respect to rotation about an axis perpendicular to the longitudinal axis of the threaded insert, particularly with the cyclic group C2, i.e., with rotation by 180° (at a full angle of 360°) or 71° (at a full angle of 2°). Advantageously, the retaining element can therefore also be used with reversed top and bottom surfaces, or it is irrelevant which side of the retaining element 212348 PCT - KO2024-03
[0015] 3
[0016] facing the threaded part. This increases functional reliability and simultaneously simplifies the mounting of the retaining part to the threaded part.
[0017] In the context of this technical teaching, a connection thread is understood in particular to be a thread which serves to connect the threaded part to a medical device - or to connect a medical device to the threaded part - for example, to connect an injection needle, in particular a cannula or an injection tube.
[0018] In one embodiment, the connection thread is designed as a Luer thread.
[0019] The coupling recess is preferably designed as an axial through-opening of the retaining part and is particularly configured to allow passage through a distal area of the medical hollow body in the assembled state, in particular a Luer cone of the medical hollow body designed as a syringe.
[0020] The first number can be one, so that in this case the threaded attachment only has one locking structure; in this respect, the plural used below for the locking structures is to be understood as a generic term in view of this design and not as an indication of an actual plurality of locking structures.
[0021] In one embodiment, the first number is at least two. In another embodiment, the first number is exactly two. However, the first number can also be more than two.
[0022] Alternatively or additionally, the second number is one, so that in this case the threaded attachment only has one counter-locking structure; in this respect, the plural used below for the counter-locking structures is to be understood as a generic term in view of this design and not as an indication of an actual plurality of counter-locking structures.
[0023] In one embodiment, the second number is at least two. In another embodiment, the second number is exactly two. However, the second number can also be more than two.
[0024] 212348 PCT - KO2024-03
[0025] 4
[0026] Preferably, the second number is equal to the first. In particular, the threaded insert has as many counter-engagement structures as engagement structures. Preferably, each engagement structure is assigned a counter-engagement structure – and vice versa.
[0027] In particular, to arrange the threaded attachment on the medical hollow body, the retaining part is first connected to the threaded part, and then the threaded attachment thus assembled or mounted is placed on the medical hollow body.
[0028] In one embodiment, the retaining part is at least partially encompassed by the threaded part, particularly in the circumferential direction. In particular, the retaining part is completely encompassed by the threaded part, except for angular sections in which the counter-locking structures are arranged, particularly in the circumferential direction.
[0029] In one embodiment, the retaining part is disc-shaped, i.e., as a disk, and in particular as an annular shape, i.e., as a ring, with the coupling recess at its center. In particular, the threaded part is hollow cylindrical, i.e., as a hollow cylinder. In particular, the hollow cylinder has a shell wall that encompasses the longitudinal axis. It is possible that the hollow cylinder is closed at one end.
[0030] According to a further development of the invention, the locking structures and the counter-locking structures are arranged offset from each other by a predetermined angle along the circumferential direction. This advantageously results in a particularly uniform or symmetrical introduction of any torque into the locking structures and counter-locking structures, thus ensuring high stability. In particular, the locking structures are arranged offset from each other by the predetermined angle. Additionally, the counter-locking structures are arranged offset from each other by the same predetermined angle. Furthermore, the locking structures and the counter-locking structures are preferably arranged with equal angular spacing along the circumferential direction, i.e., at equal angular intervals from each other.
[0031] Optionally, the definite angle is 180° – for a full 360° angle – where in this case the first and second numbers are each exactly two. More generally, the definite angle is preferably 360° / ", with the first number / / , which is preferably equal to the second number.
[0032] 212348 PCT - KO2024-03
[0033] 5
[0034] According to a further development of the invention, the locking structures are designed as radial engagement recesses and the counter-locking structures as radial projections, wherein the projections engage in the engagement recesses when the retaining part is attached to the threaded part. This advantageously represents a design that is both simple and functionally reliable.
[0035] In one embodiment, the locking structures are designed as radial through-openings - or in other words, windows.
[0036] According to a further development of the invention, the locking structures and the counter-locking structures have lateral undercuts that are aligned with each other. Advantageously, the locking structures are thus particularly firmly connected to the counter-locking structures in the assembled state.
[0037] In one embodiment, the locking structures are permanently connected to the mating locking structures. This means, in particular, that the locking structures cannot be separated from the mating locking structures without destroying at least one locking structure, at least one mating locking structure, the threaded part, and / or the retaining part. Preferably, the lateral undercuts are designed and aligned such that the locking structures are permanently connected to the mating locking structures.
[0038] According to a further development of the invention, the threaded part has, in addition to the connecting thread, a retaining thread, wherein the retaining part has a mating retaining thread, and wherein the retaining thread and the mating retaining thread are matched to each other such that the retaining part can be screwed into the threaded part to mechanically connect the retaining part to the threaded part. The mating retaining thread and the retaining thread mesh with each other. Advantageously, the retaining part can be connected to the threaded part in this way particularly easily and with equal stability.
[0039] In one embodiment, the retaining thread and, correspondingly, the mating retaining thread are designed as multi-start threads, preferably as double-start threads. In particular, this allows the retaining element to be rotationally symmetrical about a rotation about the axis perpendicular to the longitudinal axis of the threaded insert, especially with the cyclic group C.
[0040] 212348 PCT - KO2024-03
[0041] 6
[0042] In one embodiment, the retaining part has at least one radial orientation structure, in particular at least one radial orientation recess, which is designed to ensure a correctly oriented, automated feeding of the retaining part to the threaded part and assembly of the retaining part on the threaded part in the production process.
[0043] According to a further development of the invention, the locking structures and the counter-locking structures are inclined with a thread pitch corresponding to that of the retaining thread. Advantageously, this allows the counter-locking structures to be inserted into the locking structures particularly easily when the retaining part is screwed into the threaded part. Furthermore, a greater overlap between the locking structures and the counter-locking structures is possible.
[0044] In the context of the present technical teaching, the fact that the locking structures and the counter-locking structures are inclined means in particular that they are set relative to the longitudinal axis of the threaded attachment, i.e., they enclose a finite angle with the longitudinal axis other than 0° and 180°.
[0045] According to a further development of the invention, the retaining thread and the connecting thread have identical thread pitches. Advantageously, this allows for particularly simple and efficient manufacturing of the threaded part, especially easy demolding in an injection molding process.
[0046] In particular, the retaining thread and the connecting thread are arranged in the correct phase with each other. A molded part used, for example, in injection molding to form the threaded inner contour of the threaded component can therefore be demolded particularly easily by unscrewing it.
[0047] According to a further development of the invention, the retaining thread has a threaded recess preceding each of the locking structures. This also advantageously facilitates the insertion, and in particular the screwing in, of the counter-locking structures into the locking structures.
[0048] 212348 PCT - KO2024-03
[0049] 7
[0050] In the context of this technical teaching, a thread recess is understood in particular to be a radial widening of the thread, i.e. a radial indentation in the thread.
[0051] The fact that the threaded recess is arranged preceding the detent structures means, in the context of this technical teaching, in particular that the threaded recess is positioned in front of its associated detent structure in the direction of rotation. Thus, when the screw is turned in, the corresponding counter-detent structure first reaches the threaded recess and then the detent structure.
[0052] In one embodiment, the respective thread recess is directly adjacent to its associated locking structure.
[0053] According to a further development of the invention, at least one axial stop for the retaining element is formed on the connecting thread. Advantageously, this provides a defined stop for the retaining element within the threaded section. Furthermore, the axial stop advantageously serves to absorb axial compressive and / or tensile forces, particularly when placing the retaining element on and / or removing it from the medical hollow body, thus ensuring that the threaded attachment is very stable overall.
[0054] According to a further development of the invention, the threaded attachment is designed as a closure cap for the medical hollow body, and the threaded part is designed as the proximal part of the closure cap, which comprises the proximal part and a distal part. This represents a particularly advantageous embodiment of the threaded attachment.
[0055] In particular, the threaded part is formed as a single piece, forming the proximal part. Alternatively or additionally, the proximal part is connected to the distal part via predetermined breaking points. Preferably, the proximal and distal parts are formed as a single piece – optionally of the same material – for example, manufactured in one piece using an injection molding process.
[0056] According to a further development of the invention, a sealing element is arranged inside the closure cap, particularly at least substantially in the distal part. Advantageously, the medical hollow body can be tightly sealed by means of the sealing element.
[0057] 212348 PCT - KO2024-03
[0058] 8
[0059] The sealing element can protrude from the distal part into the threaded part in certain areas.
[0060] Preferably, the sealing element is formed in multiple parts with the distal part, in particular inserted into the distal part.
[0061] In one embodiment, the sealing element is held in the distal part - preferably by means of positive locking elements.
[0062] The problem is also solved by creating a medical hollow body that has a threaded attachment according to the invention or a threaded attachment according to one or more of the embodiments described above. In connection with the medical hollow body, the advantages are particularly those already described in connection with the threaded attachment.
[0063] In particular, the threaded attachment with the retaining element is placed on the medical hollow body, preferably held on the medical hollow body. In one embodiment, the retaining element is placed on a projection of the medical hollow body, which is particularly conical and extends through the central coupling recess of the retaining element. The projection of the medical hollow body is thus arranged particularly centrally in the and coaxial connection thread.
[0064] In one embodiment, the projection of the hollow body is designed as a Luer cone.
[0065] According to a further development of the invention, the medical hollow body is designed as a syringe. In this embodiment, the advantages already mentioned are realized in a particularly effective way.
[0066] The invention will be explained in more detail below with reference to the drawing. The drawing shows:
[0067] Figure 1 shows a schematic representation of an embodiment of a medical hollow body with an embodiment of a threaded attachment;
[0068] Figure 2 shows a longitudinal section view of the threaded attachment according to Fig. 1;
[0069] Figure 3 shows a cross-sectional view of the threaded attachment according to Fig. 1;
[0070] Figure 4 shows a detailed view of the threaded attachment according to Fig. 1 in longitudinal section, and
[0071] 212348 PCT - KO2024-03
[0072] 9
[0073] Figure 5 shows two embodiments of a retaining part for the threaded attachment.
[0074] Fig. 1 shows a schematic representation of an embodiment of a medical hollow body 1, which here is designed as a syringe 3, with an embodiment of a threaded attachment 5.
[0075] The threaded attachment 5 is placed on and held on the medical hollow body 1 by a retaining part 11. The retaining part 11 is preferably placed on a conical projection of the medical hollow body 1 (not shown here), in particular a Luer cone, the Luer cone passing through a central coupling recess 13 of the retaining part 11 as shown in Figure 2.
[0076] The threaded attachment 5 has, in addition to the retaining part 11, a threaded part 9. The retaining part 11 is designed to be attached to the threaded part 9.
[0077] The threaded attachment 5 is preferably designed as a closure cap 35 for the medical hollow body 1, and the threaded part 9 forms a proximal part 37 of the closure cap 35, which also has a distal part 39. The proximal part 37 is preferably connected to the distal part 39 via predetermined breaking points. Preferably, the proximal part 37 and the distal part 39 are formed in one piece – preferably of the same material – for example, manufactured in one piece using an injection molding process.
[0078] Fig. 2 shows a longitudinal section view of the threaded attachment 5 according to Fig. 1.
[0079] Identical and functionally equivalent elements are provided with the same reference symbols in all figures, so that reference is made to the preceding description in each case.
[0080] The threaded part 9 has a connecting thread 7, preferably designed as a Luer thread, and, in the embodiment shown here, two locking structures 15 arranged offset from one another along a circumferential direction encompassing a longitudinal axis L of the threaded insert 5. The retaining part 11 correspondingly has two counter-locking structures 17 arranged offset from one another along the circumferential direction. The locking structures 15 and the counter-locking structures 17 are coordinated such that they interact to
[0081] 212348 PCT - KO2024-03
[0082] 10
[0083] to prevent a relative rotation between the threaded part 9 and the retaining part 11 when the retaining part 11 is attached to the threaded part 9.
[0084] The threaded part 9 is attached to the medical hollow body 1 via the retaining part 11. By means of the interacting locking structures 15 and counter-locking structures 17, rotation between the retaining part 11 and the threaded part 9 – and thus also between the retaining part 11 and the distal part 39, which is advantageously formed in one piece with the threaded part 9 – is prevented.
[0085] The coupling recess 13 is preferably designed as an axial through-opening of the retaining part 11.
[0086] In particular, to arrange the threaded attachment 5 on the medical hollow body 1, the retaining part 11 is first connected to the threaded part 9, and then the threaded attachment 5 assembled in this way is placed on the medical hollow body 1.
[0087] The grid structures 15 and the counter-grid structures 17 are each arranged offset from each other by a predetermined angle - here 180° - along the circumferential direction.
[0088] Furthermore, the locking structures 15 are designed as radial engagement recesses 21, in particular as radial through-openings or windows, and the counter-locking structures 17 as radial projections 23, wherein the radial projections 23 engage in the engagement recesses 21 when the retaining part 11 is attached to the threaded part 9.
[0089] A sealing element 41 is preferably arranged in the interior of the closure cap 35, particularly at least substantially in the distal part 39. The sealing element 41 projects partially out of the distal part 39 into the proximal part 37, i.e., into the threaded part 9.
[0090] Preferably, the sealing element 41 is formed in multiple parts with the distal part 39, and is in particular inserted into the distal part 39. Preferably, the sealing element 41 is held in the distal part 41, in particular by positive locking elements, for example, those formed as threads.
[0091] 212348 PCT - KO2024-03
[0092] 11
[0093] Fig. 3 shows a cross-sectional view of the threaded attachment 5 according to Fig. 1, in particular at approximately the level of the locking structures 15.
[0094] Figure 3 shows that the locking structures 15 and the counter-locking structures 17 have aligned lateral undercuts 25. Preferably, the locking structures 15 are connected to the counter-locking structures 17 in this way particularly firmly, preferably permanently, in the assembled state.
[0095] Fig. 4 shows a detailed view of the threaded attachment 5 according to Fig. 1 in longitudinal section.
[0096] Preferably, the threaded part 9 has – in addition to the connecting thread 7 – a double-start retaining thread 27. The retaining part 11 also has a double-start mating retaining thread 29 (see Figure 5), and the retaining thread 27 and the mating retaining thread 29 are matched such that the retaining part 11 can be screwed into the retaining thread 27 of the threaded part 9 with the mating retaining thread 29 in order to mechanically connect the retaining part 11 to the threaded part 9.
[0097] Preferably, the retaining thread 27 and the connecting thread 7 have identical thread pitches and are also arranged in phase with each other.
[0098] The retaining thread 27 preferably has a thread recess 31 preceding the locking structures 15, in particular directly adjacent to the locking structure 15 to which it is associated.
[0099] Preferably at least one axial stop 33 for the retaining part 11 is formed on the connecting thread 27, which can in particular absorb axial compressive and / or tensile forces.
[0100] Fig. 5 shows a representation of two embodiments of the retaining part 11.
[0101] In a) an embodiment of the retaining part 11 with a hexagonal coupling recess 13 - with rounded corners - is shown, in particular the embodiment also shown in Figure 3.
[0102] 212348 PCT - KO2024-03
[0103] 12
[0104] Figure b) shows an embodiment of the retaining part 11 with a more complexly shaped coupling recess 13, which has six rounded contact surfaces 42, of which only one is provided with a reference numeral for the sake of clarity.
[0105] The counter-holding thread 29 and the counter-locking structures 17 are clearly visible.
[0106] Furthermore, it is shown that the counter-locking structures 17 - and incidentally also the locking structures 15, see Figure 1 - are inclined with a thread pitch of the retaining thread 27, that is, are set at an angle to the longitudinal axis L.
[0107] The retaining part 11 also preferably has at least one radial orientation structure 43, here two radial orientation structures 43, namely in particular a radial orientation recess 45 and an orientation flattening 47, which are designed to ensure in the production process a positionally correct, automated feeding of the retaining part 11 to the threaded part 9 and a positionally correct, automated assembly of the retaining part 11 on the threaded part 9.
[0108] 212348 PCT-KO
Claims
2024-03 13 REQUIREMENTS 1. Threaded attachment (5) for a medical hollow body (1), comprising a threaded part (9) having a connecting thread (7) and a retaining part (11), wherein the retaining part (11) has a central coupling recess (13) for mounting the retaining part (11) on the medical hollow body (1) and is designed to be attached to the threaded part (9), wherein the threaded part (9) has a first number of detent structures (15) arranged offset from one another along a circumferential direction, wherein the retaining part (11) has a second number of counter-detent structures (17) arranged offset from one another along a circumferential direction, and wherein the detent structures (15) and the counter-detent structures (17) are aligned such that they interact to prevent relative rotation between the threaded part (9) and the retaining part (11) when the retaining part (11) is attached to the threaded part (9).
2. Threaded attachment (5) according to claim 1, wherein the locking structures (15) and the counter-locking structures (17) are each arranged offset from each other by a predetermined angle, optionally by 180°, along the circumferential direction.
3. Threaded attachment (5) according to one of the preceding claims, wherein the locking structures (15) are designed as radial engagement recesses (21), in particular as radial through-openings, and the counter-locking structures (17) are designed as radial projections (23), wherein the projections (23) engage in the engagement recesses (21) when the retaining part (11) is attached to the threaded part (9).
4. Threaded attachment (5) according to one of the preceding claims, wherein the locking structures (15) and the counter-locking structures (17) have matched lateral undercuts (25).
5. Threaded attachment (5) according to one of the preceding claims, wherein the threaded part (9) has a retaining thread (27), wherein the retaining part (11) has a counter-retaining thread (29), and wherein the retaining thread (27) and the counter-retaining thread (29) are matched to each other in such a way that the retaining part (11) can be screwed into the threaded part (9) in order to mechanically connect the retaining part (11) to the threaded part (9). 212348 PCT - KO2024-03 14 6. Threaded attachment (5) according to claim 5, wherein the locking structures (15) and the counter-locking structures (17) are inclined with a thread pitch of the retaining thread (27).
7. Threaded attachment (5) according to one of claims 5 or 6, wherein the retaining thread (27) and the connecting thread (7) have identical thread pitches.
8. Threaded attachment (5) according to one of claims 5 to 7, wherein the retaining thread (27) has a threaded recess (31) preceding each of the locking structures (15).
9. Threaded attachment (5) according to one of the preceding claims, wherein at least one axial stop (33) for the retaining part (11) is formed on the connecting thread (7).
10. Threaded attachment (5) according to one of the preceding claims, wherein the threaded attachment (5) is designed as a closure cap (35) for the medical hollow body (1) and the threaded part (9) is designed as a proximal part (37) of the closure cap (35) comprising the proximal part (37) and a distal part (39).
11. Threaded attachment (5) according to claim 10, wherein a sealing element (41) is arranged in an interior of the closure cap (35), which is optionally held in the distal part (39).
12. Medical hollow body (1), with a threaded attachment (5) according to one of the preceding claims.
13. Medical hollow body (1) according to claim 12, wherein the medical hollow body (1) is designed as a syringe (3). 212348 PCT - KO