HOSE CONNECTOR

Abstract

A hose connection for tubes of automated analyser systems transferring mediums like liquid fluids. The invention provides A connector for a hose transferring a medium, consisting of an inner part, wherein the inner part comprises at a first end a first section comprising an opening for accommodating a hose and a second section comprising a duct arranged between an inner base of the opening for the hose and a second end of the inner part that is opposite of the first end, wherein the first section has a greater outer diameter than the second section; and an outer part, wherein the outer part comprises a thread surrounding the second section and a grip surrounding the first section, wherein the outer part is fixed rotational movable around the inner part between a flange at the inner part's second end the first section with the greater outer diameter

Claims

1. A connector for a hose transferring a medium, comprising: an inner part, wherein the inner part comprises at a first end a first section comprising an opening for accommodating a hose and a second section comprising a duct which is arranged between an inner base ground of the opening for accommodating the hose and a second end of the inner part that is opposite of the first end, wherein the first section has a greater outer diameter than the second section; and an outer part, wherein the outer part comprises a thread surrounding the second section and a grip surrounding the first section; wherein the outer part is fixed rotationally movable around the inner part.

2. The connector of claim 1, wherein the inner diameter of the opening for the hose is conically reduced towards the inner base ground of the opening for the hose.

3. The connector of claim 1, wherein the inner part is made of a transparent material.

4. The connector of claim 1, wherein the outer part's grip provides at its end adjacent to the thread a surface for accommodating a marker.

5. The connector of claim 4, wherein the surface for accommodating a marker surrounds the outer part.

6. The connector of claim 1, wherein the outer part has a ¼-28UNF thread.

7. The connector claim 1, wherein the inner part is inserted into the outer part.

8. A system comprising: a connector for a hose transferring a medium, consisting of: an inner part, wherein the inner part comprises at a first end a first section comprising an opening for accommodating a hose and a second section comprising a duct which is arranged between an inner base ground of the opening for accommodating the hose and a second end of the inner part that is opposite of the first end, wherein the first section has a greater outer diameter than the second section; and an outer part, wherein the outer part comprises a thread surrounding the second section and a grip surrounding the first section; wherein the outer part is fixed rotationally movable around the inner part.

9. The system of claim 8, wherein the inner diameter of the duct is identical to the inner diameter of the hose.

10. The system of claim 8, wherein the inner diameter of the opening for accommodating the hose is identical or smaller than the outer diameter of the hose that is accommodated in the opening.

11. The system of claim 8, wherein a hose is accommodated in the opening of the inner part with an adhesive between outer diameter of the hose and inner diameter of the opening for the hose.

12. The system of claim 8, wherein a hose with an outer diameter of up to 7 mm is accommodated in the inner part's opening for the hose.

13. The system of claim 8 further comprising: a counterpart for the connector's outer part thread having a female thread corresponding to the thread of the connector's outer part.

14. A method of using a system according to claim 8 comprising the step of connecting a hose in the connector.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0029] The invention will be described based on figures. It will be understood that the embodiments and aspects of the invention described in the figures are only examples and do not limit the protective scope of the claims in any way. The invention is defined by the claims and their equivalents. It will be understood that features of one aspect or embodiment of the invention can be combined with a feature of a different aspect or aspects of other embodiments of the invention, in which:

[0030] FIG. 1 shows hoses which are connected to a fitting according to the invention.

[0031] FIG. 2 shows which are interlocked in two-part torsional fittings.

[0032] FIG. 3 shows sectional views through two-part torsional fittings according to the invention.

[0033] FIG. 4 shows a one-part fitting with an attached flange.

[0034] FIG. 5 shows a two-part torsional fitting with an attached flange.

DETAILED DESCRIPTION OF THE INVENTION

[0035] The technical problem is solved by the independent claims. The dependent claims cover further specific embodiments of the invention.

[0036] The term inner base ground refers to an inner surface of the inner part against which the end of a hose is pressed. The inner base ground is thus the difference in diameter between the diameter of the opening for accommodating a hose in a first section of the inner part and the diameter of the duct in a second section of the inner part.

[0037] The outer part is fixed around the inner part in a manner that the outer part can be rotated around the inner part. Thus, the outer part is fixed rotationally movable around a longitudinal axis around the inner part. The outer part may be fixed between a flange located at the inner part's second end (end of second section) and a diameter transition area to the larger diameter of the first section.

[0038] The term ‘medium’ shall refer within the meaning of the present invention to a liquid, a liquid comprising solid parts like particles of any material and of biological or synthetic origin. The medium may also be gaseous comprising liquid droplets and/or solid particles.

[0039] A marker within the meaning of the present invention refers to elements that may be used to label a connector so that it can be differentiated from other connectors. A marker can be a ring or an adhesive comprising a specific color or any barcode. A RFID tag may also be a marker according to the present invention.

[0040] The present invention refers to a two-part, torsional coupled fitting within the meaning of a fitting screw for female thread (e.g. ¼-28UNF) in which thermoplastic elastomer hoses with an outer diameter of up to 7 mm can be glued without the need of additional components such as a flange that has to be attached to the hose's end to achieve tightness.

[0041] The inner part of the torsional coupled fitting generates the sealing connection between the hose and the counterpart. The hose is merely joined with a solvent adhesive cohesively into the inner part. The sealing connection results from pressing the end face of the inner part against the thread root of the counterpart.

[0042] The outer part establishes the mechanical connection between the inner part and the counterpart. Here, the inner part is anchored in the outer part. This is done by plugging together and then anchoring both components. The outer part may have a thread (e.g. ¼-28UNF) and provides the necessary mechanical contact force or pressure to the inner part and is thus responsible for the contact force or pressure of the inner part to the end face of the thread root of the counterpart. This combination of bonding techniques enables the transfer of pressures comparable to those of classic joints (e.g. ¼-28UNF).

[0043] Inner part and outer part are merely inserted into each other and thus determined along a z-axis only translational, a rotational movement about the z-axis is remaining. This results in the end in the necessary rotational decoupling between hose and screwed outer part. The hose that is cohesively connected to the inner part can be connected to the nut thread without twisting it.

[0044] The thread (e.g. ¼-28UNF) has a comparatively low pitch regarding the locking thread of a Luer lock connection. Usually, fittings with threads (e.g. ¼-28UNF) require between 5 and 9 turns to establish a reliable connection between two coupling partners. The resulting self-locking between screw and nut thread is significantly higher compared to the locking thread of the Luer lock connection. As a result, these connections remain permanently sealed even with vibrations and temperature changes.

[0045] Very thin walls can be realized in both components by using specific plastics. If the fitting is completely mounted and screwed in addition, the circumferential nut thread additionally supports the connection. This makes it possible to realize internal cross sections of up to 3.2 mm in the fitting. This means that hoses can be connected to the inner diameter of 3.2 mm within the respective fitting, without the need of significantly reducing the inner diameter and thus affecting the flow rate.

[0046] Using transparent plastics allows to inspect visually and assess the joining process between hose and inner part. Defective connections can thus be identified quite easy even before fitting the fitting parts.

[0047] The present invention allows to connect thermoplastic elastomer hoses in a very small space with other systems. The connection does not significantly reduce the cross-section of the hose line. In addition, the connection is pre-stressed via the thread (e.g. ¼-28UNF) and is therefore pressure-resistant and protected against loosening by itself.

[0048] A connection according to the present invention shall fulfill the following requirements: [0049] Pressure-resistant up to min. 8 bard [0050] Low cost structure; [0051] Simple installation; [0052] Resistant to vibration; [0053] Suitable for thermoplastic elastomers such as PVC or TPU as tubing; [0054] No or no significant reduction in cross-section flow; [0055] Connection through a thread, e.g., ¼-28UNF; [0056] Optical assignment of several hoses; and [0057] Tolerant of incorrectly executed hose cuts (angularity, surface quality).

[0058] The embodiment shown in FIG. 1 shows hoses 5 which are connected to a fitting 1 that has a thread 2. A ring 7 is arranged at the fitting as a marker enabling to distinguish different fittings/hoses transferring different liquids.

[0059] The exemplary design shown in FIG. 2 shows hoses 5 which are interlocked in two-part torsional fittings 1. The screw connection 9 is resistant against vibrational movements and pressure. The front side 11 is pressed against the thread ground 13 so that a reliable sealing results even during pressurization.

[0060] FIG. 3 shows sectional views of two different embodiments with hoses 5 having a different diameter, which are glued into the inner part 15 of a two-part torsional fitting 1 according to the invention. The inner part 15 of a two-part torsional fitting 1 can be transparent so that the gluing can be optically verified.

[0061] Outer part 25 surrounds inner part 15. The inner part 15 has a first section 16 between the opening for a hose 18 on a first end 22 of the inner part 15 and its base ground 20. The first section 16 further comprises a transition area 24 to the second section 17. The transition area 24 may also be part of the second section 17 or may be arranged between first and second section 16, 17. The first section 16 of inner part 15 is surrounded by a grip element 26 of outer part 25. Transition area 24 may be shaped conically (left part of FIG. 3) or in one step (right part FIG. 3).

[0062] The inner part 15 has further a second section 17 starting below transition area 24 of the first part 15 and a second end 23 of the inner part 15. Second section 17 of inner part 15 is surrounded by a thread 27 on outer part 25.

[0063] In both embodiments shown in FIG. 3, the inner part 15 has a flange at the second end 23. Thus, outer part 25 is fixed between first section 16 of the inner part 15, which has a larger diameter than its second section 17 and flange 21.

[0064] The sectional views in FIG. 3 show further that there is no significant reduction of the inner diameter in the transition from the hose to inner part 15 of the two-part torsional fitting 1. Thus, the flow of liquids will not be influenced or impeded.

[0065] One advantage of the invention is to provide a user-friendly connection and disconnection of hose connections made of thermoplastic elastomers. The direct bonding of the hose within the fitting eliminates the need to attach the hose. The entire composite can be screwed and tightened by hand through the thread. In case of a necessary replacement, the entire composite can be unscrewed. Peeling off the tube, which may cause injuries is eliminated.

[0066] Another advantage is the lack of mechanical stress by the torsional fitting. It is not possible to twist or torsional stress the hose during screwing due to the possibility of rotational decoupling. The hose can not exert any mechanical stress on the periphery regardless of the bending radii after screwing.

[0067] The two-part torsional fitting has no significant cross-sectional changes which may cause turbulences. The constant cross-section of the complete composite does not allow the formation of turbulences at cross-sectional changes, edges, heels, etc. This reduces interfering effects such as spontaneous outgassing or cavitation.

[0068] Another advantage of the present invention in this regard is that no significant cross-sectional reductions are present that may act as flow resistances. Any flow resistors are omitted.

[0069] A safe cohesive connection between hose and connector is a further advantage provided by the present invention. The material connection between the fitting and hose generates a connection which is not susceptible to mechanical effects, e.g. tensile forces, vibrations, pressure or the like. This makes the entire composite safe and reliable during application.

[0070] The present invention further provides a pressure resistant connection by pressing two sealing surfaces via screw connection on a counterpart. This type of pressure-resistant connection is also used in hydraulics, where only two sealing surfaces are pressed against each other. The necessary contact pressure is applied via a thread. A high gear reduction results from screwing because of the pitch of the thread. Thus, the sealing connection can be made only by hand. In addition, the selected slope prevents self-locking an independent release of the connection.

[0071] Finally, the possibility to visually inspect the adhesive bond by using transparent materials is an advantage, so that the cohesively produced compound can be verified immediately after bonding. Inclusions of air bubbles, use of too much or too little adhesive and damage to the fitting or hose will be immediately visible.

[0072] Alternative approaches to circumvent or realize the present invention encompass the use of currently used fluoropolymer hoses, which have the above mentioned advantages of rotational decoupling, constant flow cross-section, pressure stability etc.

[0073] The flange 21 may also be fixed to a one part fitting 1a as a separate component (FIG. 4). One possibility to fix such a flange 21 can be to glue it to hose 5. The above described methods for reshaping the end of the hose or applying an additional part to a hose's end to generate a sealing effect between fitting screw, hose and counterpart relate mostly refer to fluoropolymers. Thus, materials which can not just be plugged because of their low surface energy, their creep behavior, their high hardness or their pressure resistance. Pressure-resistant hoses may also be made of materials with a higher surface energy, so that materials can be added by cohesive methods such as gluing them. Thermoplastic polyurethanes (TPU) belong to the thermoplastic elastomers, which can be treated with a suitable solvent. A flange 21 made of an appropriate material may be treated in the same way e.g. the inner surface may be dissolved with a solvent, so that both part can be connected or cold welded.

[0074] Thus, it will be possible with such an approach to apply cohesively a flange 21 made of TPU on the front side of the hose 5 made of TPU. In this case, the reshaping of the hose's end or inserting an additional part into it will be eliminated. However, it will also be required that an additional decoupling ring 30 is added for decoupling torsional forces between the fitting 1a and flange 21 when tightening the composite.

[0075] The other possibility is to glue the hose 5 into the inner part 15 of the two-part torsional fitting 1, similar to the method described above. Flange 21 shown in FIG. 4 forms an undercut. Thus, the inner and outer parts (15, 25) can be mounted together only by a deformation of the outer part. This is realized over a defined elastic range of both components so that they are locked together. Alternatively, the flange 21 can be made separately. Thus, it will be possible to first insert the outer and inner parts (15, 25) into each other. Subsequently, flange 21 is glued to the front side of the inner part and thus fixes the inner and outer parts to each other (FIG. 5).

[0076] A further approach is that the inner part and hose can be connected directly in the injection molding tool instead of gluing them. The hose is inserted in the tool and overmoulded with the plastic.

[0077] The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiment was chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents. The entirety of each of the aforementioned documents is incorporated by reference herein.

REFERENCE NUMERALS

[0078] 1 two-part torsional fitting [0079] 1a one part fitting [0080] 2 thread [0081] 5 hose [0082] 7 ring [0083] 9 screw connection [0084] 11 front side [0085] 13 thread ground [0086] 15 inner part [0087] 16 first section [0088] 17 second section [0089] 18 opening for hose [0090] 19 duct [0091] 20 base ground [0092] 21 flange [0093] 22 first end [0094] 23 second end [0095] 24 diameter transition area [0096] 25 outer part [0097] 26 grip element [0098] 27 thread [0099] 30 decoupling ring