The invention relates to a clamping device for fluidically and mechanically connecting two hose barbs.
Single-use systems in the field of “separations” and “fluid management” are mostly used to transport liquids and gases. Components such as filters, sensors, and actuators are connected to each other via hoses, which are often made of silicone. In order to create a tight connection, one end of the hose is pulled over the hose barb of the one component and the other end of the hose is pulled over the hose barb of the other component. The hose ends are fastened with cable ties or clamps, for example.
In particular for systems used in chromatography, filtration, and virus inactivation, it is desired to keep the volume of the hoses and components as small as possible in order to avoid a large amount of valuable medium remaining in the system at the end of the process. This is especially important when only a limited amount of medium is available and/or when the medium is of high monetary value.
One option is to rinse the system after the end of a process. However, this leads to a dilution of the processed medium such that it cannot be used for further processes.
In order to design components with the smallest possible volume, it is advantageous to bundle components in individual assemblies. This also minimizes the tube length between the components. However, a minimum tube length is usually required in order to assemble the components properly.
It is an object of the invention to simplify the assembly and to minimize the volume of systems where fluid is transported from one component to another.
The above problem is solved by a clamping device for fluidically and mechanically connecting two hose barbs. The clamping device comprises a seal and a locking mechanism, wherein the locking mechanism can be transferred from a mounting condition to an assembled condition. In the mounting condition, the hose barbs can be inserted into the clamping device, whereas in the assembled condition, these hose barbs are locked in place in a position in which free ends of the hose barbs face each other and the seal coaxially aligns and fluid-tightly connects the free ends.
The invention is based on the finding that components usually comprise hose barbs for establishing fluid connections to other components. The clamping device according to the invention makes it possible to directly connect two hose barbs, so that no hose is required. Thus, the invention not only minimizes the process volume but also the overall volume of the system. This also means that tubing material is saved. Furthermore, the assembly is simplified and more secure, since the clamping mechanism aligns the hose barbs and no tube needs to be connected with cable ties or clamps anymore.
To further increase the stability of the overall system, the locking mechanism can comprise a fixture for attaching the locking mechanism to a retaining plate.
According to a preferred embodiment of the invention, the seal and the locking mechanism are a prefabricated unit. Preferably, the seal is molded directly into the locking mechanisms. This means that the clamping device only comprises one part, which in turn further simplifies the assembly.
Preferably, the seal consists of a material resistant to irradiation and chemicals, like EPDM rubber, silicon, or a thermoplastic elastomer. These materials are suitable single-use materials which provide a sufficient chemical, temperature and irradiation stability when sterilized by heat, chemicals or radiation.
According to a preferred embodiment of the invention, the locking mechanism is preloaded into the assembled condition, such that a secure connection is ensured. Furthermore, having the locking mechanism preloaded into the assembled condition simplifies the assembly by automatically transferring the locking mechanism from the mounting condition into the assembled condition.
In order to connect two hose barbs having different dimensions, the seal and the locking mechanism can form an adapter. The adapter is especially useful for connecting hose barbs having different inner diameters since it is provided to align the hose barbs coaxially. Furthermore, having the seal and the locking mechanism form an adapter reduces the amount of parts needed to form a fluidic and mechanical connection, which helps with reducing the volume and costs.
For hose barbs having strongly differing inner diameters, the seal and the locking mechanism may comprise an intermediate section, which gradually adapts to the change in dimensions. In that case, the sealing function can be performed in two places, namely between the first hose barb and the intermediate area and between the second hose barb and the intermediate area. While this might slightly increase the system volume compared to a system, where two hose barbs with the same dimensions are connected, it ensures that the connection is possible at all and still compact and fluid-tight.
According to a first concept of the invention, the transfer of the locking mechanism from the mounting condition to the assembled condition is irreversible.
According to an alternative second concept of the invention, the locking mechanism can be reversibly transferred between the mounting condition and the assembled condition. A reversible locking mechanism allows a better waste management and makes more recycling options available since the parts can be disassembled more easily.
While the invention mainly relates to single-use systems, having a locking mechanism that can be reversibly transferred between the mounting and the assembled condition can still be an advantage, since that means that the locking mechanism can be used in multiple systems. In other words, once a process is finished, the locking mechanism can be transferred back into its mounting condition, allowing to disassemble the different components and then be used to assemble another set of components for a different process.
According to an embodiment of the invention, the seal is a sleeve with an inner wall adapted to frusto-conical shapes of the free ends of the hose barbs facing each other. This is a rather simple design, which leads to low production costs and, hence, reduces the overall costs involved.
According to another embodiment of the invention, the seal comprises a primary sealing lip for engaging an outer surface of the free ends of the hose barbs and a secondary sealing lip for engaging an inner surface of the free ends of the hose barbs. The primary and secondary sealing lips are connected by a web and form a flexure bearing. In other words, the primary sealing lip is intended to fully seal the hose barbs, while the secondary sealing lip, together with the primary sealing lip, is intended to align the hose barbs coaxially with one another. In order to protect the flexure bearing, it is possible to place rings between the frontal surface of the hose barbs and the flexure bearing.
According to yet another embodiment of the invention, the seal comprises an axial sealing piece and two guide pieces for increasing the free end surfaces of the hose barbs. The axial sealing piece is placed centrally between the two guide pieces and is preferably an O-ring. While the guide pieces are made of hard plastic, the axial sealing piece can be compressed in the assembled condition by the hose barbs.
In order for any of the seals to be functional, they need to be used in combination with a locking mechanism. One such locking mechanism according to the invention comprises a ring element encompassing the seal. Further, the ring element has latching hooks on opposite sides and two external threads. The locking mechanism also comprises two nuts having inner wall sections adapted to frusto-conical shapes of the free ends of the hose barbs and internal threads, so that the nuts can be screwed onto the ring element. Thereby, the latching hooks are forced to engage behind the rear gripping edge surfaces of the hose barbs such that the free ends of the hose barbs are pressed against each other. By using threads, it is ensured that the clamping device can be disassembled as easily as it can be assembled.
According to another embodiment of the invention, the locking mechanism comprises a first sleeve element and a second sleeve element inserted, preferably screwed, into the first sleeve element. Those sleeve elements surround the free ends of the hose barbs facing each other and are held in place in the assembled condition via a squeeze mechanism. The squeeze mechanism preferably includes radially movable slide elements, which engage behind rear gripping edge surfaces of the hose barbs in the assembled condition and have a keyhole contour adapted to the outer diameter of the hose barbs behind the gripping edges. This locking mechanism allows for an easy assembly since only the sliding elements need to be pushed into the correct position to fully secure the hose barb connection.
According to another embodiment of the invention, the locking mechanism comprises two axially spring-loaded snap rings for engaging behind rear gripping edge surfaces of the hose barbs. The snap rings are held in place by a sleeve. This particular locking mechanism allows for a very simplified assembly, since the hose barbs only have to be inserted into the sleeve. The actual transition into the assembled state is provided by the spring-loaded snap rings, which are preloaded into the assembled condition. Preferably, the axially preload force for the snap rings is given by elastomer springs or wave springs. Alternatively, the locking mechanism can also comprise a flexible O-ring between these spring-loaded snap rings and the sleeve.
According to an embodiment of the invention, the locking mechanism comprises a double-sided flexure bearing forming a clamp, which automatically opens when the hose barbs are inserted and engages behind rear gripping edge surfaces of the hose barbs once the hose barbs are fully inserted. Again, this locking mechanism consists of only one part, which simplifies the assembly. Furthermore, this locking mechanism is especially suitable to be part of a free pre-fabricated unit together with a seal.
It is to be noted that each seal can be used in combination with any one of the locking mechanisms. Further, any of the seals is only functional in combination with one of the locking mechanisms while any of the locking mechanisms requires a seal to be functional.
Further features and advantages of the invention will become apparent from the following description and from the accompanying drawings to which reference is made. In the schematic drawings:
The hose barb 10 is generally mounted to a component and generally used for fluid connection with another component. In particular, it will be described how two hose barbs 10 facing each other can be connected via a clamping device 8.
Alternatively, a seal 20 comprising a primary sealing lip 26 and a secondary sealing lip 26, as shown in
The primary sealing lip 26 fully seals the hose barbs 10 from the outside. The secondary sealing lip 28 on the other hand, is intended to align the hose barbs 10 coaxially with each other, together with the primary sealing lip 26.
Since the free ends 14 of the hose barbs 10 are pressing against the web 30 in an assembled condition, it is possible to place rings 32 between the free ends 14 and the web 30. That way the risk of damage caused by the hose barbs 10 pressing against the web 30 is reduced.
A further embodiment of the seal 20 is shown in
The ends of the guide pieces 36 facing away from the respective hose barbs 10 allow the O-ring to be centrally located in a groove 38 formed by the two guide pieces 36. The guide pieces 36 can be made of a hard plastic, while the O-ring 34 consists of a compressible material.
All of the three seals 20 described above are only functional in combination with one of the locking mechanisms 40 depicted in
A first embodiment of the locking mechanism 40 shown in
In a second step, the nuts 48 are screwed onto the ring element 42, which forces the latching hooks 44 to engage with the gripping edges 18 of the hose barbs 10. Consequently, the free ends 14 of the hose barbs 10 are pressed against each other. Furthermore, the sleeve 22 is pressed against the free ends 14 of the hose barbs 10 from three directions ensuring a fluid-tight seal. This assembled condition is shown in
An alternative locking mechanism 40 is shown in
The first and second sleeve elements 52, 54 surround the free ends 14 of the hose barbs 10 as well as the seal 20.
In order to ensure that the sleeve elements 52, 54 do not move with respect to each other, they can be screwed together via an internal thread of the first sleeve element 52 and an external thread of the second sleeve element 54. For the sake of simplicity, the threads are not shown in
The sliding elements 56, which have a keyhole contour, are inserted into openings of the first and second sleeve elements 52, 54, respectively. In the mounting condition, the free ends 14 of the hose barbs 10 are each inserted into one of the sleeve elements 52, 54 and through the larger part of the keyhole contour of the respective slide element 56, such that the sliding elements 56 are located behind the gripping edges 18. The sleeve elements 52, 54 are screwed together, pressing the free ends 14 of the hose barbs 10 against each other. In order to fully lock the hose barbs 10 into place, the sliding elements 56 are radially moved such that the rims of the smaller parts of the keyhole contours forcibly engage behind the gripping edges 18 of the hose barbs 10.
In the assembled condition shown in
Yet another embodiment of the clamping device 8 is shown in
The locking mechanism 40 comprises a sleeve 58, two snap rings 60, and two springs 62 for axially spring-loading (biasing) the snap rings 60. The snap rings 60 engage with the gripping edges 18 of the hose barbs 10 and provide an increased surface for the sleeve 58 to hold the hose barbs 10 in place. Between each snap ring 60 and a sidewall of the groove 64, the spring 62, in particular an elastomer spring or a wave spring, is located.
As an alternative to one or both springs 62, one or two O-rings 66 can be used. For illustrative purposes, an O-ring 66 is located in the left groove 64 and the spring 62 is located in the right groove 64 of the sleeve 58 in
In
Once the gripping edge 18 has been pushed through the snap ring 60 and the spring 62, they spring back into their original position and prevent the hose barb 10 from being pulled back.
While pushing the free ends 14 into the sleeve 58, the free ends 14 are also pushed between the primary and secondary sealing lips 26, 28 of the seal 20. The sleeve 58 further pushes the free ends 14 of the hose barbs 10 together and also ensures that the snap ring 60 and spring 62 engage with the gripping edges 18 of the hose barbs 10.
The locking mechanism 40 comprises a double-sided flexure bearing 68, which forms a clamp. In order to be flexible enough to widen in the mounting condition such that the free ends 14 of the hose barbs 10 can be inserted, the flexure bearing 68 comprises multiple cut-outs 70.
In
This clamping device 8 is especially suitable for the seal 20, or at least parts of the seal 20, and the locking mechanism 40 to be formed as one piece.
It is to be noted that while each of the different locking mechanisms 40 is shown with a particular seal 20, other combinations of locking mechanisms 40 and seals 20 are possible. In general, each locking mechanism 40 is only functional in combination with one of the seals 20, while each seal 20 is only functional in combination with one of the locking mechanisms 40 for the purpose of the present invention.
Number | Date | Country | Kind |
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23 170 817.3 | Apr 2023 | EP | regional |