Patent Application
20070132241
1. Field of the Invention
The present invention relates to coupling conduits.
2. Discussion of the Background Art
Couplings are used for allowing conduits adapted for conducting a medium to communicate. Known are, for example, light guides or fluid conduits for conducting light or a fluid, for example a liquid. A capillary, for example, can serve as a fluid conduit and as a light guide. Flow cells, for example, for analyzing a fluid can comprise a fluid conduit and a light guide. Flow cells can comprise different conduits communicating via one or more connections.
U.S. Pat. No. 6,526,188 B2 and the US 2001/0010747 show a modular flow cell having a high optical throughput, a long optical path length and a small cross-section. The modular flow cell configuration includes remote ports or connections for liquid and light input and liquid and light output.
U.S. Pat. No. 5,444,807 shows a flow-through cell for use in the measurement of chemical properties of small volumes of fluid containing dissolved analytes.
U.S. Pat. No. 5,608,517 discloses a coated flow cell and a method for making the coated flow cell. The flow cell comprises a flow passage, wherein light directed into the flow cell is internally reflected down the flow passage.
U.S. Pat. No. 3,236,602 discloses flow cells and holders therefore, the colorimetric examination of a liquid to determine the quantity of a substance present in the liquid.
U.S. Pat. No. 4,477,186 discloses a photometric cuvette for optical analyses of through-flowing medium, made as a thin and narrow transparent tube requiring minimum sample amounts. Light, substantially parallel to the tube length, is led obliquely into the tube through its wall, is reflected and is led obliquely out through the tube wall to a detector.
EP 008915781 discloses an optical detector cell for determining the presence of a solute in a sample fluid. The optical detector cell includes a sample tube, inlet and outlet means for the sample fluid, and a first and second optical waveguide for passing a beam of light axially through the sample tube.
GB 2193313 A discloses an apparatus and method for measuring the spectral absorbance of fluid samples. The length of the light path through the sample is adjusted to optimize the amount of light absorbed by the sample.
U.S. Pat. No. 6,281,975 B1 shows a bent capillary flow cell with protruding end bulbs coaxial with centreline of an elongated centre cylindrical section of capillary tubing. The bulbs provide a high light throughput entrance window for the cell.
It is an object of the invention to provide an improved coupling of conduits. The object is solved by the independent claims. Further embodiments are shown by the dependent claims.
According to embodiments of the present invention, a coupling comprising a first fluid conduit, a layered structure, and a first aperture is suggested. Advantageously, a fluid can be conducted through the first conduit. The first fluid conduit can comprise an end that can be coupled to another conduit. The layered structure can comprise a channel adapted for conducting a fluid. Advantageously, the channel can be coupled with the end of the first fluid conduit by the layered structure. For this purpose, the layered structure comprises a first aperture, wherein the aperture is adapted for introducing or receiving the end of the first conduit. The first conduit can be inserted into the first aperture of the layered structure for coupling the end of the first conduit with the channel of the layered structure. Besides this, the first conduit can comprise one or more ends to be coupled, wherein said layered structure is adapted for coupling said channel with one or more conduits.
Embodiments may comprise one or more of the following. The layered structure of the coupling can comprise a plurality of different layers. The different layers can comprise different functions, for example, can comprise the channel. Besides this, the layers can seal the first conduit and the channel against any leakage flow. For this purpose, the layered structure can comprise a first sealing layer. For protecting AND/OR FIXING the sealing layer, the layered structure can comprise a cover layer, for example, comprising a resistant material.
The channel leads into the aperture for coupling the channel with the end of the first conduit being inserted into the aperture. For realizing the channel, a plurality of middle layers can be combined with each other, for example, a first middle layer laminated with a second middle layer, wherein the first middle layer comprises a groove. Advantageously, a second middle layer laminated with the first middle layer and the groove of the first middle layer can confine the channel. Besides this, the channel can be realized by the first middle layer comprising a slit, wherein the first middle layer is laminated on both sides with the second middle layer and a third middle layer, wherein the slit of the first middle layer and the second and third middle layers confine the channel. Besides this, flexible layers can be combined with solid/rigid/stable parts.
In embodiments, the coupling comprises at least one middle layer comprising the channel, for example, realized as a bore and one sealing layer laminated with the first middle layer. For this purpose, the aperture can be realized as a blind hole through the sealing layer and partly through the first middle layer. For coupling the end of the conduit with the channel of the first middle layer, the channel has to end up in the aperture of the layered structure. In further embodiments, the coupling can comprise at least three layers, the first sealing layer, at least one middle layer and a second sealing layer. For this purpose, the layered structure of the coupling can comprise two apertures, wherein the second aperture is adapted for receiving a second conduit. The first sealing layer can provide a seal for the first conduit and the second sealing layer can provide a seal for the second conduit. The at least one middle layer comprises the channel adapted for conducting a fluid into at least one of the coupled conduits. For example, the channel can be adapted for channeling a fluid to an end of at least one of the conduits. The channel ends up in one of the conduits via one of the apertures.
Possibly, the coupling can be adapted for coupling a light guide and the first conduit. For this purpose, the light guide can end up in an inner tube of the first conduit, for example, in the end of the first conduit. Advantageously, the light guide can end up coaxially into the end of the first fluid conduit. Advantageously, by this, the light guide can be used for irradiating a fluid conducted within the first conduit.
For this purpose, the first and second apertures can be realized as a through hole within the layered structure adapted for introducing the ends of the first conduit and second conduit, for example, the light guide. Advantageously, by this, both conduits can be inserted into the layered structure, wherein the first conduit is inserted into the first sealing layer and the second conduit is inserted into the second sealing layer. Advantageously, the two apertures or rather the through bore of the layered structure can be realized as a stepped bore, wherein the first conduit can be inserted in the wider part of the stepped bore of the apertures. The first and second sealing layers can be laminated with the middle layers. Advantageously, any leakage flow from the first middle layer comprising the channel towards the outside of the coupling can be avoided.
Embodiments may comprise one or more of the following. The coupling can comprise a plurality of apertures, for example a plurality of pairs of apertures, wherein each pair of apertures is realized as a through hole within the layered structure of the coupling. Furthermore, at least one channel can couple at least one pair of the apertures or rather through holes. Advantageously, by this, a fluid can be channeled between at least two apertures for connecting two fluid conduits inserted into the layered structure. Additionally, each pair of apertures can receive one fluid conduit and one light guide for bringing them in communication.
Embodiments may comprise one or more of the following. Advantageously, the sealing material of the layered structure or better the sealing material of the first and second sealing layers can surround the ends of at least one conduit of said first and/or second conduits. For realizing a sealing contact between the surrounded outer surface of the conduit and the sealing material, the sealing material can be heat treated. By this, the sealing material or better the plastic material can at least BE partly plastified and/or melted. Thereafter, the plastic material can be solidified.
Advantageously, this enables a compound, for example, a chemical compound between the surface of the conduit and the plastic material. Besides this, the plastic material can shrink on the surface of the conduit by cooling it for realizing an additional bond by frictional forces. The plastic material can comprise, for example, polyetheretherketone (PEEK), one of a broad range of flouropolymeres, in particular perfluoroamines (PFA) or fluorinated ethylen-propylene copolymer (FEP), duroplastic material or compound, in particular polyimide, and/or liquid crystal polymers (LCP).
Further embodiments of the present invention relate to a fluidic system adapted for handling a fluid. The fluidic system can comprise a coupling. Advantageously, the coupling can be adapted for connecting, sealing, fixing, adjusting, aligning, receiving, protecting, and positioning a first conduit. Besides this, the fluidic system can comprise a flow cell for housing a fluid sample and for exposing the fluid sample to radiation for analyzis. Advantageously, the flow cell can comprise at least one of the couplings.
Finally, embodiments of the invention relate to a method of coupling the first conduit with the channel by the coupling. The ends of the first conduit can be inserted partly into the first aperture. The sealing material of the layered structure of the coupling can be heated at least partly. Advantageously, by this, the sealing material can be plastified and/or melted at least partly.
Other objects and many of the attendant advantages of embodiments of the present invention will be readily appreciated and become better understood by reference to the following more detailed description of embodiments in connection with the accompanied drawings. Features that are substantially or functionally equal or similar will be referred to by the same reference signs.
The layered structure 3 of the coupling 1 comprises a plurality of layers laminated to each other. More precisely, the layered structure 3 comprises a first cover layer 11 and a second cover layer 13. The first and second cover layers 11 and 13 are adapted for protecting a first sealing layer 15 and a second sealing layer 17 of the coupling 1. The first and second sealing layers 15 and 17 each are laminated to one of the first and second cover layers 11 and 13. The first and second sealing layers 15 and 17 each comprise a sealing material comprising a plastic material 19. The plastic material 19 can be adapted for being at least partly plastified and/or melted and for surrounding an outer surface 21 of the first fluid conduit 5 and an outer surface 23 of the second conduit 7 or rather the light guide 9 in a sealing contact. The plastic material 19 of the second sealing layer 17 surrounds the outer surface 23 of the light guide 9 and the first sealing layer 15 surrounds the outer surface 21 of the first conduit 5 for sealing a fluid path 25 of the coupling 1 against any leakage flow.
The fluid path 25 of the coupling 1 comprises a channel 27 provided by a first middle layer 29 and a second middle layer 31. The first middle layer 29 and the second middle layer 31 are laminated to each other, wherein the first middle layer 29 comprises a groove 33. The groove 33 of the first middle layer 29 is covered by the second middle layer 31. By this, the channel 27 of the fluid path 25 of the coupling 1 can be provided and confined.
Furthermore, the fluid path 25 comprises a circular gap 35. The circular gap 35 is realized by a first aperture 37 within the layered structure 3 of the coupling 1. The channel 27 of the fluid path 25 ends up in the first aperture 37 of the coupling 1. The first aperture 37 can be realized as a bore through the first cover layer 11, the first sealing layer 15, and the second middle layer 31. The diameter of the bores of the first cover layer 11 and the second middle layer 31 are adapted to the outer diameter of the outer surface 21 of the first fluid conduit 5.
Advantageously, by this, the first fluid conduit 5 can be inserted into the bores of the first aperture 37 of the layered structure 3, for example, in a loose fit or in a press fit. An end 39 of the first fluid conduit 5 is inserted into the first aperture 37. As shown in the
The light guide 9 comprises an optical outlet 45 inserted through the second aperture 43 partly into the inner tube 41 of the first fluid conduit 5. By this, a fluid conducted within the inner tube 41 of the first fluid conduit can be irradiated by the light guide 9. The outer diameter of the light guide 9 is smaller than the inner diameter of the inner tube 41 of the first fluid conduit 5. By this, a circular gap 47 remains. The circular gap is adapted for conducting a fluid and is part of the fluid path 25. Advantageously, such a coupling can be used for providing a flow cell.
As can be seen in
For sealing the fluid path 25 of the coupling 1, the coupling 1 can be heat treated. Firstly, the first fluid conduit 5 and the second conduit 7 or rather the light guide 9 can be inserted in the according apertures 37 and 43. For example, firstly, the first fluid conduit 5 can be inserted into the first aperture 37, and thereafter the second conduit 7 can be inserted into the second aperture 43 and additional into the inner tube 25 of the first conduit 5. Thereafter, the fluid path 25 of the coupling 1 can be sealed by the first and second sealing layers 15 and 17. For this purpose, the plastic material 19 of the first and second sealing layers 15 and 17 can be heated, for example, at least partly nearby the outer surfaces 21 and 23 of the first and second conduits 5 and 7. This can be realized, for example, by inducing a current, and/or by leading a hot fluid through the flow path 25 or alike. In other embodiments, the complete coupling 1 can be heated for plastifying and/or melting the plastic material 19 of the first and second sealing layer 15 and 17. Possibly, the sealing contact of the plastic material 19 of the first and second sealing layers 15 and 17 with the outer surfaces 21 and 23 of the first and second fluid conduits 5 and 7 can be realized by exerting pressure to the layered structure 3 of the coupling 1. The layered structure 3 can be pressed, for example, by a not shown tool in direction of two arrows 53. By pressing and/or heating the plastic material 19, the circular gaps 47—as shown in
The inner bore 49 comprises an inner surface 47 confining the circular gap 51—before heating,
After heating the sealing material or better the plastic material 19 for plastifying and/or melting, the plastic material can be solidified. By this, the first and second conduits 5 and 7 can be sealed and fixed within the first and second apertures 37 and 43. Possibly, the plastic material 19 can be heated and solidified within a tool. For this purpose, possibly, the first and second cover layers 11 and 13 are not necessary. Consequently, the coupling 1 can be provided without the first and second cover layers 11 and 13. In other embodiments, the coupling 1 can comprise an additional not shown housing, for example, instead of the first and second cover layers 11 and 13 and for confining the plastic material 19 within the housing.
Between the fluid source 203 and the fluid sink 205, the fluidic system 201 comprises a fluid path 207. The fluid path 207 is coupled with at least one light path 209. Possibly, the fluid path 207 of the fluidic system 201 can be coupled with a second light path 211. The fluid path 207 and the first and second light paths 209 and 211 belong to a first and a second flow cell 213 and 215.
For coupling the fluid path 207 and the first and second light paths 209 and 211, the fluidic system 201 comprises at least one coupling 217. The coupling 217 can be realized according to one of the couplings according to the Figures above.
Each of the flow cells 213 and 215 comprises a capillary 219 and comprises a wave guide 221. The capillaries 219 of the first and second flow cells 213 and 215 are adapted for conducting a fluid, for example, a fluid comprising a sample, for example, a sample dissolved in a liquid. For analyzing the sample of the fluid, the fluid can be irradiated by the wave guides 221 of the light paths 209 of the first and second flow cells 213 and 215. For measuring the amount of light guided through the fluid sample, the light paths 209 can be connected to not shown light detectors. The wave guide 221 can also be an optical element like a window, glass rod, and/or alike.
Furthermore, the coupling/s 217 can comprise a plurality of communicating branches, for example, for coupling the capillaries 219, the wave guides 213, and/or according supplying or rather draining conduits to each other.
The direction of the light guided though the light paths 209 of the first and second flow cells 213 and 215 is indicated by arrows 223. The direction of the fluid guided though the fluid paths 207 of the first and second flow cells 213 and 215 is indicated by arrows 225. Besides this, different beams of the light paths 209 are indicated by lines 231.
The capillaries 219 of the first and second flow cells 213 and 215 can comprise a transparent material, for example glass, quartz glass, and/or alike, wherein within the walls of the capillaries total reflection can occur as shown by the beams as indicated by the lines 231 of
The fluid source 203 can comprise a separating device 227 and/or can be coupled with such a device. Besides this, the fluid sink 205 can comprise an analyzing device 229, for example, a mass spectrograph. The fluidic system 201 can be realized as an integrated system for analysis purposes, for example as a integrated system commercially available, for example, a chromatographic system (LC), a high performance liquid chromatographic (HPLC) system, an HPLC arrangement comprising a chip and an mass spectrograph (MS), a high throughput LC/MS system, a purification system, a micro fraction collection/spotting system, a system adapted for identifying proteins, a system comprising a GPC/SEC column, a nanoflow LC system, and/or a multidimensional LC system adapted for separation of protein digests.
The fluidic system 201 can be adapted for analyzing liquid. More specifically, the fluidic system 201 can be adapted for executing at least one microfluidic process, for example an electrophoresis and/or a liquid chromatographic process, for example a high performance liquid chromatographic process (HPLC). Therefore, the fluidic system 201 can be coupled to a liquid delivery system, in particular to a pump, and/or to a power source. For analyzing liquid or rather one or more components within the liquid, the fluidic system 201 can comprise a detection area, such as an optical detection area and/or an electrical detection area being arranged close to a flow path within the fluidic system 201. Otherwise, the fluidic system 201 can be coupled to a laboratory apparatus, for example to a mass spectrometer, for analyzing the liquid. For executing an electrophoresis, the flow path can comprise a gel. Besides this, the fluidic system can be a component part of a laboratory arrangement.
It is to be understood, that this invention is not limited to the particular component parts of the devices described or to process steps of the methods described as such devices and methods may vary. It is also to be understood, that different features as described in different embodiments, for example illustrated with different Fig., may be combined to new embodiments. It is finally to be understood, that the terminology used herein is for the purposes of describing particular embodiments only and it is not intended to be limiting. It must be noted, that as used in the specification and the appended claims, the singular forms of “a”, “an”, and “the” include plural referents until the context clearly dictates otherwise. Thus, for example, the reference to “a coupling” or “a fluid path” may include two or more such functional elements.
