COUPLING DEVICE FOR FLUID LINES

Description

[0001] The present invention relates to a coupling device for fluid lines, which comprises a receiving unit and a plug-in unit.

[0002] Coupling devices designed to connect two fluid lines are known from the prior art. However, this usually results in the problem that fluid dynamics at the coupling point are significantly worse than those in the rest of the fluid line, as the components of the coupling device can cause turbulence and dead zones in the fluid being conveyed. Particularly when using elements that are preloaded into a specific position by spring elements, a spring element can cause severe disruption of the fluid flow in the area of ​​the coupling device.

[0003] Furthermore, the presence of dead zones can lead to an accumulation of fluid within the coupling device, which can then escape uncontrollably when the coupling device is disconnected. This can lead to environmental contamination or, for example, in the case of hazardous substances transported within the fluid line, to harm the environment and / or the operator of the coupling device.

[0004] Document DE 100 13 488 A1, which is considered the closest prior art, discloses a coupling device for fluid lines whose receiving unit is configured so that its fluid flow channel can be fluidically sealed or opened by means of a closure element. Further reference is made to documents US 5 540 250 A, US 2014 / 083542 A1, US 2017 / 307123 A1, FR 2 166 770 A5, US 2 322 877 A, WO 2019 / 190658 A1, and US 4 700 743 A.

[0005] It is therefore the object of the present invention to provide a coupling device for fluid lines whose flow properties are improved and at the same time corresponding dead zones are reduced.

[0006] This object is achieved according to the invention by a coupling device for fluid lines according to claim 1.

[0007] The inventive arrangement of the coupling device or the receiving unit enables the spring element to be arranged separately from the fluid flowing through the receiving unit, at least in the release position of the associated closure element, in which passage of fluid through the receiving unit is possible, thereby achieving improved fluid flow through the receiving unit. Furthermore, this prevents fluid from accumulating in the region in which the spring is arranged and escaping from the receiving unit in an uncontrolled manner upon release of the coupling device, i.e., the receiving unit from a complementary plug-in unit.The closure element can be constructed in several parts, in particular in two parts, whereby the individual components of the closure element can be connected to one another, for example via matching internal and external threads, in order to simplify the assembly of the closure element.

[0008] The receiving unit can in particular be designed to be connectable to a, in particular standardized, standard plug-in unit.

[0009] It should be mentioned at this point that the receiving unit or the entire higher-level coupling device can, of course, be configured to connect both smooth pipes and corrugated pipes. It is advisable for connecting sections of the coupling device, at which the coupling device is to be connected to corresponding fluid lines, to have a connecting piece with a sawtooth profile. In addition, such a connecting piece can be provided with at least one groove in which a sealing element, such as an O-ring, can be received to seal against the fluid line.

[0010] For better guidance in the receiving unit, the closure element can have a plurality of ribs, in particular at least three ribs, on its outer circumference, which protrude radially outwards from the closure element and can come into contact with a respective section of the surrounding receiving unit at their radially outer end.

[0011] In particular, the spring element can be a wave spring. Compared to a coil spring, a wave spring requires less space while providing the same spring force.

[0012] Advantageously, the spring element can be arranged radially outside the cylindrical portion. Thus, the cylindrical portion can shield the spring element from the radially inner flow channel on the inner circumference of the spring element.

[0013] In a further development of the present invention, the perforations of the partial section can be designed as four window-like openings. In particular, the perforations are arranged such that, when the closure element has left its closed position, fluid flows through the perforations from radially outside the closure element to radially inside, or vice versa in the case of an opposite flow direction. Thus, the cylindrical, perforation-free section of the closure element can also interact with the receiving unit, for example, a projection of the receiving unit, such that essentially all fluid reaching the area of ​​the perforations in the closure element is guided through the perforations into the interior of the closure element, instead of flowing radially outside of them.

[0014] The receiving unit can have a housing in which the closure element is received, wherein the housing can have a radially inwardly extending projection which is designed to come into contact with the closure element, in particular a sealing element arranged on the closure element, in the closed position of the closure element. The sealing element can be formed separately from the closure element, for example as an O-ring. As already described above, this projection can be designed to come into contact both with the sealing element in the closed position of the closure element and with the cylindrical section of the closure element, in particular in the release position of the closure element. The projection can in particular be formed integrally with the housing of the receiving unit.

[0015] For this purpose, the projection can be provided with an inclined flank, so that the projection results in a gradually decreasing cross-section of the interior of the housing in a direction from the release position to the closed position of the closure element. Such a projection can be used to guide and center the closure element, for example, when moving into the closed position. The inclined flanks can provide the sealing element with a defined sealing surface to engage, so that sealing by the sealing element can be ensured. Furthermore, the inclined flanks can guide the fluid flow from radially outward through the openings in the closure element to radially inward, thus improving it.

[0016] The housing of the receiving unit can be designed in multiple parts, in particular in two parts. In particular, the housing of the receiving unit can be designed in multiple parts, viewed in an axial direction of the movement axis of the closure element between the closed position and the release position. This means that the housing of the receiving unit can, for example, comprise a substantially tubular section which has the radially inwardly projecting projection, and further comprise a closing element on which a connecting section, in particular a nozzle element, is formed with the first end of the receiving unit for connection to a fluid line. The division of the housing into a tubular section and a closing element can enable the closure element to be inserted partially from one side of the receiving unit and partially from the other side of the receiving unit and to be mounted within the receiving unit.

[0017] A first housing part, which comprises the first end, can be connected in a fluid-tight manner to a second housing part, which comprises the second end, in particular using a spin welding process or a laser welding process. For example, the above-described closure element can be connected in a fluid-tight manner to the tubular portion at one end face thereof.

[0018] Advantageously, at least one protruding web can be arranged on the housing, which is configured to define the release position of the closure element when it rests against the closure element. The release position of the closure element can be defined, in particular, by the closure element resting against the free end of the at least one web. The webs can, for example, be arranged circumferentially around an opening of a fluid flow channel formed radially within the nozzle element and extend from there toward the tubular portion of the housing of the receiving unit.This means that in the release position of the closure element, fluid which emerges from the fluid flow channel within the nozzle element flows radially outwards between the webs, flows around the section of the closure element on which the sealing element is arranged, and flows from there radially inwards through the through-openings of the closure element and through the closure element out of the receiving unit.

[0019] As already indicated above, for the sake of simplicity, this description will primarily focus on the flow direction from the receiving unit to the plug-in unit. However, the receiving unit according to the invention and the coupling device according to the invention are, of course, equally suitable for an opposite flow direction. The coupling device can, in particular, be designed for pressures of a fluid flowing therein of 2 bar to 5 bar.

[0020] According to the invention, the counter-contact surface of the closure element of the receiving unit is designed as a collar projecting radially from the closure element of the receiving unit. The radially projecting collar, which is formed in particular on an end face of the cylindrical portion of the closure element facing the plug-in unit, allows the surface area of ​​the counter-contact surface to be enlarged, thus preventing, for example, the contact surface of the plug-in unit from sliding off the counter-contact surface. The spring element, which preloads the closure element of the receiving unit into the closed position, can be supported on the side of the collar opposite the counter-contact surface for contacting the plug-in unit.The other end of the spring element of the receiving unit can, for example, be supported on the projection of the housing of the receiving unit, in particular a flank of the projection extending in the radial direction to the housing of the receiving unit.

[0021] In a further development of the present invention, the plug-in unit can also comprise a closure element which, in a closed position, is configured to fluidically seal the fluid flow channel of the plug-in unit between a second end opposite the first end with respect to a main flow direction along the fluid flow channel and the first end of the plug-in unit, wherein the closure element of the plug-in unit is displaceable between the closed position and a release position, wherein the closure element of the plug-in unit is preloaded into the closed position using a spring element. The spring element can be arranged on the side of the closure element of the plug-in unit facing the first end. The spring element of the plug-in unit can also be a wave spring.

[0022] Analogous to the multi-part construction of the housing of the receiving unit described above, a housing of the plug-in unit can also be constructed in several parts, in particular in two parts. Here, too, a substantially tubular section can be fluid-tightly connected at one end face to a closure element, on which a connecting piece for connection to a fluid line is arranged.

[0023] The plug-in unit can have, in particular on the end face of the tubular section of the housing of the plug-in unit opposite the closure element, a projection projecting radially inwardly, which, as described above with respect to the receiving unit, can have an oblique flank, via which the closure element of the plug-in unit can be centered and which offers a corresponding contact surface to a sealing element arranged on the closure element of the plug-in unit.

[0024] The closure element of the plug-in unit can have an increasing diameter in a direction from the second end of the plug-in unit to the first end of the plug-in unit. For example, the closure element of the plug-in unit can comprise a first substantially cylindrical section, on the outer circumference of which the sealing element is arranged for sealing against the housing of the plug-in unit. Viewed in the flow direction of the fluid from the receiving unit to the plug-in unit, the first cylindrical section can be followed by a conical section, over which an outer diameter of the closure element of the plug-in unit increases. This can be followed by a second substantially cylindrical section whose outer diameter is larger than that of the first cylindrical section.Sector-like openings can be provided in the area of ​​the conical section, so that the second cylindrical section, which is designed as a ring, can be connected to the first cylindrical section only via remaining webs. This means that, in the release position of the closure element of the plug-in unit, fluid can flow past the outer circumference of the first cylindrical section of the closure element of the plug-in unit and then flow radially inward through the second cylindrical section via the openings in the conical section.

[0025] This nozzle-like shape of the closure element of the plug-in unit can largely reduce turbulence in the fluid flow in the area of ​​the plug-in element, so that a high flow velocity through the plug-in element can be achieved.

[0026] When the spring element rests against the free end face of the second cylindrical section, the fluid also flows radially inward through the spring element.

[0027] According to the invention, the closure element of the receiving unit has a central bolt which has a free end extending in the direction of the second end of the receiving unit and which is designed, upon insertion of the plug-in unit into the receiving unit, in particular with its free end, to bear against a bolt-receiving surface formed on the closure element of the plug-in unit, so that, upon continued insertion of the plug-in unit into the receiving unit, the closure element of the plug-in unit or the closure element of the receiving unit is displaced from its closed position towards the release position. The bolt-receiving surface can be formed, in particular, on a free end face of the first cylindrical section of the closure element of the plug-in unit.

[0028] In this case, the bolt of the closure element of the receiving unit and / or the bolt receiving surface of the closure element of the plug-in unit can be dimensioned such that the bolt only comes into contact with the bolt receiving surface when the housing of the plug-in unit has come into contact with a sealing device which is arranged on the receiving unit and which is configured to seal between the receiving unit and the plug-in unit, so that fluid can be prevented from escaping from the coupling device to an outside.

[0029] A spring force of the spring element acting on the closure element of the plug-in unit can be lower, in particular significantly lower, than a spring force of the spring element acting on the closure element of the receiving unit, so that, upon insertion of the plug-in unit into the receiving unit, first the closure element of the plug-in unit is displaced from its closed position into its release position and then, upon continuation of the insertion of the plug-in unit into the receiving unit, the closure element of the receiving unit is displaced from its closed position into its release position.In this way, assuming that the fluid flow direction through the coupling device runs from the receiving unit to the plug-in unit, it can be ensured that a fluid flow through the receiving unit and thus through the coupling device is only permitted when the plug-in unit is already completely opened, i.e. the closure element of the plug-in unit is in the release position.

[0030] For example, the coupling device can be secured in its coupled state between the receiving unit and the plug-in unit by means of a securing element to prevent the plug-in unit from becoming detached from the receiving unit.

[0031] The receiving unit and / or the plug-in unit and / or the respective closure element can be made of plastic, in particular of polyamide, advantageously of PA6 GF30.

[0032] In the following, the present invention will be described in more detail using preferred embodiments with reference to the accompanying drawings. It shows: Figure 1 shows a perspective exploded view of a coupling device according to the invention in accordance with a first exemplary embodiment; Figure 2 shows a side cross-sectional view of a receiving unit according to the first exemplary embodiment; Figure 3 shows a side cross-sectional view of a plug-in unit; Figure 4 shows a side cross-sectional view of a coupling device according to the invention in accordance with the first exemplary embodiment, wherein a flow of fluid is blocked; Figure 5 shows a side cross-sectional view of the coupling device according to the invention from Figure 4, wherein a flow of fluid is permitted; Figure 6 is a side cross-sectional view of a receiving unit according to a second embodiment, wherein a flow of fluid is blocked; Figure 7 is a side cross-sectional view of the receiving unit from Figure 6 , wherein a flow of fluid is permitted; Figure 8 a perspective view of a closure element of the embodiment of Figure 6 and 7 and Figure 9 shows a side cross-sectional view of a coupling device according to the invention, based on the receiving unit of the second embodiment and a plug-in unit matching the receiving unit.

[0033] In Figure 1a coupling device according to the invention according to a first embodiment is generally designated by the reference numeral 10. The coupling device 10 comprises a receiving unit 12 and a plug-in unit 14. The receiving unit 12 comprises a housing 16, which in turn comprises a substantially tubular section 18 and a closure element 20, wherein the closure element 20 is provided with a (in Figure 1 (shown on the left) end face of the tubular section 18. In the first embodiment, a nozzle element 22 is formed on the end element 20, to which a fluid line, such as a smooth tube, can be coupled. A groove 24 is provided on the nozzle element 22 to accommodate a sealing element 26, here an O-ring.

[0034] Within the housing 16 of the receiving unit 12, a wave spring 28 is arranged, which at one end bears against a projection 30 (see Figure 2) of the tubular portion 18 of the housing 16 of the receiving unit, which projects radially inward and is supported at its other end against a collar 32 of a closure element 34.

[0035] The closure element 34 comprises a cylindrical section 36 adjoining the collar 32, which is designed without any openings, to which in turn (in Figure 1 left) is adjoined by a section 40 provided with perforations 38. On that side of the perforated section 40 of the closure element 34 which is opposite the cylindrical section 36, a sealing element receiving section 42 is provided, which is designed to receive a sealing element 44. The sealing element 44 is designed to seal the closure element 34 against an inner wall, in particular the projection 30, of the housing 16 of the receiving unit 12.

[0036] In Figure 1To the right of the closure element 34 of the receiving unit 12, a sealing device 46 is shown, which is arranged on an inner side of the housing 16 or the tubular section 18 of the housing 16 of the receiving unit 12 in order to seal the receiving unit 12 with respect to the plug-in unit 14, so that fluid can be prevented from escaping to the outside between the receiving unit 12 and the plug-in unit 14.

[0037] The plug-in unit 14 comprises a housing 48, which comprises a substantially tubular portion 50 and a further closure element 52, wherein the further closure element 52 is generally designed analogously to the closure element 20 of the receiving unit 12. Within the housing 48 of the plug-in unit 14, a closure element 54 of the plug-in unit 14 is arranged (see also Figure 3), which comprises a first cylindrical portion 56, on which a sealing element 58 is received, a conical portion 60, along which the outer diameter of the closure element 54 of the plug-in unit 14 increases, and a second cylindrical portion 62. The free end (which in Figure 1 end shown on the right) of the second cylindrical section 62 of the closure element 54 of the plug-in unit 14 is in contact with a wave spring 64 of the plug-in unit 14, which, under support against the further end element 52 of the plug-in unit 14, the closure element 54 (in Figure 1 to the left).

[0038] In Figure 1Furthermore, a securing element 66 can be seen which, in a fully connected state of the receiving unit 12 and the plug-in unit 14, can be releasably inserted in a radial direction to the coupling device 10 through a receiving space 68 of the receiving unit 12 and into a receiving groove 70 of the plug-in unit 14 in order to prevent an axial displacement of the plug-in unit 14 relative to the receiving unit 12 and thus a release of the coupling device 10.

[0039] In Figure 2 An enlarged side cross-sectional view of the receiving unit 12 in its assembled state is shown. It can be seen that the wave spring 28 presses the closure element 34 of the receiving unit 12 into the Figure 2shown closed position. In this closed position of the closure element 34 of the receiving unit 12, the sealing element 44 effects a fluidic seal between the closure element 34 and the projection 30 of the housing 16 of the receiving unit 12. Thus, fluid, which is assumed here to flow in the flow direction indicated by arrow A, is prevented from flowing past the sealing element 44.

[0040] Furthermore, in the side cross-sectional view of Figure 2 It can be seen that the closure element 34 has a central bolt 72 which projects in the direction of that side of the receiving unit 16 via which the plug-in unit 14 can be inserted into the receiving unit 12.

[0041] In Figure 3a side cross-sectional view of the plug-in unit 14 is shown. Here, too, the spring 64 biases the closure element 54 of the plug-in unit 14 towards its closed position, i.e., into a position in which the sealing element 58 is in contact with the tubular portion 50 of the housing 48 of the plug-in unit 14 in such a way that a passage of fluid can be prevented. A bolt receiving surface 74 is formed on a free end face of the first cylindrical portion 56 of the closure element 54 of the plug-in unit 14 (see the following detailed description in relation to Figure 4 and 5 ).

[0042] Figure 4shows the coupling device 10 according to the invention in a partially connected state, namely a state in which the plug-in unit 14 has already been partially inserted into the receiving unit 12 and an outer circumference of the tubular section 50 of the housing 48 of the plug-in unit 14 has at least partially come into sealing contact with the sealing device 46 of the receiving unit 12. However, in the partially connected state of Figure 4 both the closure element 34 of the receiving unit 12 and the closure element 54 of the plug-in unit 14 are still in their respective closed position, so that the passage of fluid through the coupling device 10 is prevented. The central bolt 72 is in Figure 4 has already come into contact with the bolt receiving surface 74 of the plug-in unit 14.

[0043] If the plug-in unit 14 is now moved further into the receiving unit 12, the fully connected state is achieved at the end of this insertion according to Figure 5 reached. In Figure 5 both the closure element 34 of the receiving unit 12 and the closure element 54 of the plug-in unit 14 are arranged in their release position so that fluid can flow through the coupling device 10 in the fluid flow direction indicated by the arrow A.

[0044] Although not shown, it should be assumed for the embodiment of the coupling device 10 according to the invention shown in the figures that a spring rate of the wave spring 64 of the plug-in unit 14 is lower than a spring rate of the wave spring 28 of the receiving unit 12, so that upon further insertion of the plug-in unit 14 into the receiving unit 12, after the Figure 4shown position, first the wave spring 64 is compressed and thus the closure element 54 of the plug-in unit 14 is moved from its closed position into the release position according to Figure 5 is displaced by the action of the bolt 72. Once the wave spring 64 has reached its maximum compression or the closure element 54 of the plug-in unit 14 rests against a corresponding stop, further insertion of the plug-in unit 14 into the receiving unit 12 displaces the closure element 34 of the receiving unit 12 from its closed position into the release position. Only at this point is the fluid permitted to flow past the sealing element 44, which is arranged on the closure element 34 of the receiving unit 12, and into the plug-in unit 14.

[0045] In its release position, the closure element 34 of the receiving unit 12 according to the first embodiment rests against webs 76, which protrude from the end element 20 of the housing 16 of the receiving unit 12. The release position is defined by the contact between the closure element 34 of the receiving unit 12 and the webs 76.

[0046] With reference to the Figure 5 In the position of the coupling device 10 shown, the fluid flows through a fluid line (not shown) into the receiving unit 12, that is to say the fluid flow channel formed within the closure element 20 of the housing 16 of the receiving unit 12, from there between the webs 76 radially outwards and radially outwards around the sealing element 44 and the corresponding section of the closure element 34 of the receiving unit 12 (see the curved arrow A in Figure 5), then the fluid flows radially inward via the openings 38 of the closure element 34 of the receiving unit 12 and along the central bolt 72 from the receiving unit 12 into the plug-in unit 14. In the plug-in unit 14, the fluid flows radially outward around the first cylindrical section 56 and the sealing element 58 of the closure element 54 of the plug-in unit 14, then through sector-like openings 78 (see Figure 1 ) through the interior of the wave spring 64 and via a fluid flow channel formed within the end element 52 of the housing 48 of the plug-in unit 14 from the coupling device 10 into a fluid line (again not shown).

[0047] As in particular the Figure 5 can be seen, the spring 28, in which in Figure 5illustrated fully connected state of the coupling device 10, is arranged within a receiving space 80 which is delimited radially inwardly by the cylindrical, perforation-free section 36 of the closure element 34 of the receiving unit 12, radially outwardly by the tubular section 18 of the housing 16 of the receiving unit 12, and in the axial direction at the front and rear by the collar 32 of the closure element 34 of the receiving unit 12 and by the projection 30 of the housing 16 of the receiving unit 12. The wave spring 28 can thus be separated from the fluid flow path in the release position of the closure element 34 of the receiving unit 12, so that the discontinuous structure of the wave spring 28 cannot cause any turbulence in the fluid flow which occurs within the receiving unit 12.

[0048] It should also be added that, alternatively or in addition to the contact of the bolt 72 and the bolt receiving surface 74, a contact surface 82 (see Figure 3 and 5 ) of the plug-in unit 14, which in the figures is formed by way of example on the housing 48 of the plug-in unit 14, can come into contact with a counter-contact surface on the closure element 34 of the receiving unit 12, which in the figures is formed on the side of the collar 32 of the closure element 34 opposite the spring 28, in order to bring about a displacement of the closure elements 34 and 54 upon insertion of the plug-in unit 14 into the receiving unit 12.

[0049] In the following, with reference to Figure 6A second embodiment of a receiving unit 112 according to the invention is described, which is a modification of the previously described receiving unit 12. Therefore, only the differences from the first embodiment will be discussed in more detail below, and reference is made to the first embodiment with regard to all other features and functions. Accordingly, all features, effects, and advantages disclosed with respect to the first embodiment of the receiving unit 12 (or the associated coupling device 10) can be equally applicable to the second embodiment of the receiving unit 112 (or the associated coupling device 110), and vice versa.

[0050] In Figure 6A side cross-sectional view of the receiving unit 112 of the second embodiment is shown in an assembled state, wherein a flow of fluid is blocked in the given illustration. In comparison to the receiving unit 12 of the first embodiment, the closing element 120 of the receiving unit 112 here has no groove or sealing element at its first end, although these can be provided optionally. Analogous to the sealing device 46 of the first embodiment, a sealing device 146 is also provided in the receiving unit 112 (O-rings and spacers not shown here), which seals the receiving unit 112 from the outside relative to the plug-in unit 114.

[0051] The closure element 134 of the receiving unit 112 differs from the closure element 34 of the first exemplary embodiment in particular due to its multi-part construction. Here, the closure element 134 comprises internal and external threads arranged parallel to the flow direction A, which are designated together with the reference numeral 135, via which an end section 190 of the closure element 134 and a lower element 133 of the closure element 134 are attached to one another. During the assembly of the closure element 134, the end section 190 and the lower element 133 can alternatively or additionally be connected to one another, for example by welding, riveting, or caulking, in order to ensure a completely sealed connection between the end section 190 and the lower element 133. The end section 190 has webs 194 extending radially outward (see Figure 8), the free ends of which are arranged close to or in contact with an inner surface of the housing 116. The end section 190 preferably has at least three webs 194, according to the second embodiment shown here, four webs 194. Conical surfaces are arranged at the free ends of the webs 194, which bear against the housing 116 when the closure element 134 is in the closed position. This can prevent the closure element 134 from being displaced beyond the closed position or a sealing element 144 from being damaged or displaced from its receptacle.

[0052] In the Figure 6In the closed position of the closure element 134 shown, the sealing element 144, which is received between the end section 190 and the lower element 133, effects a fluidic seal between a flow space upstream of the closure element 134 and a flow space downstream of the closure element 134. The use of the end section 190 has the further advantage that the webs 194 of the end section 190 secure the O-ring 144 against displacement from its receptacle.

[0053] Analogous to the Figure 5 described release position of the receiving unit 12 is in Figure 7the closure element 134 of the receiving unit 112 is shown in the release position, whereby a fluid flow along the flow direction A over the entire length of the receiving unit 112 is enabled. In contrast to the first embodiment, no webs 76 are provided in the closing element 120 of the housing 116, since the fluid flows through openings 196 (see Fig. 8 ; in Figure 7(not shown) of the end section 190. The fluid then flows radially outwardly around the sealing element 144 and around an immediately adjacent part of the lower element 133 according to the further course of a tubular section 118 of the receiving unit 112. The fluid passes radially inward via openings 138 and then flows past a central bolt 172 within a cylindrical section 136 of the closure element 134. Due to the axial arrangement of the bolt 172, the previously radial flow is converted into an axial flow in such a way that undesired turbulence or stagnation effects are reduced or even avoided. The fluid then flows further within a plug-in unit 114 (not shown here but described further below).

[0054] Figure 8shows a perspective view of the closure element 134, comprising the end section 190 and the lower element 133, as already mentioned above. It can be seen that the end section 190 comprises a plate-shaped base section 192 and several, here four, webs 194 projecting radially from the base section 192. Between the individual projecting webs 194, the openings 196 are provided, through which fluid can pass in the release position of the closure element 134. Furthermore, Figure 8 the arrangement of the window-like openings 138 of the lower element 133, which are designed to establish a fluidic connection between an exterior and an interior of the closure element 134.

[0055] A second embodiment of a coupling device 110 according to the invention is shown in Figure 9shown in a side cross-sectional view. In contrast to the coupling device 10 of the first embodiment, the coupling device 110 has the previously described receiving unit 112 and a plug-in unit 114, in which a closure element 154 is received analogously to the plug-in unit 14. The housing 148 of the plug-in unit 114 is here formed in two parts, comprising a tubular section 150 and a further closing element 152, which, analogously to the further closing element 52, can be connected to a fluid line (not shown) and can optionally have sealing elements for this purpose, wherein a fluid outlet (or fluid inlet in the case of the reverse flow direction) of the closing element 152 is arranged at an angle, here at right angles, to the longitudinal extension of the coupling device 110. For the sake of completeness, it should be mentioned that, although the plug-in unit 114 in Figure 9Although it is shown angled, this does not necessarily have to be the case. The tubular section 150 and the further end element 152 are connected to one another in a fluid-tight manner.

[0056] A wave spring 164 is accommodated within the plug-in unit 114, which preloads the closure element 154 of the plug-in unit 114 into its closed position. The wave spring 164 is held in a spring receptacle 163, which is formed integrally with the further closure element 152 and protrudes annularly into its interior. When the closure element 154 is displaced from its release position to its closed position, a sealing element 158, which is received radially outward on the closure element 154 of the plug-in unit 114, initially comes into contact with a tapered contact surface 165, whereby the sealing element 158 ​​is compressed radially inward. Due to the action of the wave spring 164, the closure element 154 is displaced further until a stop surface 167 of the closure element 154 strikes against a counter-stop surface 169, which is formed on the housing 148 of the plug-in unit 114.The contact between the stop surface 167 and the counter-stop surface 169 thus defines the closed position of the closure element 154. In this closed position, the sealing element 158 ​​bears against a cylindrical sealing surface 171, whereby the elastic restoring force of the sealing element 158, which acts essentially orthogonally to the sealing surface 171, supports the sealing effect. Such a cylindrical sealing surface can of course be provided analogously on the receiving unit, which interacts with the sealing element 144.

[0057] The connection process of the coupling device 110 will now be described in more detail below. When the plug-in unit 114 is inserted into the receiving unit 112, a contact surface 151 of the closure element 134 of the receiving unit 112 first contacts a counter-contact surface 153 of the closure element 154 of the plug-in unit 114. Upon further insertion of the plug-in unit 114 into the receiving unit 112, depending on the design of the spring forces of the wave end springs 28, 164, at least one of the two closure elements 134, 154 is displaced from its closed position towards its release position. In the Figure 9In the example shown, the spring force of the wave spring 164 is less than the spring force of the wave spring 28, so that the closure element 154 of the plug-in unit 114 is first displaced from its closed position into its release position. Subsequently, a contact surface 132 of the closure element 134 of the receiving unit 112 contacts a counter-contact surface 182 of the housing 148 of the plug-in unit 114, whereby the closure element 134 is also displaced from its closed position toward its release position.

[0058] Now a fluid flows from the Figure 9If the fluid flows along the receiving unit 112 shown on the left into the plug-in unit 114, the fluid is deflected radially outwards by a wedge-shaped base 159 and then passes through openings 161 into the end element 152 of the plug-in unit 114. In the release position of the closure element 154, an annular spring receiving section 173 of the closure element 154, in which the free end of the wave spring 164 is received which is not received in the spring receptacle 163, contacts the spring receptacle 163 or is at least arranged adjacent to it, whereby the release position of the closure element 154 is defined. By the contact orthe proximity of the two annular parts, namely spring receptacle 163 and spring receptacle section 173, the wave spring 164 is taken out of contact with the fluid flowing past, so that because the fluid does not come into contact with the wave spring 164, turbulence in this area of ​​the plug-in unit 114 is minimized and no fluid deposits can occur on the wave spring 164.

[0059] The closure element 154 is at its in Figure 9 The free end shown on the left is guided over a radial thickening within the tubular section 150 of the housing 148.

[0060] A locking device 175 is formed radially outside on the closure element 154 of the plug-in unit 114, which is designed to lock onto the receiving unit 112 in order to prevent undesired decoupling between the receiving unit 112 and the plug-in unit 114.

Claims

1. Coupling device (10, 110) for fluid lines, comprising a receiving unit (12, 112) and a plug-in unit (14, 114), wherein the receiving unit (12, 112) is designed to be connected at a first end (22) to a fluid line not belonging to the receiving unit (12, 112), and which defines a fluid flow channel in its interior, wherein the receiving unit (12, 112) comprises a closure element (34, 134) which, in a closed position, is designed to fluidically seal the fluid flow channel of the receiving unit (12, 112) between the first end (22) and a second end of the receiving unit (12, 112) opposite the first end (22) with respect to a main flow direction along the fluid flow channel, wherein the closure element (34, 134) is displaceable between the closed position and a release position, wherein the closure element (34, 134) is preloaded into the closed position using a spring element (28), wherein the closure element (34, 134) comprises a substantially cylindrical section (36, 136) which is formed free of perforations, wherein the entire spring element (28), in the release position of the closure element (34, 134), is arranged within a region (80) which, along its entire longitudinal extent, viewed in a radial direction of the cylindrical section (36, 136), is completely overlapped by the cylindrical section (36, 136), wherein the closure element (34, 134) further comprises a partial section (40) provided with perforations (38, 138), wherein the perforations (38, 138) of the partial section (40) are designed as window-like openings (38, 138) which fluidically connect an interior of the closure element (34, 134) to an exterior of the closure element (34, 134), wherein the plug-in unit (14, 114) is designed to be connected at a first end to a further fluid line not belonging to the plug-in unit (14, 114), and which defines a fluid flow channel in its interior, wherein the plug-in unit (14, 114) has a contact surface (74, 82; 153, 182) which is designed to come into contact with a corresponding counter-contact surface (72, 32; 151, 132) of the closure element (34, 134) of the receiving unit (12, 112) so that, as the plug-in unit (14, 114) is progressively inserted into the receiving unit (12, 112), the closure element (34, 134) of the receiving unit (12) is displaced from its closed position in the direction of the release position, wherein a sealing device (46) is arranged on the receiving unit (12, 112) and / or on the plug-in unit (14, 114), said sealing device being designed to act between the receiving unit (12, 112) and the plug-in unit (14, 114) in such a way that the fluid flow channel of the receiving unit (12, 112) and / or the plug-in unit (14, 114) is fluidically sealed to an outside of the coupling device (10, 110), wherein the sealing device (46) is arranged such that a fluidic seal is established between the receiving unit (12, 112) and the plug-in unit (14, 114) before the contact surface (74, 82; 153, 182) of the plug-in unit (14, 114) comes into contact with the counter-contact surface (72, 32; 151, 132) of the closure element, wherein the closure element (34) of the receiving unit (12) has a central bolt (72) which has a free end that extends in the direction of the second end of the receiving unit (12) and which is designed, on insertion of the plug-in unit (14) into the receiving unit (12), in particular with its free end, to bear against a bolt-receiving surface (74) formed on the closure element of the plug-in unit (14), so that on progressively inserting the plug-in unit (14) into the receiving unit (12), wherein the plug-in unit (14, 114) also comprises a closure element (54, 154), the closure element (54) of the plug-in unit (14) or the closure element (34) of the receiving unit (12) is displaced from its closed position toward the release position, characterised in that the counter-contact surface (32; 132) of the closure element (34, 134) of the receiving unit (12, 112) is designed as a collar (32, 132) projecting radially from the closure element of the receiving unit (12, 112).

2. Coupling device (10) according to claim 1, characterised in that the closure element (54, 154) of the plug-in unit (14, 114) is designed, when in a closed position, to fluidically seal the fluid flow channel of the plug-in unit (14, 114) between a second end of the plug-in unit (14, 114) opposite the first end with respect to a main flow direction along the fluid flow channel and the first end, wherein the closure element (54, 154) of the plug-in unit (14, 114) is displaceable between the closed position and a release position, wherein the closure element (54, 154) of the plug-in unit (14, 114) is preloaded into the closed position using a spring element (64, 164).

3. Coupling device (10) according to claim 1 or 2, characterised in that the closure element (54) of the plug-in unit (14) has an increasing diameter in a direction from the second end of the plug-in unit (14) to the first end of the plug-in unit (14).

4. Coupling device (10) according to one of claims 1 to 3, characterised in that a spring force of the spring element (64, 164) that acts on the closure element (54, 154) of the plug-in unit (14, 114) is less, in particular significantly less, than a spring force of the spring element (28) that acts on the closure element (34, 134) of the receiving unit (12, 112), so that on inserting the plug-in unit (14, 114) into the receiving unit (12, 112), the closure element (54, 154) of the plug-in unit (14, 114) is first of all displaced from its closed position to its release position and subsequently, on progressively inserting the plug-in unit (14, 114) into the receiving unit (12, 112), the closure element (34, 134) of the receiving unit (12, 112) is displaced from its closed position to its release position.

5. Coupling device (10) according to one of the preceding claims, characterised in that the spring element (28) is a coiled spring.

6. Coupling device (10) according to one of the preceding claims, characterised in that the spring element (28) is arranged radially outside the cylindrical section (36, 136).

7. Coupling device (10) according to one of the preceding claims, characterised in that the perforations (38, 138) of the partial section (40) are designed as four window-like openings (38, 138).

8. Coupling device (10) according to one of the preceding claims, characterised in that the receiving unit (12, 112) has a housing (16, 116) in which the closure element (34, 134) is accommodated, wherein the housing (16, 116) has a radially inwardly extending projection (30, 130) which is designed to come into contact with the closure element (34, 134), in particular with a sealing element (44, 144) arranged on the closure element (34, 134), in the closed position of said closure element (34, 134).

9. Coupling device (10) according to claim 8, characterised in that the projection (30, 130) is provided with a slanting flank, so that the projection (30, 130) results in a gradually decreasing cross-section of the interior of the housing (16, 116) in a direction from the release position to the closed position of the closure element (34, 134).

10. Coupling device (10) according to claim 8 or 9, characterised in that the housing (16, 116) of the receiving unit (12, 112) is formed in multiple parts, in particular in two parts.

11. Coupling device (10) according to claim 10, characterised in that a first housing part (20, 120), which comprises the first end (22), is fluidically tightly connected to a second housing part (18), which comprises the second end, in particular using a spin welding process or a laser welding process.

12. Coupling device (10) according to one of claims 8 to 11, characterised in that at least one protruding stud (76) is arranged on the housing (16), which is designed to define the release position of the closure element (34) when abutting against the closure element (34).