ROCKER VALVE COMPRISING A SEALING ELEMENT

Abstract

A rocker valve for opening or closing a fluid connection includes a valve chamber into which at least one opening feeds, a pivotally mounted rocker switch, and a membrane surface located between the rocker switch and the opening. By pivoting the rocker switch, the opening can be fluidically opened or closed relative to the valve chamber. The rocker valve further includes a sealing element that is located between the membrane surface and the opening when the rocker switch closes the opening relative to the valve chamber.

Claims

1. A rocker valve for opening or closing a fluid connection, the rocker valve comprising: a valve chamber into which at least one opening feeds, a pivotally mounted rocker switch, a membrane surfacewhich is located between the rocker switch and the opening, wherein the opening to the valve chamber can be opened or closed to fluid by pivoting the rocker switch, and a sealing element, which is located between the membrane surface and the opening when the rocker switchcloses the opening to the valve chamber.

2. The rocker valve according to claim 1, wherein: the sealing element is located as a fluid-tight seal between the membrane surface and the opening when the rocker switch closes the opening to the valve chamber.

3. The rocker valve according to claim 1, wherein: the elasticity and/or toughness of the membrane surface within a temperature range intended for operation of the rocker valve is substantially independent of temperature.

4. The rocker valve according to claim 1, wherein: the elastic modulus, of the membrane surface within a temperature range intended for operation of the rocker valve is substantially independent of temperature.

5. The rocker valve according to claim 1, wherein: within a temperature range intended for operation of the rocker valve (100), the sealing element (170) has a sealing property that is sufficient for the rocker valve (100) application, such that the sealing element (170) is pressed against the opening (120, 130) by pivoting the rocker switch (160), creating a fluid-tight seal.

6. The rocker valve according to claim 1, wherein: the opening is at least one of: a valve inlet; a valve outlet.

7. The rocker valve according to claim 6, wherein: the valve chamber fluidically connects the valve inlet and the valve outlet in an open state of the rocker valve.

8. The rocker valve according to claim 1, comprising: a first opening which represents an inlet to the valve chamber, and a second opening which represents an outlet from the valve chamber, wherein at least one of the openings can be opened or closed by actuating the rocker switch.

9. The rocker valve according to claim 8, wherein: the rocker switch has a first position in which the first opening is open to the valve chamber and in which the second opening is closed to the valve chamber, and a second position in which the first opening is closed to the valve chamber and in which the second opening is open to the valve chamber.

10. The rocker valve according to claim 1, comprising: a first opening which represents an inlet to the valve chamber, a second opening which represents an outlet from the valve chamber, and a third opening which represents a further inlet into the valve chamber, wherein the second opening is open relative to the valve chamber, and the rocker switch has a first position in which the first opening is open to the valve chamber and the third opening is closed to the valve chamber, and a second position in which the first opening is closed to the valve chamber and the third opening is open to the valve chamber.

11. The rocker valve according to claim 1, wherein: the rocker switch is rotatably mounted.

12. The rocker valve according to claim 1, wherein: the rocker switch can be pivoted manually and/or actuated by a motor.

13. The rocker valve according to claim 1, wherein: at least a portion of the valve chamber is laterally bounded by the membrane surface.

14. The rocker valve according to claim 1, wherein: the sealing element is configured such that by pivoting the rocker switch, the sealing element can be pressed onto the opening to form a fluid-tight seal, thereby closing a fluid connection passing through the opening .

15. The rocker valve according to claim 1, comprising at least one of the following features: the sealing element is connected to the membrane surface and is moved along with the membrane surface by the rocker switch; the sealing element surrounds the opening and projects into the valve chamber; the sealing element comprises a first sealing element and a second sealing element, wherein the first sealing element is connected to the membrane surface and is moved along with the membrane surface by the rocker switch, and the second sealing element surrounds the opening and projects into the valve chamber.

16. The rocker valve according to claim 1, wherein: the membrane surface and/or the sealing element is made of or comprises a chemically resistant material.

17. The rocker valve according to claim 1, wherein: the membrane surface comprises a material selected from the group consisting of: PEEK; PTFE; and mixtures or modifications of the aforementioned materials.

18. The rocker valve according to claim 1, wherein: the sealing element comprises a material selected from the group consisting of: an elastic material; a perfluoroelastomer; perfluorinated rubber; FKM; FFKM; a polymer of ethylene, tetrafluoroethylene and perfluoromethylvinylether; and mixtures or modifications of the aforementioned materials.

19. The rocker valve according to claim 1, wherein: the intended temperature range is selected from the group consisting of: a range between -10° C. and 80° C.; a range between 0° C. and 50° C.; and a range between 4° C. and 40° C.

20. A rocker valve for establishing a fluid communication, the rocker valve comprising: a valve inlet and a valve outlet, a valve chamber into which the valve inlet and the valve outlet feed, a pivotally mounted rocker switch, a membrane surface located between the rocker switch and the valve inlet as well as the valve outlet, wherein a fluid connection between the valve inlet and/or the valve outlet and the valve chamber can be opened or closed by pivoting the rocker switch, an inlet sealing element located in a fluid-tight manner between the membrane surface and the valve inlet, when the rocker switch closes the valve inlet to the valve chamber, and an outlet sealing element located in a fluid-tight manner between the membrane surface and the valve outlet, when the rocker switch closes the valve outlet to the valve chamber.

21-22. (canceled)

Description

DESCRIPTION OF THE DRAWINGS

[0038] The invention is further explained below with reference to the drawings, wherein like reference numbers refer to like or functionally-like or similar features.

[0039] FIG. 1 shows a liquid separation system 10 according to embodiments of the present invention, such as, for example, used in HPLC.

[0040] FIGS. 2 to 4 illustrate embodiments of a rocker valve 100.

[0041] FIG. 5 illustrates a plot of hardness versus temperature for various sealing element materials.

[0042] In detail, FIG. 1 shows a general illustration of a liquid separation system 10. A pump 20 receives a mobile phase from a solvent supply 25 via a proportioning device 27. A degasser (not shown) may be used to degas the mobile phase and in this manner reduce the amount of dissolved gases in the mobile phase. The pump 20 impels the mobile phase through a separation device 30 (such as a chromatography column) that comprises a stationary phase. A sample device (or sample injector) 40 may be provided between the pump 20 and the separation device 30 to deliver a sample fluid to the mobile phase. The stationary phase of the separation device 30 is adapted to separate components of the sample fluid. A detector 50 detects separated components of the sample fluid, and a fractionator 60 may be provided for the dispensing of the separated components.

[0043] The mobile phase may comprise only one solvent or a mixture of different solvents. Mixing may be performed at low pressure and upstream of the pump 20, such that the pump 20 is already conveying the mixed solvent as the mobile phase. Alternatively, the pump may comprise individual pump units, wherein each pump unit conveys one solvent or solvent mixture at a time, such that the mixing of the mobile phase (as then seen by the separation device 30) occurs at high pressure and downstream of the pump 20. The composition (mixture) of the mobile phase can be maintained constant over time (isocratic mode) or varied over time in a so-called gradient mode.

[0044] The proportioning device 27 is used to supply one or more solvents to the pump 20 of the liquid separation system 10. For this purpose, the proportioning device 27 comprises one or more rocker valves, such as, for example, shown in FIG. 2 to FIG. 4. Each rocker valve is connected on the input side to one or more solvents and on the output side to an input of the pump 20.

[0045] A data processing unit 70, which may be a conventional personal computer or workstation, may be coupled to one or more of the devices in the liquid separation system 10, as indicated by the dashed arrows, to receive information and/or control the operation of the system or individual components therein. The data processing unit 70 the data processing unit 70 further controls each rocker valve of the proportioning device 27 to selectively supply the pump 20 with one or more solvents.

[0046] FIG. 2A and FIG. 2B show an embodiment of a rocker valve 100, such as, for example, may be used in the proportioning device 27. Whereas FIG. 2A shows the rocker valve 100 in a three-dimensional illustration from the outside, FIG. 2B likewise shows a three-dimensional illustration of a cross-section through the rocker valve 100 shown in FIG. 2A along the line A-A.

[0047] The rocker valve 100 comprises a base plate 110 in which inflows and outflows to the rocker valve 100 may be located. In the embodiment illustrated in FIG. 2, an inlet 120 leads to and an outlet 130 leads away from the rocker valve 100. Inlet 120 and outlet 130 feed into a valve chamber 140, which (in the embodiment shown in FIG. 2) is defined and bounded downwardly by the base plate 110 and upwardly by a membrane 150. The rocker valve 100 furthermore comprises a rocker switch 160 which is rotatably mounted about a bearing 165, such that the rocker switch is pivotal about said bearing 165. For example, the rocker switch 160 can be guided from the (vertical) position V, shown in the FIG. 2, by pivoting to the right into a pivoting position R, as shown schematically, and by way of example, in FIG. 2B.

[0048] The membrane 150 is integrally connected to the rocker switch 160 in the embodiment of FIG. 2. In other embodiments, these rocker switches may be separate and individually formed. The only functionally important aspect is that by actuating the rocker switch 160, the membrane 150 can be actuated with respect to the inlet 120 or the outlet 130.

[0049] As illustrated in FIG. 2B, the rocker valve 100 further comprises a sealing element 170 that is arranged on a membrane surface 180 opposite the inlet 120 and the outlet 130 and which sealing element moves along with this membrane surface 180. In the (vertical) position V of the rocker switch 160, the sealing element 170 presses against the outlet 130 to create a fluid-tight seal and thus closes it (in a fluid-tight manner) to the valve chamber 140, whereas the inlet 130 is open to the valve chamber 140. In this position V, the outlet 130 is thus closed off from the valve chamber 140 and the inlet 120 that is fluidically connected thereto, such that a flow between the inlet 120 and the outlet 130 is inhibited or alternatively the flow path between the inlet 120 and 130 is interrupted.

[0050] By pivoting the rocker switch 160 (to the right in the embodiment of FIG. 2), for example, to the position R, the sealing element 170 is raised relative to the outlet 130 and no longer seals the outlet 130 in a fluid-tight manner, such that a flow path is opened between the inlet 120 and the outlet 130 and whereby a flow between the inlet 120 and the outlet 130 is enabled.

[0051] In this manner, the rocker valve 100 closes the flow path between inlet 120 and outlet 130 in the (switching) position V of the rocker switch 160 and opens it in the (switching) position R of the rocker switch 160. Between these positions V and R, the flow path between inlet 21 and outlet 130 is more or less opened or alternatively closed.

[0052] By separating the sealing element 170 from the membrane 150 (or alternatively from the membrane surface 180), the various functions of the rocker valve 100 can be adjusted and optimized in a targeted manner. The use of the sealing element 170 thus allows an optimization of the sealing function with respect to the outlet 130, whereas the membrane 150 can, for example, be optimized in a targeted manner for longevity with respect to strain brought about by the mechanical load of the rocker switch 160 during switching.

[0053] In one embodiment, the material of the membrane 150 and/or the membrane surface 180 is selected such that the elasticity and/or toughness is substantially independent of temperature within a temperature range intended for operation of the rocker valve 100. Typical temperature ranges may be between -10° C. and 80° C., preferably between 0° C. and 50° C., and further preferably between 4° C. and 40° C.

[0054] In another embodiment, the material of the membrane 150 and/or the membrane surface 180 is selected such that the modulus of elasticity, preferably the complex modulus of elasticity, is substantially independent of temperature or changes only insignificantly within the temperature range intended for operation of the rocker valve 100.

[0055] The material of the sealing element 170 is preferably selected such that within the temperature range intended for operation of the rocker valve 100, it has a sealing property that is sufficient for the rocker valve 100 application, such that the sealing element 170 is pressed against the opening 130 in a fluid-tight sealing manner by pivoting the rocker switch 160 (for example, into the switching position V illustrated in FIG. 2B). The toughness and/or the modulus of elasticity, preferably the complex modulus of elasticity, of the sealing element 170 may thereby exhibit a dependence on temperature within the temperature range intended for operation of the rocker valve, which need not have a negative effect on the sealing functionality.

[0056] The material of the membrane 150 and/or the membrane surface 180 may be or comprise, for example, Teflon, PEEK, PTFE (polytetrafluoroethylene), for example, Moldflon®, as well as mixtures or modifications of these materials.

[0057] The sealing element 170 may consist of or include, for example, an elastic material, a perfluoroelastomer, perfluorinated rubber, FKM, FFKM, ETP®, as well as a mixture or a modification of these materials.

[0058] It is clear that other materials or combinations of materials can be used, depending on the desired application and in particular on the intended temperature range. When using the previously presented materials, the service life of embodiments of the rocker valve 100 could be significantly extended, for example, when used in an extended temperature range (such as below 7° C.), without limiting the sealing functionality.

[0059] In the embodiment illustrated in FIG. 2, the sealing element 170 is used to close or open the outlet 130 to fluid. Accordingly, the sealing element 170 could also act with respect to inlet 120, either closing or opening it to fluid. Alternatively, several sealing elements 170 can also be used, for example, according to the embodiment example in FIG. 2, a first sealing element 170 between the membrane surface 180 and the outlet 130 and a second sealing element 170 between the membrane surface 81 and the inlet 120.

[0060] As an alternative to the embodiment of FIG. 2, in which the sealing element 170 is (fixedly) connected to the membrane surface 180 or attached thereto, the sealing element 170 can also be arranged, for example, in a sealing manner around an opening that feeds into the valve chamber 140 and which can be switchably sealed by the rocker valve 100, such as the inlet 120 or the outlet 130. Accordingly, combinations can also be conceivable. This is shown schematically in FIG. 3. In FIG. 3A, the sealing element 170 is fixedly connected to the membrane surface 180 and is attached to the membrane surface opposite an opening 300 to be sealed, which can be, for example, the inlet 120 or the outlet 130. In FIG. 3B, the sealing element 170 is arranged around the opening 300 in a ring shape and projects into the valve chamber 140. The sealing element 170 may, for example, be fixedly connected to the base plate 110. By pressing the membrane surface 180 against the sealing element 170 (not shown in FIG. 3B), the opening 300 can be sealed in a fluid-tight manner. In FIG. 3C, in addition to the sealing element 170 arranged around the opening 300, as shown in FIG. 3B, another sealing element 310 is provided that is fixedly connected to the membrane surface 180 (corresponding to the sealing element 170 shown in FIG. 3A).

[0061] FIG. 4 illustrate a further embodiment of a rocker valve 100 with one inlet 400 as well as one first outlet 410 and one second outlet 420. The rocker switch 160 is rotatably or alternatively pivotally mounted about a pivot 430. A first sealing element 170A is fitted to the membrane surface 180 opposite the first outlet 410 and is fixedly connected to the membrane surface 180. Similarly, a second sealing element 170B is fitted to the membrane surface 180 opposite the second outlet 420 and is fixedly connected to the membrane surface 180. FIG. 4A shows a first switching state of the rocker valve 100, in which switching state the second sealing element 170B is in sealing engagement against the second outlet 420, allowing flow communication only between the inlet 400 and the first outlet 410. Accordingly, FIG. 4B shows a second switching state of the rocker valve 100, in which switching state the first sealing element 170A is in sealing engagement against the first outlet 410 so that flow communication is only possible between the inlet 400 and the second outlet 420. In this manner, inflow can be directed from the inlet 400 to either the first outlet 410 when in the switch position of FIG. 4A or to the second outlet 420 when in the switch position of FIG. 4B.

[0062] It is clear that by the accesses to the valve chamber 140 identified in FIG. 4 may also be assigned otherwise, for example, reference number 400 could represent an outlet into which, by actuation of rocker switch 160, flow can be selectively directed either from a first inlet (reference number 410) when in the switch position of FIG. 4A or from a second inlet (reference number 420) when in the switch position of FIG. 4B. Further permutations are correspondingly conceivable.

[0063] It is also apparent that embodiments having openings other than those shown in FIG. 3 and FIG. 4 may be used.

[0064] The rocker switch 160 can be actuated either manually, by motor, or, for example, by means of a suitable actuator, as is known in the prior art.

[0065] FIG. 5 represents a plot of hardness (complex modulus of elasticity, Shore hardness or Shore A; ordinate versus temperature (abscissa)) versus temperature for different materials for the sealing element. That which is critical for the application is typically the lower temperature range, for example, between 0° C. and 20° C. Elastomers are typically quite good for sealing. Due to their elasticity, they are easy to actuate and can, for example, provide compensation for tolerances with respect to the second surface when a given contact pressure is applied to the sealing surface. The sealing effect can thus be enhanced. However, since strong acids and alkalis are also used in HPLC and, in addition, swelling of the material could lead to undesirable side effects such as solvent carryover or destruction of the underlying actuator, fluoroelastomers are particularly suitable for this purpose, with FFKM showing a particularly high chemical suitability. However, FFKM shows a lower suitability with regard to low temperatures (unchanging flexibility of the material).