DE102016108103A1 - Compensation of volume artifacts when switching a fluid valve - Google Patents

Abstract

A fluid valve (100) for controlling a working fluid (102), wherein the fluid valve (100) comprises a closing device (104) having a first closing part (110) in a working volume (116) of the working fluid (102) and a second closing part (112), which is separated from the working fluid (102) and the first closing part (110) by a space separating device (106) and is configured such that the second closing part (112) opens and / or closes the fluid valve (100) onto the first closing part (110). 110) through the room divider (106), and compensating means (108) arranged to adjust an auxiliary volume temporarily provided to the working fluid (102) by the room divider (106) upon opening and / or closing by modifying the working fluid ( 102) at least partially compensate for opening and / or closing available working volume (116).

Description

TECHNICAL BACKGROUND

 The present invention relates to a fluid valve, a fluid pump, a method of controlling a working fluid, and a sample separator and a use.

In an HPLC, a liquid (mobile phase) is typically run at a very precisely controlled flow rate (for example in the range of microliters to milliliters per minute) and at a high pressure (typically 20 to 1000 bar and beyond, currently up to 2000 bar). , in which the compressibility of the liquid can be felt, by a so-called stationary phase (for example, in a chromatographic column), moved to separate individual components of a sample liquid introduced into the mobile phase from each other. Such an HPLC system is known, for example from the EP 0,309,596 B1 same Applicant, Agilent Technologies, Inc.

 Such an HPLC system often has a fluid pump with one or more pistons reciprocating in a piston chamber, which cooperate with one or more intake valves. When switching the intake valves, inaccuracies may occur with respect to the pumped fluid.

EPIPHANY

 It is an object of the invention to enable pumping of a fluid with high precision. The object is achieved by means of the independent claims. Further embodiments are shown in the dependent claims.

 According to an exemplary embodiment of the present invention, a fluid valve (ie, a valve for controlling fluid, wherein a fluid may be a gas and / or a liquid, optionally comprising solid particles) is for controlling a working fluid (especially a mobile phase, more particularly one) Solvent or a solvent composition), the fluid valve having a closing device with a first closing part in a working volume of the working fluid (in particular in contact with the working fluid) and with a second closing part that is separated by a space separating device (in particular a space separating membrane) from the working fluid and the first Closing part is separated (in particular out of contact with the working fluid standing) and is formed such that the second closing part for opening and / or closing the fluid valve acts on the first closing part through the space separating device, and a Kompensat Ioneinrichtung has, which is adapted to the working fluid by the space separating device during opening and / or closing temporarily provided (in particular positive or negative) additional volume by temporary modification (especially temporary reduction or increase in opening and / or closing) of the working fluid during opening and / or Closing available work volume to compensate at least partially (clearly, especially when closing the room can be larger, and therefore the volume can be reduced according to an embodiment of the invention).

 According to another exemplary embodiment, there is provided a fluid pump for pumping a working fluid, the fluid pump having a piston recirculating in a piston chamber for conveying the working fluid and a fluid valve having the above-described features arranged upstream of the piston chamber as an inlet valve for the working fluid ,

 According to yet another exemplary embodiment, there is provided a sample separator for separating a fluidic sample, the sample separator having a fluid pump with a fluid valve having the above-described features, the fluid pump for pumping a mobile phase being formed as working fluid, and a sample separator for separating the fluid Having introduced into the mobile phase fluidic sample.

According to yet another exemplary embodiment, there is provided a method of controlling a working fluid to be pumped, wherein in the method, working fluid is provided in a working space of a fluid valve in which a first closing means of the fluid valve is disposed on the first closing part by means of a second closing part Room separation device between the working space and another space of the fluid valve is acted through, in which other space the second closing part is arranged such that due to the action, the fluid valve opens or closes and when opening or closing the space separator the working fluid in the working space temporarily (in particular positive, alternatively negative) additional volume provides, and the additional volume is at least partially compensated to thereby provide the working fluid when opening or closing made available or standing working volume temporarily to modify (in particular to reduce). Clearly, when opening or closing an available volume can be kept as constant as possible or that by switching resulting (especially positive or negative) additional volume can be reduced.

 According to another exemplary embodiment, a fluid valve having the features described above is used in supercritical liquid chromatography.

 According to an exemplary embodiment of the invention, full or partial volume compensation for at least partially compensating artifacts when switching a fluid valve may be performed to increase the precision of the delivered amount of working fluid. Exemplary exemplary embodiments of the invention address the problem that when a fluid valve is switched, a mechanical component of the fluid valve can move jerkily and can exert a force that displaces this on an elastic or flexible space separating device (such as a space separating membrane). As a result of this brief spatial displacement or deformation of the room separating device, the working fluid is provided with an artificial additional volume (in particular positive, but in certain configurations also negative) to the working volume during the switching process. Especially in the case of a positive additional volume, an undesirable negative pressure can occur or outgassing of the working fluid take place, which is particularly undesirable. This conventionally leads to an undefinedness of the fluid quantity conveyed through the fluid valve and can therefore undesirably impair the precision and reproducibility of the conveying and switching process. The described phenomena can lead to instantaneous outgassing of the working fluid or, in the aftermath, also to undesirable hydrodynamic pressure oscillations or other artifacts. An exemplary embodiment of the invention reduces this uncertainty and thus increases the precision of the conveying and switching process by compensating with a compensation device, the instantaneous additional volume as Schaltartefakt preferably at any time during the switching cycle, i. reduced or even eliminated. Clearly, a volume of compensation can be temporarily contributed to the working volume at the occurrence of the Schaltartefakts to counteract the volume impairment by the Schaltartefakt or to compensate for this in whole or in part. "Upon the occurrence of the Schaltartefakts" this can include on the one hand that an artifact has occurred or is currently occurring, so that a compensation can be initiated as a reaction. On the other hand, "when the switching artifact" occurs, this can mean that an artifact is to be expected (for example from experience), so that a compensation can be initiated as a proaction.

 Hereinafter, additional embodiments of the fluid valve, the fluid pump, the method for controlling a working fluid, as well as the sample separation device and the use will be described.

 Advantageously, a space separating membrane of the space separating device can have a central area (in which the closing parts are operatively coupled with each other) with a higher elasticity than another elasticity in an edge area surrounding the central area. In other words, for a given force, the central area may experience a greater deflection than the edge area. Then the central region can accomplish a force transmission between the two closing parts with little resistance, whereas the edge region then shows only a small inclination to generate an artificial additional volume during a switching process.

 According to one embodiment, the compensation device may comprise a compensation fluid in a compensation space, in which the second closing part is arranged and which adjoins the space separating device. The compensation fluid counteracts (due to its low compressibility or due to the constant volume of the compensation fluid) the emergence of the additional volume during switching. The compensation fluid and the working fluid can thus be in pressure exchange with one another via the space separation membrane (and optionally by a compensation membrane described in more detail below), but remain separated from one another by the at least one membrane.

 According to one embodiment, the compensation fluid may be an incompressible compensation fluid, in particular a liquid or a gel. It is thus particularly advantageous to design the compensation fluid incompressibly or with low compressibility, since the influence of the compensation fluid (desired mode of action) which counteracts the switching artefact is then particularly strong. For example, the compensation fluid may be oil.

According to one embodiment, the compensation device may have an (additional) compensation membrane between the working volume with the first closing part and a compensation space in which the second closing part is arranged. Thus, in addition to the space separating device, which is preferably designed as a space separating membrane, it is additionally possible to provide a compensation membrane which can or should be hydraulically or pneumatically coupled to the membrane of the room separating device by means of a compensating fluid in the compensation space. A space separating membrane of the room divider shifting pressure surge when switching the fluid valve can then be transferred to the compensation membrane via the working fluid ("outward") and with sign reversal via the compensation fluid "inward" (ie a pressure surge on the space separation membrane causes a vacuum surge on the compensation membrane), one to the shift the membrane of the room divider inversely affects the working volume. In other words, the compensation membrane then reduces the working volume increased by the displacement of the membrane of the space divider (preferably by the same amount).

 According to one exemplary embodiment, the compensation membrane can be set up to at least partially compensate for the additional volume of the working fluid temporarily generated by the room separating device during opening and / or closing by compensating movement of the compensation membrane. When the fluid valve is switched, the working volume is temporarily increased (or degraded if configured accordingly), thus causing an increased (or reduced) penetration of the membrane of the room divider into the compensation space, which, however, results in a temporary reduced (or increased) displacement of the compensation membrane for compensation purposes into the working volume or the working space of the working fluid leads. By such a coupling, the undesirable effect of changing the working volume when switching the fluid valve is fully or partially compensated.

 According to one embodiment, the compensating means may comprise a rocking mechanism operable by the room divider or the closing members when closing and acting in response to the working volume to at least partially equalize the additional volume. Such a rocker can couple two mechanical elements or action points (for example, body) via a rotatably suspended lever arm. If one of the two mechanical elements or action points is deflected during the switching of the fluid valve due to the artifact described under temporary enlargement (or reduction) of the working volume, the rocking mechanism can cause the other of the two mechanical body or the like (mediated via the rotatable lever arm) back teeters and thereby the working volume in a corresponding manner, eg by means of the compensation membrane, reduced (or increased). As soon as the influence on the first mechanical body or the like ends as a result of the switching operation, the rocker moves back to the initial state. This also deactivates the compensating temporary modification of the working volume by the other of the two mechanical bodies or the like.

 According to one embodiment, the compensation device can be designed to completely compensate the additional working volume. This leads to a particularly precise switching and conveying function of the fluid valve or the fluid pump.

According to one embodiment, the fluid valve may be formed as an actively switchable fluid valve. In other words, the switching of the fluid valve can be effected by a predefinable control signal, for example by an electrical signal. With such a control signal, for example, a magnetic coil can be selectively energized or a current can be inverted or even omitted or disabled, whereby a magnetic mechanism can cause a corresponding movement of the second closing part, which acts through the space separating device on the first closing part. Instead of a magnetic mechanism, for example, a spring mechanism or another functionally corresponding mechanism can be used.

 According to one embodiment, the closing device and the compensating device may be designed to effect at least partial compensation in the transition between an opening state and a closing state of the fluid valve. It has been found that the above-described artifact occurs or acts particularly strongly in the rapid (dynamic) transition from an open state to a closed state of the fluid valve (outgassing of the working part, or formation of a gas bubble). The compensation described is therefore particularly effective in this switching process. Alternatively or additionally, however, it is also possible to implement a corresponding compensation when an artifact occurs during the transition from a closed state to an open state of the fluid valve.

 According to one embodiment, the space separating device may be an at least partially flexible space separating device, in particular a membrane. Such a membrane may preferably move elastically upon mechanical impact, i. after releasing a mechanical action reversibly move back to its original state. Such a membrane may preferably be designed to be fluid-tight in order to prevent unwanted leakage of working fluid toward the second closing part or into the compensation volume.

According to one exemplary embodiment, the first closing part may have a closing body arranged in a seat in the closed state, in particular a closing body Closing ball, exhibit. If the closing body is in the seat, the fluid valve is closed. If the closing body (possibly under the influence of the closing parts) moves out of the seat, the fluid valve is opened and allows the working fluid to flow between the seat and closing body.

 According to one embodiment, the closing body may be arranged in a biased state, in particular in a state biased by a spring in the seat. The fluid valve can therefore be biased by a mechanical spring. However, the second closing part can act on the first closing part through the space separating device in such a way that the first closing part presses the closing body out of the seat against its bias and thus enables a flow of working fluid between closing body and seat.

According to one embodiment, the first closing part may have a coupling body, which is designed to act on the closing body and can be actuated via the space separating device by means of the second closing part. Such a coupling body may be a piston-like rigid body, which is mediated by the flexible membrane of the room divider also axially displaced by axial displacement of an actuator of the second closing member and thereby selectively pushes the closing body out of the seat or not (similar to US 4,911,405 shown).

 According to one embodiment, the second closure member may include an actuator biased into a fluid valve closing or opening condition. The bias voltage can for example also be effected by means of a further spring, which presses the second closing part through the space separating device against the first closing part. In one configuration, in the absence of a control signal applied to the actuator, the further spring (or other further biasing member) may urge the second closure member against the first closure member through the space divider, the first closure member in turn pushing the biased closure body out of the seat and thus flow of the working fluid through the then opened fluid valve allowed therethrough. In the presence of a control signal acting on the actuator, the second closing part can be withdrawn against the biasing force of the further biasing element, so that the second closing part no longer presses against the first closing part. As a result, the first closing part does not push the pretensioned closing body out of the seat. As a result, the bias of the closing body causes the closing body is pressed against the seat and thus no flow of the working fluid through the then closed fluid valve is made possible.

 According to one embodiment, the second closing part can be actuated by switching on or off an electrical signal, so that an action of the actuator on the first closing part is activated or deactivated. The application of an electrical signal may, for example, generate a magnetic field which then applies a corresponding magnetic force to a magnetic actuator, or it may be an electrical voltage which is applied via e.g. a piezoelectric element causes the deflection.

 According to one embodiment, the separation device can be designed as a chromatographic separation device, in particular as a chromatography separation column. In a chromatographic separation, the chromatographic separation column may be provided with an adsorption medium. At this, the fluidic sample can be stopped and only then with appropriate eluent (isocratic) or in the presence of a specific solvent composition (gradient) fractionally detached again, thus the separation of the sample is accomplished in their fractions.

 The sample separation device may be a microfluidic measuring device, a life science device, a liquid chromatography device, a high performance liquid chromatography (HPLC), an UHPLC device, an SFC (Supercritical Liquid Chromatography) device, a gas chromatography device, an electrochromatography device, and / or a gel electrophoresis device , However, many other applications are possible.

 For example, the fluid pump may be configured to convey the mobile phase through the system at a high pressure, for example, from a few hundred bars up to 1000 bars or more.

 The sample separator may include a sample injector for introducing the sample into the fluidic separation path. Such a sample injector may comprise a syringe-dockable injection needle in a corresponding fluid path, which needle may be withdrawn from that seat to receive sample, wherein upon reintroduction of the needle into the seat, the sample is in a fluid path which, for Example, by switching a valve, can be switched into the separation path of the system, which leads to the introduction of the sample in the fluidic separation path.

The sample separator may include a fraction collector for collecting the separated components. Such a fraction collector may contain the various components for example in lead different liquid container. The analyzed sample can also be fed to a drain tank.

 Preferably, the sample separation device may comprise a detector for detecting the separated components. Such a detector may generate a signal which can be observed and / or recorded and which is indicative of the presence and amount of sample components in the fluid flowing through the system.

BRIEF DESCRIPTION OF THE FIGURES

 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 particular description of embodiments taken in conjunction with the accompanying drawings. Features that are substantially or functionally the same or similar are given the same reference numerals.

1 shows an HPLC system according to an exemplary embodiment of the invention.

2 shows a fluid valve of a fluid pump according to an exemplary embodiment of the invention.

3 shows a fluid valve of a fluid pump according to another exemplary embodiment of the invention.

4 shows a fluid valve of a fluid pump according to yet another exemplary embodiment of the invention.

5 shows a portion of a fluid valve of a fluid pump according to yet another exemplary embodiment of the invention.

6 and 7 show a conventional fluid valve in different operating conditions.

The illustration in the drawings is schematic.

Before describing exemplary embodiments with reference to the figures, some basic considerations will be summarized based on which exemplary embodiments of the invention have been derived.

 According to an exemplary embodiment of the invention, an externally activatable motion compensated fluid valve is provided to suppress, during the switching operation in a fluid-working fluid space, an artificial volume change, in particular, to bring it to a net zero value.

 The aim of a corresponding mechanism is to avoid an excessive positive or negative pressure on an input line as well as oscillations or fluctuations of the working flow when an active inlet valve of a fluid supply path is switched. A motion compensation according to an exemplary embodiment has the advantage that, in contrast to a fluidic damping, the motion compensation has no undesirable influence on the accuracy of an associated flow rate. If a suction stroke is proportioned, using motion compensation will also not affect the solvent composition.

 Conventional intake valves of fluid supply systems in which the actuator is located externally (ie, separate from the working fluid), particularly in a fluid pump of a sample separator suffer from the intrinsic problem that a diaphragm of the fluid valve undergoes a volumetric displacement when the valve is switched. Corresponding artifacts are particularly pronounced when a solenoid is activated to close the fluid valve to attract an anchor. Then, a sudden backward movement of the membrane occurs which creates a spike in the vacuum.

 The phenomena described lead to problems. It is in fact necessary to isolate dry mechanical parts of the valve which come into contact with the working fluid from each other. At the same time, however, a well controllable movement is necessary, which favors the implementation of a preferably elastic membrane as a space separating device. Omitting a space separating device (in particular a membrane) is not easily possible for this reason. Even a membrane with a relatively large diameter is advantageous, so that it has a sufficiently long lifetime. However, such a membrane, which can survive, for example, 100,000,000 cycles, causes a particularly significant change in volume even with short strokes.

Regarding the elasticity of the membrane, the following considerations are relevant. For portioning in the context of a gradient mode, a rigid membrane would be advantageous since any resiliency entails uncertainty in the proportioned volumes trapped as packets between a primary metering piston and a gradient form solvent selector. Therefore, an elastic membrane with an influence on the precision of the dosed Solvent packages accompanied. An elastic membrane is also susceptible to property changes depending on the pressure difference across the membrane. The membrane also causes considerable volume in the presence of external pressure, which is particularly problematic in low pressure proportioning systems. An elastic membrane thus plays a significant role in influencing the gradient composition by the liquid level in liquid containers. Many mechanisms, including pressure-modulated system elasticity, pressure modulated resonant frequency of fluid oscillations in conduits, pressure modulated excessive trapping volumes across the diaphragm, and pressure modulated operating times of the valve are to be mentioned in this context.

 For a given membrane, it is also not easily possible to introduce a very small path of movement (distance). On the one hand, this is due to the tolerance of the components involved. But a certain distance is doubly negative, on the one hand about the deflection on the moving absolute volume and on the other hand because of the speed of the volume change, caused by an anchor, which is accelerated over the movement path.

 Further considerations regarding the speed of the movement relate to a physical or technical limitation of coil drives (in traction mode). As the current through the coil increases, at some point the armature will begin to move against a bias of a spring. As the piston moves, a reduction in a magnetic gap occurs. This leads to even stronger driving forces and disproportionate acceleration of the armature.

 In view of the above-described technical problems and the framework discussed below, exemplary embodiments of the invention are based on the idea of suppressing or eliminating the undesirable volumetric effects of diaphragm movement when a fluid valve is switched by a compensation mechanism.

 Furthermore, a hermetically sealed, completely liquid-filled chamber is assumed, in which an armature controlled by means of a coil moves. The membrane provides a boundary to the solvent carrying parts of the fluid valve. In this way it can be achieved that the movement of the located in the closed space on the coil side of the membrane does not change the volume under the membrane. Consequently, there is also no volume change above the membrane (i.e., in the solvent carrying portion of the fluid valve). However, the mechanical parts can move without changing the total volume of each of the chambers. For example, while the center of the diaphragm performs the axial movement necessary for the operation of a movable pin of the first closure member, the compensation fluid in the sealed chamber will force the edge portions of the diaphragm to move in a direction such that the total volume of working fluid on the suction conduit preserved. At this point it should be explained that - when the central region of the membrane is retracted or pushed (as by a spring arrangement on the first closing element) - the compensation liquid is displaced, which makes place by the bulging (ie pushing out) of the edge regions of the membrane , If, for example, the center of the membrane is advanced (ie pushed out) (as by a spring arrangement on the second closure element or by the action of the armature), then the edge regions of the membrane under the effect of the atmospheric pressure, the pressure of the working fluid or the elasticity of the membrane into it (ie towards the compensation liquid). The compensation fluid provides for the invariance of the volumes of the working and compensation chamber.

 Because the volume of the compensation liquid on the side of the membrane on which the second closure member is located is constant due to the incompressibility of liquids at moderate pressures (regardless of the position of the piston), rapid movement of the anchor does not result in separation through the membrane volumes. In this way, pressure peaks are suppressed.

 Due to the supporting effect of the compensation liquid on the underside of the membrane (ie in the compensation chamber), an active inlet valve can be created, which is also robust against external pressures. Such a valve can also be used in SFC (Supercritical Liquid Chromatography) applications with liquid carbon dioxide.

 According to an exemplary embodiment, hydraulic damping may also be introduced. This can be accomplished, for example, by a volume of liquid below the anchor which, together with a sufficiently high restriction, is capable of inhibiting too fast movement of the anchor. Such a construction can be realized inside or in the environment (column with body).

According to an exemplary embodiment, the membrane may be integrally formed. It can be provided with a wave profile (see for example 4 ). It is possible to implement a single membrane or a plurality of membranes (for example two, see 5 ). In the latter case, a membrane for the transmission of movement and the other membrane can be used for volume compensation.

 According to an exemplary embodiment, the space separating device may be formed instead of a membrane, for example, as a force transmitting body passing through a fluidic seal.

 According to one exemplary embodiment of the invention, the compensation device, in particular a compensation fluid, can be designed to keep the volume above the membrane constant. Such a compensation fluid may also be designed to slow down the membrane movement. Clearly, the compensation device can thus also be designed as a viscous brake.

 If the working fluid is under an overpressure, the compensation liquid can also be under an overpressure, for example in the range between 5 bar and 80 bar, in particular approximately equal to the pressure of the working fluid.

1 shows the basic structure of an HPLC system as an example of a sample separator 10 , as it can be used for example for liquid chromatography. A fluid pump 20 as a fluid drive device with solvents from a supply unit 25 supplied drives a mobile phase through a separator 30 (such as a chromatographic column) containing a stationary phase. A degasser 27 can degas the solvents before these the fluid pump 20 be supplied. A sample application unit 40 with a switching valve 95 is between the fluid pump 20 and the separator 30 arranged to introduce a sample liquid in the fluidic separation path. The stationary phase of the separator 30 is intended to separate components of the sample. A detector, see flow cell 50 , detects separated components of the sample, and a fractionator may be provided to dispense separated components of the sample into dedicated containers. Liquids no longer needed can drain into a drain 60 be issued.

A control unit 70 controls the individual components 20 . 25 . 27 . 30 . 40 . 50 . 60 . 95 of the sample separator 10 ,

In the fluid pump 20 can have at least one piston chamber 88 be provided, in which a piston 86 to recirculate fluid. Often there are several pistons 86 and associated piston chambers 88 intended. Upstream of at least one of the piston chambers 88 may be a respective fluid valve 100 be arranged as an inlet valve, which selectively allows or prevents the fluid flow. Exemplary embodiments of the invention for such inlet or fluid valves 100 will be further referring to 2 to 5 described. A detail 84 the fluid pump 20 in 1 shows one in a piston chamber 88 Reciprocatable (see double arrow) arranged piston 86 to promote mobile phase as working fluid. A fluid valve 100 according to an embodiment of the invention, for in 2 to 5 possible embodiments are shown, is upstream of the piston chamber 88 arranged.

2 shows a fluid valve 100 a fluid pump 20 according to an exemplary embodiment of the invention.

Such a fluid pump 20 serves to pump a solvent or a solvent composition as a working fluid 102 in a workroom or work volume 116 , in which, for example, a pressure of <20 bar prevails. The fluid pump 20 has an in 2 not shown, in a piston chamber 88 Reciprocating arranged piston 86 for conveying the working fluid 102 on. This per se known piston-piston chamber arrangement is according to 2 arranged at a position indicated by an arrow 170 is marked. The fluid valve 100 is thus upstream (where a flow direction by an arrow 172 indicating a valve inlet, and the other arrow 170 indicative of a valve outlet) of the piston chamber 88 arranged and as a pump inlet valve for the working fluid 102 educated. The pump inlet valve controls the flow of the working fluid, allowing inflow of the working fluid 102 into the piston chamber either to (open valve position) or not (closed valve position).

This in 2 illustrated fluid valve 100 for controlling the working fluid 102 has an active locking device 104 with a first closing part 110 in a working volume 116 of the working fluid 102 and a second closing part 112 on. The second closing part 112 is by a trained as a flexible, flüssigkeitsimpermeable room separation membrane space separating device 106 from the working fluid 102 and the first closing part 110 separated. Furthermore, the second closing part 112 formed such that the second closing part 112 for opening and / or closing the fluid valve 100 on the first closing part 110 over the room divider 106 acting under membrane movement.

In the fluid valve 100 is also a compensation device 108 provided, which is set to the working fluid 102 through the Space separator 106 when closing temporarily additionally provided additional volume by reducing the working fluid 102 when closing available work volume 116 to compensate for the most part. The compensation device 108 has a compensating fluid designed as an incompressible fluid 118 within a compensation space 120 on, in which the second closing part 112 is arranged. A through the compensation room 120 delimited volume is adjacent to the room divider 106 at. Thus, the room divider separates 106 the volume of work 116 with the working fluid 102 fluidly from the compensation space 120 with the compensation fluid 118 , At the same time, the room divider connects 106 the volume of work 116 with the working fluid 102 in terms of pressure and volume with the compensation space 120 with the compensation fluid 118 ,

In the fluid valve 100 acting as an actively switchable fluid valve 100 is formed, performs a switching of the in 2 shown opening state in a closed state (not shown), although also to a pressure on the membrane designed as a space separating device 106 , By a resulting back pressure, the incompressible compensation fluid 118 exerts on the membrane from the bottom, but it comes as a result to no significant unwanted extra volume by the membrane movement when switching. The locking device 104 and the compensation device 108 are thus formed, a volume compensation at the transition between an open state and a closed state of the fluid valve 100 to accomplish.

Out 2 It can also be seen that the first closing part 110 in the closed state of the fluid valve 100 in a seat 120 arranged closing body 122 in the form of a closing ball (for example made of ruby). Above the closing body 122 where the piston chamber 88 and the piston 86 located (not shown), a high pressure of, for example, 1000 bar prevail. The closing body 122 is in one by means of a spring 124 prestressed state sealing in the seat 120 stored. In other words, there is the closing body 122 in the seat 120 and does not allow transfer of working fluid 102 between closing body 122 and seat 120 if no external force on the closing body 122 acts.

The inside of the work space or work volume 116 arranged first closing part 110 moreover has a piston-like coupling body 126 on, acting on the closing body 122 by axial process of the coupling body 126 trained and through the flexible room divider 106 away by means of the force-coupled second Verschließteils 112 is operable. The coupling body 126 has a head-side pin 180 for direct action on the closing body 122 and an underside anvil 182 acting as a driver and through the room divider 106 through by an actuator also referred to as anchor 128 can be moved. For this purpose, this points in the compensation space 120 beyond the space separating device designed as a membrane 106 arranged second closing part 112 the actuator 128 on, in a the fluid valve 100 opening state is biased. The bias of the actuator 128 is configured to be another spring 184 the actuator 128 according to 2 pushes up and thus the closing body 122 out of the seat 120 pushes out into an open state. The second closing part 112 is actuated by applying an electrical signal, so that the previously biased actuator 128 then not on the first closing part 110 acts.

By applying such an electrical signal, a coil 190 be activated to generate a magnetic field. This can be on the actuator 128 acting in the manner described and the actuator according to 2 pull down.

With the operation of the fluid valve 100 according to 2 Thus, a method for controlling working fluid 102 be carried out at the working fluid 102 in the workroom 116 of the fluid valve 100 flows. In the workroom 116 is the first closing part 110 of the fluid valve 100 arranged. Then on the first closing part 110 by means of the second closing part 112 through the room divider 106 between the workspace 116 and the compensation room 120 of the fluid valve 100 be acted upon so that due to the action of the fluid valve 100 opens or closes. Especially when closing the room divider 106 the working fluid 102 in the workroom 116 provide an initially undesirable additional volume in itself. In the compensation room 120 is the second closing part 112 arranged. The additional volume is (in particular before or when it occurs) by means of the compensation device 108 compensated thereby to the working fluid 102 when closing additionally available working volume 116 to reduce or compensate.

The compensation room 120 is complete with a liquid as a compensation fluid 118 filled and hermetically sealed. This closed system causes a movement of the second closing part 112 the fluid pump 100 does not lead to a change in the liquid volume. Instead, the compensation fluid 118 forced to get around the anchor of the second closing part 112 to move around.

3 shows a fluid valve 100 a fluid pump 20 according to another exemplary embodiment of the invention. As shown with a dashed circle is according to 3 a hydraulic damping device 300 implemented as the liquid volume inside the second closing part 112 is designed. As a result, a viscous brake can be formed, which preferably offers a sufficiently high fluidic restriction, so that too rapid a movement is inhibited or inhibited.

4 shows a fluid valve 100 a fluid pump 20 according to yet another exemplary embodiment of the invention. In addition to the hydraulic damping device 300 is according to 4 the room divider 106 designed as a wave-shaped membrane. This makes it easier to realize the functions of motion transmission and volume balance.

5 shows a portion of a fluid valve 100 a fluid pump 20 according to another exemplary embodiment of the invention.

According to 5 has the compensation device 108 a compensation membrane 500 between the work volume 116 and the compensation room 120 on, in which the second closing part 112 is arranged. The compensation membrane 500 is set up when closing the valve by the room divider 106 artificially generated additional volume V1 of the working fluid 102 by a compensation movement of the compensation membrane 500 preferably completely compensate, see compensation volume V2 = V1. In order to achieve this compensating effect, the space separating device designed as a space separating membrane is 106 with the compensation membrane 500 via a fluid connection 502 hydraulically coupled.

6 and 7 show a conventional fluid valve 600 in different operating states.

According to 6 a magnet is de-energized and the fluid valve 600 open, so working fluids 602 at from an inlet 604 to an outlet 606 can flow. With an arrow 610 is indicated that there is a gap between ball and seat, through which the working fluid 602 can flow through it. A part 620 shows the stop of the pin.

According to 7 the magnet is energized and the fluid valve 600 closed. reference numeral 700 indicates that the ball is now sealingly seated. A gap is with reference numerals 710 indicated. According to 6 and 7 it comes when switching the fluid valve 600 to pressure artifacts that can negatively impact the flow rate constancy and other pumping characteristics.

 It should be noted that the term "comprising" does not exclude other elements and that the "on" does not exclude a plurality. Also, elements described in connection with different embodiments may be combined. It should also be noted that reference signs in the claims should not be construed as limiting the scope of the claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0309596 B1 [0002]
• US 4911405 [0024]

Claims (20)

Fluid valve ( 100 ) for controlling a working fluid ( 102 ), wherein the fluid valve ( 100 ) comprises: a locking device ( 104 ) with a first closing part ( 110 ) in a working volume ( 116 ) of the working fluid ( 102 ) and with a second closing part ( 112 ) separated by a room divider ( 106 ) of the working fluid ( 102 ) and the first closing part ( 110 ) is separated and is formed such that the second closing part ( 112 ) for opening and / or closing the fluid valve ( 100 ) on the first closing part ( 110 ) via the room divider ( 106 ) acts; a compensation device ( 108 ), which is set up, the working fluid ( 102 ) through the room separation device ( 106 ) temporarily opened additional volume (V1) upon opening and / or closing by modifying the working fluid ( 102 ) when opening and / or closing the available work volume ( 116 ) at least partially compensate. Fluid valve ( 100 ) according to claim 1, wherein the compensation device ( 108 ) a compensation fluid ( 118 ) in a compensation room ( 120 ), in which the second closing part ( 112 ) and that to the room separation device ( 106 ) adjoins. Fluid valve ( 100 ) according to claim 2, wherein the compensation fluid ( 118 ) a substantially incompressible compensation fluid ( 118 ), in particular one selected from the group consisting of a liquid, a gel and granules. Fluid valve ( 100 ) according to one of claims 1 to 3, wherein the compensation device ( 108 ) a compensation membrane ( 500 ) between the working volume ( 116 ) and a compensation room ( 120 ), in which the second closing part ( 112 ) is arranged. Fluid valve ( 100 ) according to claim 4, wherein the compensation membrane ( 500 ) is set up, when opening and / or closing by the room separation device ( 106 ) temporarily generated additional volume of the working fluid ( 102 ) by a compensation movement of the compensation membrane ( 500 ) at least partially compensate. Fluid valve ( 100 ) according to one of claims 1 to 5, wherein the compensation device ( 108 ) has a rocking mechanism which is accessible from the room divider ( 106 ) is operable when closing and in response to the working volume ( 116 ) acts to at least partially offset the additional volume. Fluid valve ( 100 ) according to one of claims 1 to 6, wherein the compensation device ( 108 ) is designed to completely compensate for the additional volume. Fluid valve ( 100 ) according to one of claims 1 to 7, designed as an actively switchable fluid valve ( 100 ). Fluid valve ( 100 ) according to one of claims 1 to 8, wherein the locking device ( 104 ) and the compensation device ( 108 ) are at least partially compensated by modifying the working fluid ( 102 ) when opening and / or closing the available work volume ( 116 ) at the transition between an opening state and a closing state of the fluid valve ( 100 ) to accomplish. Fluid valve ( 100 ) according to one of claims 1 to 9, wherein the space separating device ( 106 ) an at least partially flexible or elastic space separating device ( 106 ), in particular a membrane, more particularly a wave-shaped membrane. Fluid valve ( 100 ) according to one of claims 1 to 10, wherein the first closing part ( 110 ) one in the closed state in a seat ( 120 ) arranged closing body ( 122 ), in particular a closing ball. Fluid valve ( 100 ) according to claim 11, wherein the closing body ( 122 ) in a prestressed state, in particular by means of a spring ( 124 ) prestressed condition, in the seat ( 120 ), wherein in particular the first closing part ( 110 ) a coupling body ( 126 ), which acts on the closing body ( 122 ) and by the space separating device ( 106 ) by means of the second Verschließteils ( 112 ) is operable. Fluid valve ( 100 ) according to one of claims 1 to 12, wherein the second closing part ( 112 ) an actuator ( 128 ), which in one the fluid valve ( 100 ) closing or opening state is biased. Fluid valve ( 100 ) according to claim 13, wherein the second closing part ( 112 ) can be actuated by switching on, reversing or switching off an electrical signal, so that an action of the actuator ( 128 ) on the first closing part ( 110 ) is activated or deactivated. Fluid valve ( 100 ) according to one of claims 1 to 14, wherein the compensation device ( 108 ) a hydraulic damping device ( 300 ), in particular designed as Liquid-filled cavity in and / or on the second closing part ( 112 ). Fluid pump ( 20 ) for pumping a working fluid ( 102 ), wherein the fluid pump ( 20 ): one in a piston chamber ( 88 ) reciprocally arranged pistons ( 86 ) for conveying the working fluid ( 102 ); a fluid valve ( 100 ) according to one of claims 1 to 15, which upstream of the piston chamber ( 88 ) arranged as an inlet valve for the working fluid ( 102 ) is trained. Sample Separator ( 10 ) for separating a fluidic sample, wherein the sample separation device ( 10 ) comprises: a fluid pump ( 20 ) with a fluid valve ( 100 ) according to one of claims 1 to 15, wherein the fluid pump ( 20 ) for pumping a mobile phase as working fluid ( 102 ) is trained; a sample separator ( 30 ) for separating the fluidic sample introduced into the mobile phase. Sample Separator ( 10 ) according to claim 17, further comprising at least one of the following features: the sample separation device ( 30 ) is designed as a chromatographic separation device, in particular as a chromatography separation column; the sample separator ( 10 ) is configured to analyze at least one physical, chemical and / or biological parameter of at least one fraction of the fluidic sample; the sample separator ( 10 ) comprises at least one of the group consisting of a detector device, a chemical, biological and / or pharmaceutical analysis device, a liquid chromatography device and an HPLC device; the sample separator ( 10 ) is designed for use in supercritical liquid chromatography; the fluid pump ( 20 ) is configured to drive the mobile phase at a high pressure; the fluid pump ( 20 ) is configured to drive the mobile phase at a pressure of at least 100 bar, in particular at least 500 bar, more particularly at least 1000 bar; the sample separator ( 10 ) is configured as a microfluidic device; the sample separator ( 10 ) is configured as a nanofluidic device; the sample separator ( 10 ) has an injector device ( 40 ) for introducing the fluidic sample into a fluidic path between the fluid pump ( 20 ) and the sample separation device ( 30 ) on; the sample separator ( 10 ) has a detector ( 50 ), in particular a fluorescence detector or UV absorption detector, for detecting the separated fluidic sample; the sample separator ( 10 ) has a sample fractionator ( 60 ) for fractionating the separated fluidic sample. Method for controlling a working fluid ( 102 ), the method comprising: providing working fluid ( 102 ) in a workroom ( 116 ) of a fluid valve ( 100 ), in which a first closing part ( 110 ) of the fluid valve ( 100 ) is arranged; Acting on the first closing part ( 110 ) by means of a second closing part ( 112 ) by a room separation device ( 106 ) between the working space ( 116 ) and another room ( 120 ) of the fluid valve ( 100 ), in which other room ( 120 ) the second closing part ( 112 ) is arranged such that due to the action of the fluid valve ( 100 ) opens or closes and when opening or closing the room divider ( 106 ) the working fluid ( 102 ) in the workspace ( 116 ) temporarily provides an additional volume; at least partially compensating the additional volume to thereby provide the working fluid ( 102 ) to temporarily modify the amount of work available when opening or closing. Use of a fluid valve ( 100 ) according to any one of claims 1 to 15 in supercritical liquid chromatography.

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