A springless rotary shear that produces compression forces by utilizing the stiffness properties of polymer seals. The valve is designed to produce an effective spring load, with inherent sealing force, by deflecting polymer elements whose response depends on stiffness that is governed by each component's elastic modulus and geometry. A stator seal protrudes thousandths of an inch beyond a stator seal housing. When a stator is fastened down to the stator seal housing the clamping forces are transmitted to the stator seal, rotor seal, shaft adapter, bearings and housings, and the assembly is deflected to a flush position, resulting in a sealing force between the rotor and stator seal. The transmitted sealing force is as a function of the stiffness of each component and the protrusion distance of the stator seal above the mating surface prior to fastening the stator.

FIELD OF THE INVENTION

The present invention relates to valve assemblies in general, and more particularly to spring-less multi-position valve assemblies for pressurized fluid selection and direction in the field of DNA Sequencing, in-vitro Diagnostics (IVD), HPLC (High Performance Liquid Chromatography) and Analytical instruments.

BACKGROUND OF THE INVENTION

For many years rotary shear valves have been used in pressurized fluid instruments for fluid switching, sample injection, fraction collection, stream sampling, solvent selection and fluid redirection. In the field of HPLC most conventional applications operate in the 1,000 psig to 6,000 psig high pressure domain. Only in the last few years have HPLC pressures increased up to 20,000 psig in order to reduce analysis time and increase performance. By comparison, DNA Sequencing and In-vitro diagnostic instruments in general operate at much lower pressures, from vacuum to positive pressures in the range −10 psig to 200 psig.

With regard to fluid flow control, rotary shear valves are commonly selected for a number of reasons including accuracy, precision, repeatability, reliability, chemical compatibility, ease of automation, relatively long wear and low cost. One of the primary functions of the shear valve is to create a fluidic seal, where leak rate is limited from 0.3 μL/min to 1 μL/min maximum, in order to prevent loss of sample, solvent or other pressurized fluid and achieve precision, accuracy and instrument performance. Of equal importance is the ability to direct fluid from one location to another for sample analysis, solvent selection, purging and other fluidic functions.

The means for creating a nearly leak tight seal is to apply an axial force causing a rotor element and stator element to come into contact by compression. The force created can range from 30 lbf to 800 lbf depending on the application. Most if not all rotary valves apply the compression force by means of springs, such as helical, belleville or clover. Accompanied with these components are additional parts such as washers, adjusting nuts, guides, shims and threaded features. An example of conventional loading methods is found in FIG. 3 of U.S. Pat. No. 8,622,086 where a helical spring is shown contained in an adapter component which rides on ball bearings and also positions and pushes a rotor seal against a stator seal. Another example is described in FIG. 1B of US patent application No. 2014/0191146 showing a conventional method that uses a minimum of 12 parts including 4 springs, 3 washers, spacer, thrust bearing, bearing washers and shims.

Accordingly, it is desirable to provide a low pressure micro-fluidic valve assembly that significantly reduces the part quantity by eliminating a primary element, namely the conventional spring assembly described above.

SUMMARY OF THE INVENTION

The present invention provides a spring-less micro-fluidic valve assembly that includes a stator seal device which defines a substantially planar stator face and an opposite, distal facing stator contact surface perimetrically defined by a contact surface perimeter. The stator seal device includes at least two or more stator channels extending therethrough from the stator contact surface to corresponding stator ports at the stator face. A rotor seal device22is also included having a substantially planar rotor face defining one or more rotor channels and an opposite, proximally facing rotor contact surface. The spring-less micro-fluidic valve assembly further includes a relatively rigid actuator housing having an inner wall that defines an axially extending receiving passage therethrough. The inner wall includes a distally facing housing bearing support surface. A shaft adapter is included that is configured for axial receipt in the receiving passage of the actuator housing. The shaft adapter further defines a proximally facing adapter bearing support surface and a distally facing adapter contact surface configured for contact support of the proximally facing rotor contact surface of the rotor seal device. A bearing assembly is disposed between the bearing support surface of the actuator housing and the bearing support surface of the shaft adapter for rotational support of the shaft adapter and rotor seal device thereof about a rotational axis. The spring-less micro-fluidic valve assembly further includes a relatively rigid stator seal housing defining a stator passage formed and dimensioned for axial seated receipt of the stator seal device therein. The seal housing further includes a distally facing seal housing contact surface that defines a receiving port extending into the stator passage. This receiving port is further formed and dimensioned for axial reciprocating receipt of the stator contact surface of the stator seal device therethrough. The stator seal housing includes a proximal portion configured to hard mount to a distal portion of the actuator housing, such that the actuator housing, the bearing assembly, the shaft adapter, the rotor seal device, the rotor seal device and the stator seal housing collectively cooperate to axially position the stator contact surface of the rotor seal device a substantially precise, calibrated distance, δ, beyond the housing contact surface42of the stator seal housing40, in a non-leak-tight condition.

A stator manifold device of the spring-less micro-fluidic valve assembly is configured to mount to the stator seal housing, in a compressed mount condition, such that a distally facing manifold contact surface of the manifold device initially contacts the stator contact surface, in the non-leak-tight condition, and repositions the stator contact surface, to a leak-tight condition, substantially flush with the distally facing housing contact surface of the stator seal housing. In this orientation, the rotor seal device and the rotor seal device collectively being sufficiently compressed together at a compression pressure enabling leak-tight, relatively low pressure fluid flow between corresponding stator ports and at least one rotor channel at the rotor-stator interface therebetween.

Accordingly, an apparatus and method are provided for producing compression forces by simply and efficiently utilizing the stiffness properties of polymer seals. Beginning with the removal of a conventional spring assembly, it follows that ancillary components can also be discarded. Elimination of parts decreases product cost by reducing component manufacturing expense and inventory.

In one specific embodiment, the stator seal device is comprised of a polymer material, and more particularly, a Polyetherimide (PEI).

In another configurations, the rotor seal device is selected essentially from the group consisting of a polymer, a metallic and a ceramic material. In still another, the stator seal housing and the actuator housing are comprised of a metallic material, such as a electroless nickel plated for corrosion resistance.

Yet another specific embodiment provides that the shaft adapter, the bearing assembly, and the stator manifold device are each comprised of either a metallic material or a polymer material.

Still another specific embodiment provides that the stator seal device further includes a mid section disposed between the stator face and the stator contact surface. The mid section having mid section perimeter wherein at least one portion thereof extends radially beyond that of contact surface perimeter, forming a distal facing stop surface therebetween.

In one arrangement, the calibrated distance, δ, is in the range of about 0.001″+/−0.003″ to about 0.015″+/−0.003″, and more particularly, in the range of about 0.008″+/−0.003″.

The bearing assembly is selected essentially from the group consisting of a ball bearing assembly, a polymetric spherical bearing assembly and a thrust bearing assembly.

In another specific embodiment, the distal facing stator contact surface of the stator seal device and the manifold contact surface are substantially planar and in a leak-tight relationship with one another. Similarly, the adapter contact surface of the shaft adapter and the contact surface of the rotor seal device are substantially planar and in rotationally locked together as a unit.

In still another configuration, an alignment structure cooperatively aligns and rotationally locks the rotor seal device to the shaft adapter. The alignment structure includes two or more corresponding guide pins extend distally from the adapter contact surface, and the contact surface of the rotor device define corresponding recesses for aligned receipt of the guide pins therein.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention will be described with reference to a few specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications to the present invention can be made to the preferred embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. It will be noted here that for a better understanding, like components are designated by like reference numerals throughout the various FIGURES.

Turning now toFIGS. 1-5, a spring-less micro-fluidic valve assembly, generally designated20, is provided that eliminates conventional compression spring stacks utilized to generate the compression forces necessary to form the leak-tight seal at a rotor/stator interface21of a polymer rotor seal device22and a polymer stator seal device23. The spring-less micro-fluidic valve assembly20includes the stator seal device23which defines a substantially planar stator face25and an opposite, distal facing stator contact surface26perimetrically defined by a contact surface perimeter. The stator seal device23including at least two or more stator channels extending therethrough from the stator contact surface26to corresponding stator ports at the stator face25. The spring-less micro-fluidic valve assembly20includes the rotor seal device22having a substantially planar rotor face27defining one or more rotor channels and an opposite, proximally facing rotor contact surface28, and a relatively rigid actuator housing30having an inner wall31defining an axially extending receiving passage32therethrough. The inner wall31includes a distally facing housing bearing support surface33.

FIG. 3best illustrates that a shaft adapter35is included that is configured for axial receipt in the receiving passage32of the actuator housing30. The shaft adapter35further defines a proximally facing adapter bearing support surface36and a distally facing adapter contact surface37configured for contact support of the proximally facing rotor contact surface28of the rotor seal device22. A bearing assembly38is disposed between the bearing support surface33of the actuator housing30and the bearing support surface36of the shaft adapter35for rotational support of the shaft adapter35and rotor seal device22thereof about a rotational axis. The spring-less micro-fluidic valve assembly20further includes a relatively rigid stator seal housing40defining a stator passage41formed and dimensioned for axial seated receipt of the stator seal device23therein, and a distally facing seal housing contact surface42that defines a receiving port43extending into the stator passage41. This receiving port43is further formed and dimensioned for axial reciprocating receipt of the stator contact surface26of the stator seal device23therethrough. The stator seal housing40includes a proximal portion configured to hard mount to a distal portion of the actuator housing30, such that the actuator housing, the bearing assembly38, the shaft adapter35, the rotor seal device22, the rotor seal device23and the stator seal housing40collectively cooperate to axially position the stator contact surface26of the rotor seal device23a substantially precise, calibrated distance, δ, beyond the housing contact surface42of the stator seal housing40, in a non-leak-tight condition (FIGS. 1 and 5A).

Finally, a stator manifold device45is configured to mount to the stator seal housing40, in a compressed mount condition (FIGS. 2 and 5B), such that a distally facing manifold contact surface46of the manifold device45initially contacts the stator contact surface26, in the non-leak-tight condition, and repositions the stator contact surface26, to a leak-tight condition (FIG. 5B), substantially flush with the distally facing housing contact surface42of the stator seal housing40. In this orientation, the rotor seal device23and the rotor seal device22collectively being sufficiently compressed together at a compression pressure enabling leak-tight, relatively low pressure fluid flow between corresponding stator ports and at least one rotor channel at the rotor-stator interface21therebetween.

Accordingly, a sufficient degree of compression forces are generated between the stator seal and the rotor seal by simply and efficiently utilizing the stiffness properties of polymer seals. For low fluid pressure situations, this axial compressive pressure enables the removal of conventional spring stack that are widely applied, as well as an ancillary components that are used therewith. Such an elimination of parts decreases product cost by reducing component manufacturing expense and inventory. In addition, fewer parts typically lead to an increase in product reliability and performance. Finally, given the direction technology is driven in terms of smaller and more compact designs, it will be understood how the present invention enables significant reduction of the overall valve size which contributes to a likewise beneficial reduction in instrument size and cost.

The present invention is particularly suitable for lower pressure applications, such as DNA Sequencing and In Vitro Diagnostics, and operating at fluid pressures operating in the range of about −10 psi to about 200 psi. For these applications, the generated compression forces at the rotor/stator interface21should be in the range of about 500 psi to about 1500 psi.

The operation of the present invention depends on the stiffness characteristics of the components under compression. Stiffness, K, is defined as the rigidity of an object and resistance to deformation. All materials, whether metals, plastics or elastomers have a property called stiffness. In general, K is a constant dependent upon geometric factors of the object such as Cross-sectional Area, A, Thickness, t, and the Elastic Modulus, E. The formula for stiffness is:
K=E*A/t.[1]

In addition stiffness can be defined as:
K=F/δ[2]

where F is the force applied to the component and δ is the displacement produced by the force. Force F is of particular importance to the present invention and can be easily derived from equation [2] giving:
F=K*δ.[3]

Therefore, effective spring load, with inherent sealing force, is produced by deflection of polymer elements and depends on stiffness that is governed by each component's elastic modulus and geometry. In addition, since stiffness may not be linear for some materials, the amount of deflection will affect its value and consequently affect the effective spring load.

These equations are of course a simplification of more complex mathematical models that predict how an object will deform, especially in the case of polymers where strain under load, which is not linear, will occur in more than one direction and depend on how the object is constrained. However, if strain is limited to the elastic range of the material and forces are applied in only one direction, it has been observed that linear formula combined with empirical data are sufficient and effective for estimating how an object or assembly of components deflects under an axially applied load, or for estimating the resultant load given a defined deformation. Since deflection of the component must be relatively small, so as to prevent plastic deformation which causes unpredictable change in shape over time, it is therefore necessary to design components with critical features having tolerances in the range of about +/−0.001″.

In accordance with the present invention, as shown inFIGS. 1 and 2, a full valve assembly20is provided with a size seventeen (17) motor62. As mentioned above, the valve assembly20includes two primary components, a polymer rotor seal device22and polymer stator seal device23. These seals are selected of a material with known physical properties, which are designed to be accurately compressed (deflected) a designed amount. Hence, upon assembly of the valve assembly20, the requisite axial compression force between the rotor seal device22and the stator seal device23is generated, forming a fluid-tight seal at the rotor/stator interface21.

Briefly, referring back toFIGS. 1-4, the rotor seal device22is supported by a shaft adapter28which sits atop the bearing assembly38. In this specific embodiment, the bearing assembly38is provided by ball bearings that are supported between the bearing support surface33(e.g., a bearing race) of the actuator housing30and the bearing support surface36of the shaft adapter28. When the stator manifold device45is mounted to the stator seal housing40, the manifold contact surface46of the manifold device contact the stator contact face26of the stator seal device23, compressing the stator seal device against the rotor seal device22(i.e., the compressed mount condition ofFIGS. 2 and 5B).

In one specific example of the present invention, the shaft adapter28is comprised of unfilled nylon, the rotor seal device22is comprised of PolyChloro-TriFluoro-Ethylene (PCTFE), the stator face25is composed of Ultra H-high Molecular Weight PolyEthylene (UHMWPE) while the stator manifold device45material is ULTEM® Polyetherimide. The stator manifold device45can be a stand-alone component with ports for direct application of input and output lines or it can be a manifold to which are assembled a variety of parts including pump and liquid sensor with a variety of port and channel configurations and capable of mounting to an analytical instrument.

FIG. 5Abest illustrates a closer view of the stator seal device23where the corresponding substantially planar contact surface26is protruding above the mating surface of the stator seal housing40. This particular embodiment has contact surface26protruding (i.e., the calibrated distance, δ) about 0.008″+/−0.003″. beyond the seal housing contact surface42of the stator seal housing40, although the range of protrusion without significant plastic deformation is a range of about 0.001″+/−0.003″ to about 0.015″+/−0.003″. When the stator manifold device45is fastened down to the stator seal housing40(as shown inFIG. 2), the clamping forces are transmitted to the stator seal device23, rotor seal device22, shaft adapter28, bearings38and housings30and40. Consequently, the assembly is deflected 0.008″ to a flush position (i.e., the substantially planar contact surface26being deflected flush with the substantially planar seal housing contact surface42, as shown inFIG. 5B), resulting in a sealing force between the rotor seal device22and stator seal23at the rotor/seal interface21(FIG. 2). The transmitted sealing force is a function of the stiffness of each component and the initial distance above flush (protrusion of the stator seal above the mating surface prior to fastening the stator).

With the aid of a compression test instrument, such as the INSTRON® Compression Tester, the stiffness of components and sub-assemblies can be determined for the purpose of initial estimation and to derive final valve load-deflection relationships. In one particular example, the average stiffness of the sub-assembly comprised of the actuator housing30, ball bearings38, and shaft adapter in the present invention was measured to be K=96.7 k lb/in. Separately, the average stiffness of the PCTFE rotor seal device22and UHMWPE stator seal device23were measured to be about 148 k lb/in and about 37 k lb/in, respectively. Therefore, the equation for the valve assembly stiffness is 1/K=1/96.7 k+1/148 k+1/37 k equating to a total sub-assembly stiffness of K=22.7 k lb/in.

Using the INSTRON® tester for analyzing the assembled valve results in a measurement of about 22.9 k lb/in in the range about 0.005″ to 0.011″, which confirms the accuracy of individual measurements. Based on an assembly stiffness of about 22.9 k lb/in, the resulting sealing force can range from about 114 lbf to about 252 lbf for a deflection of about 0.008+/−0.003 inches. It is interesting to note that the calculated valve stiffness is 32 k lb/in, obtained using the equation[1] K=E*A/t, giving a 40% error above the measured stiffness. Although general material property data and simplification of geometric parameters are sufficient for initial estimation, the most effective design will rely on empirical data both for accuracy and for a better understanding of the load-deflection relationship to prevent operating in the plastic deformation region.

In one example of the present invention, typical materials used for the polymer seals in low pressure applications will have a tensile strength ranging from about 3,000 psi to about 10,000 psi, and an elastic modulus ranging from about 100,000 psi to about 200,000 psi. For high pressure applications, in another example, the polymer tensile strength can reach up to about 25,000 psi with elastic modulus up to about 1×106psi.

It has been observed that an important parameter for a repeatable and robust design is to control tolerances. If the tolerances are too wide, then on the lower end of the tolerance band, there will be no material to deflect. On the upper end of the tolerance band, when the tolerances are too wide, too much strain can result in poor performance. Excessive deflection of polymer materials, for instance, can cause plastic deformation, resulting in a loss of sealing force, and even stress failure.

In the present invention, the calibrated distance, δ, the stator seal contact surface26sits above the housing contact surface42prior to fastening the stator is calculated to be about 0.008″ with an RSS (root sum square) tolerance of +/−0.003″. Polymer seal thickness tolerances are tightly controlled through proprietary lapping and polishing processes, resulting in tolerances in the range of about +/−0.001 inches. Other critical dimension tolerances in the actuator housing30and stator seal housing40are easily controlled by standard machining practices. Manufacturing cost, moreover, is kept at a minimum by die casting metal parts, secondary machining operations and injection molding plastics.

FIG. 6represents topside the die cast actuator housing30which includes multiple arc segments47with an outside diameter wall tightly toleranced to align with a receiving wall44of the stator seal housing40. In addition, clocking or angular alignment and positioning of the stator seal housing40is accomplished using three slots48between the arc segments47of the housing30. The actuator housing30features a ball bearing race (housing bearing support surface)33for a quantity of fourteen (in this example) steel ball bearings of the bearing assembly38. The actuator housing is preferably electroless nickel plated for corrosion resistance and to provide a hard, durable wear surface for the steel ball bearings.

The back side of the actuator housing30, as shown inFIG. 7, and an inner wall49having a diameter configured for receipt of a pressed-in injection molded ring gear51. The housing further includes four housing slots50which are sized for axial sliding receipt four alignment ring gear ribs52of the actuator housing30, as shown inFIG. 8.

Turning now toFIG. 9, the stator seal housing40front side is shown which includes cast-in alignment pins55protruding distally from the housing contact surface42of the stator seal housing40. These pins55enable positioning, alignment and mounting support for the contact surface46of the stator manifold device45. For the easy for fabrication, both the housing contact surface42and the manifold contact surface46are substantially planar, as is the stator contact surface.

The stator seal housing40back side (FIG. 10) includes the tightly tolerance inside wall44, and three alignment ribs56protruding radially inward therefrom for engaging the arc segments47of the actuator housing30. In addition, an interior wall54, that defines a portion of the stator passage41, further includes three positioning ribs57formed and dimensioned to position and align the stator contact surface26through the receiving port43of the stator seal housing40. The entire die cast part is electroless nickel plated for corrosion resistance.

Finally, the interior walls defining the receiving port43of the stator seal housing40are relatively tightly tolerance d for reciprocating receipt to the contact surface perimeter of the nipple portion59of the stator seal device23. However, the interior wall of the receiving port43, and the outer wall of the contact surface perimeter must be sized to enable axial movement of the nipple portion59during compression of the stator device23. Hence, some diametric expansion during the compression must be take into account.

FIG. 11depicts the stator face25of stator seal device23. Alignment slots61are provided for the corresponding positioning ribs57when seated in the stator passage of the stator seal housing40. The midsection of the stator seal device23is diametrically wider than that of the outer wall of the nipple portion59, at least at portions, forming a circular shoulder with a distal facing stop surface63. This shoulder enables the accommodation of the slots61, as well as limiting the distal travel of the nipple portion through the receiving port43.

In one alternative embodiment of the present invention, as shown inFIGS. 12-15, the valve assembly20similarly consists of a polymer rotor seal device22and polymer stator seal device23. The rotor seal device22is rotatably supported by a shaft adapter28which sits atop the bearing assembly38. In this alternative configuration, the bearing assembly is provided by a two-part spherical thrust bearing38contained in receiving passage32of the actuator housing30. Both the inner wall31and housing bearing support surface33provide rotational support to the shaft adapter28, and thus, and the rotor seal device22. Briefly, s shown inFIGS. 14 and 15, the two-part spherical thrust bearing38includes a base portion67and a spherical washer70.

Similarly, a stator manifold device45is mounted to the stator seal housing40and contacts the contact surface26of the stator seal device23, compressing the sub-assembly together, in the same manner as previously described inFIGS. 5A to 5B.

In this specific alternative embodiment ofFIGS. 12-15, the shaft adapter28is made from aluminum or steel, the rotor seal device22material is PCTFE, the stator face seal23is UHMWPE while the stator manifold device45material is ULTEM®. The stator manifold device45can be a stand-alone component with ports for direct application of input and output lines or it can be a manifold to which are assembled a variety of parts including pump and liquid sensor with a variety of port and channel configurations and capable of mounting to an analytical instrument.FIGS. 5A and 5B, applies to this design variation just as the initial embodiment where the contact surface26of the stator seal device23protrudes thousandths of an inch beyond the seal housing contact surface42of the stator seal housing40.

FIG. 13best illustrates the full valve assembly20with a dc motor71and gear train (stator manifold removed). In this embodiment, as shown inFIG. 18, the stator seal housing40includes a mechanical stop80to enable a two-position valve configuration. However, the dc motor71may come equipped with any one of many rotary position sensor devices to command, sense and control multiple angular positions. The dc motor may also be assembled to a single gear train or multiple stacks of gear boxes.

Referring now toFIG. 16, a die cast actuator housing30is provided for the valve assembly20alternative embodiment ofFIGS. 12-15. In this specific configuration, the inner wall31and the bearing support surface33are sized to provide support for the bearing assembly38. In this configuration, the bearing assembly38is provided by a spherical thrust bearing, and thus, support surface33provides axial support for the base67of the thrust bearing.

Again, similarly, the inner wall31has a diameter tightly toleranced to align, and cooperatively receive portions of the stator seal housing40therein. In addition, clocking or angular alignment and positioning of the stator seal housing40with the actuator housing30is similarly accomplished using three slots48formed in the mating surface facing the seal housing.

The entire actuator housing30is electroless nickel plated for corrosion resistance or the part can be made of steel. Also included are thru holes75for mounting the actuator housing30to the stator seal housing40, thru holes76for mounting the dc motor and threaded holes77for fastening the stator manifold device45. Furthermore, a mechanical slot78is provided that is used for engaging a mechanical stop80on the stator seal housing40(FIG. 18).

Referring now toFIG. 17, a front side of the stator seal housing40is shown of the alternative embodiment valve assembly ofFIGS. 12-15, illustrating cast-in alignment pins81for positioning and alignment of the stator manifold device45on the front side.FIG. 18illustrates a backside of the stator seal housing40which includes the three alignment ribs56protruding outward from an alignment ring79. The ribs56and outer diameter of the alignment ring79are tightly tolerance with the corresponding receiving slots48and the inner wall31of the actuator housing30(FIGS. 14 and 16). In addition, referring back toFIG. 18, the stator seal housing40includes three interior positioning ribs57for receipt in corresponding slots61in the stator seal device23for alignment thereof and an inside diameter for receipt and alignment of the stator seal outside diameter.

If it is necessary to mount the valve from the back side to a manifold, two thru holes82are supplied on wing features. Threaded holes85are also available for mounting the actuator housing30to the stator seal housing40. Furthermore, as shown inFIGS. 18 and 19, a mechanical hard stop80is provided that limits rotation of the shaft adapter28, rotatably supporting the rotor seal device22, in order to provide position fluid control. The entire die cast part is electroless nickel plated for corrosion resistance or can be made from steel.

Another specific configuration of the thrust bearing embodiment is shown inFIGS. 20-22. In this thrust bearing configuration of the bearing assembly38, the valve assembly20includes a ceramic rotor seal device22, a ceramic stator face seal86and polymer stator seal device23. The ceramic rotor seal device22is supported by a shaft adapter28which sits atop a two part spherical thrust bearing38contained in the receiving passage32of actuator housing30. A stator manifold device45is mounted to the stator seal housing40and contacts the stator contact surface26of the stator seal device23.

In this variation of the invention the ceramic rotor seal device84and ceramic stator face seal86are sandwiched between a polymer spherical thrust bearing38and the polymer (PCTFE or similar material) stator seal device23. The polymer combination functions to produce a spring effect while at the same time enables the hard ceramic surfaces of the rotor seal device84and the stator face seal86to be oriented substantially parallel to one another even though other components in the stack may have non-parallel surfaces in contact. A condition of non-parallelism between hard surfaces contributes to reduced life caused by uneven loading and wear of the surfaces. However, for this alternate design, the polymer spherical thrust bearing38and the polymer stator seal device23allow the hard coated ceramic rotor seal to rotate on the ceramic stator face seal in a more uniform motion as the bearing on one end and polymer seal on the other take up axial and planar misalignments. Again,FIGS. 5A and 5Bapplies to this design variation just as the initial embodiment where the stator face protrudes thousandths of an inch beyond the stator housing.

Another variation of the present invention, shown inFIGS. 23-25, consists of addition of a polymer energizer87and ceramic rotor seal device86. The rotor seal device is supported by a shaft adapter28which sits over the polymer energizer87. A two part polymer spherical thrust bearing (i.e., bearing assembly38) is inserted into the receiving passage32, defined by the bearing support surface33and inner wall31, of the actuator housing30to provide bearing support as well as contribute as a spring element. A stator manifold device45is mounted directly to the actuator housing30, in this embodiment, eliminating the stator seal device and the stator seal housing of the previous embodiments. In this configuration, the substantially planar manifold contact surface46provides the stator face88that directly contacts the rotor face90of the coated ceramic rotor seal86.

In this variation of the present invention, the flat washer-shaped polymer energizer87is comprised from PCTFE or other polymer material with stiffness in the range about 50 k lb/in to about 200 k lb/in. The polymer combination of polymer energizer87and polymer thrust bearing38cooperates to produce a spring effect while at the same time enables the face of the hard ceramic rotor86to be oriented substantially parallel with the metal surface or face of the stator manifold device45even though other components in the stack may have non-parallel surfaces in contact. A condition of non-parallelism between hard surfaces contributes to reduced life caused by uneven loading and wear of the surfaces. However, for this alternate design the polymer spherical bearing and polymer energizer allow the hard coated ceramic rotor seal to rotate on the coated metallic stator in a more uniform motion as the bearing and polymer energizer take up axial and planar misalignments. The concept ofFIGS. 5A and 5B, applies to this design variation except in this configuration, it is the rotor face90of the rotor seal device86that protrudes the calibrated distance, δ, beyond the substantially planar distal contacting surface91of the actuator housing30.

Although the present invention has been primarily described as applying to shear face valve assemblies for applications below 2000 psi, and for pressure applications that require high lifecycle capabilities (e.g., such as all HPLC Instrument platforms/designs), it will be appreciated that this technology may be applied to all shear valve assembly platforms/designs (such as AI (analytical chemistry) and IVD (In-vitro Diagnostics)).