Patent ID: 12234919

DETAILED DESCRIPTION OF AN EMBODIMENT OF THE DISCLOSURE

The following description of technology is merely exemplary in nature of the subject matter, manufacture and use of one or more inventions, and is not intended to limit the scope, application, or uses of any specific invention claimed in this application or in such other applications as may be filed claiming priority to this application, or patents issuing therefrom. Regarding methods disclosed, the order of the steps presented is exemplary in nature, and thus, the order of the steps can be different in various embodiments. “A” and “an” as used herein indicate “at least one” of the item is present; a plurality of such items may be present, when possible. Except where otherwise expressly indicated, all numerical quantities in this description are to be understood as modified by the word “about” and all geometric and spatial descriptors are to be understood as modified by the word “substantially” in describing the broadest scope of the technology. “About” when applied to numerical values indicates that the calculation or the measurement allows some slight imprecision in the value (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If, for some reason, the imprecision provided by “about” and/or “substantially” is not otherwise understood in the art with this ordinary meaning, then “about” and/or “substantially” as used herein indicates at least variations that may arise from ordinary methods of measuring or using such parameters.

All documents, including patents, patent applications, and scientific literature cited in this detailed description are incorporated herein by reference, unless otherwise expressly indicated. Where any conflict or ambiguity may exist between a document incorporated by reference and this detailed description, the present detailed description controls.

Although the open-ended term “comprising,” as a synonym of non-restrictive terms such as including, containing, or having, is used herein to describe and claim embodiments of the present technology, embodiments may alternatively be described using more limiting terms such as “consisting of” or “consisting essentially of.” Thus, for any given embodiment reciting materials, components, or process steps, the present technology also specifically includes embodiments consisting of, or consisting essentially of, such materials, components, or process steps excluding additional materials, components or processes (for consisting of) and excluding additional materials, components or processes affecting the significant properties of the embodiment (for consisting essentially of), even though such additional materials, components or processes are not explicitly recited in this application. For example, recitation of a composition or process reciting elements A, B and C specifically envisions embodiments consisting of, and consisting essentially of, A, B and C, excluding an element D that may be recited in the art, even though element D is not explicitly described as being excluded herein.

As referred to herein, all compositional percentages are by weight of the total composition, unless otherwise specified. Disclosures of ranges are, unless specified otherwise, inclusive of endpoints and include all distinct values and further divided ranges within the entire range. Thus, for example, a range of “from A to B” or “from about A to about B” is inclusive of A and of B. Disclosure of values and ranges of values for specific parameters (such as amounts, weight percentages, etc.) are not exclusive of other values and ranges of values useful herein. It is envisioned that two or more specific exemplified values for a given parameter may define endpoints for a range of values that may be claimed for the parameter. For example, if Parameter X is exemplified herein to have value A and also exemplified to have value Z, it is envisioned that Parameter X may have a range of values from about A to about Z. Similarly, it is envisioned that disclosure of two or more ranges of values for a parameter (whether such ranges are nested, overlapping or distinct) subsume all possible combination of ranges for the value that might be claimed using endpoints of the disclosed ranges. For example, if Parameter X is exemplified herein to have values in the range of 1-10, or 2-9, or 3-8, it is also envisioned that Parameter X may have other ranges of values including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, 3-9, and so on.

When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

FIG.1illustrates a rotary valve10in accordance with an embodiment of the present disclosure. The rotary valve10may be in fluid communication with at least one fluid source (not depicted) for supplying at least one fluid (not depicted) and at least one fluid destination (not depicted) for receiving at least one fluid (not depicted). In certain embodiments, the rotary valve10may comprise a valve housing60and a flow control assembly14disposed therein. The flow control assembly14comprises a fixed disc20, a rotary disc40, a biasing seal55, and a drive shaft80having a flow chamber95integrated therein. The drive shaft80drives the motion of a rotatable assembly15of the flow control assembly14comprising the rotary disc40, the biasing seal55, and drive shaft80(including the integrated flow chamber95formed therein), which all rotate in unison relative to the fixed disc20of the flow control assembly14. The fixed disc20is affixed in position both rotationally and axially within the valve housing60, hence the rotatable assembly15rotates relative to each of the valve housing60and the fixed disc20received therein. The rotation of the rotatable assembly15relative to the fixed disc20and the valve housing60facilitates a switching of a mode of operation of the rotary valve10between the different operational modes thereof, as elaborated on hereinafter in greater detail.

As shown, the valve housing60may include a pair of fluid inlets16a,16band a pair of fluid outlets18a,18b. Each of the fluid inlets16a,16bmay be in fluid communication with the at least one fluid source and each of the fluid outlets18a,18bmay be in fluid communication with the at least one fluid destination. It is understood that the valve housing60may include more or less inlets16a,16b, and more or less outlets18a,18bthan shown, as desired, while remaining within the scope of the present invention. It is further understood that each of the fluid inlets16a,16bmay be in fluid communication with the same fluid source or separate and distinct fluid sources and each of the fluid outlets18a,18bmay be in fluid communication with the same fluid destination or separate and distinct fluid destinations.

The rotary valve10as shown and described herein may also be utilized for any number of different applications and for selectively conveying any variety of different fluids therethrough. As one example, the rotary valve10may be a bypass, diverter, or switching valve as utilized in controlling a flow of a liquid coolant of an automotive-based coolant fluid system from two upstream-arranged flow paths to two downstream-arranged flow paths. However, it should be readily apparent that the presently disclosed rotary valve10may be utilized in substantially any automotive or vehicular application corresponding to the described flow configurations through the rotary valve10, including the control of various fluids associated with operation of a hydraulic system, a pneumatic system, a fuel system, or a heating, ventilating, and air conditioning (HVAC) system of the associated vehicle, or the like. In addition to a liquid coolant, the fluids suitable for use with the rotary valve10may be air, any hydraulic fluids, any types of fuel, or any refrigerants typically utilized with respect to such vehicular systems, as desired. However, it should also be apparent that the present rotary valve10may be adapted for use with any fluid associated with any fluid conveying system without necessarily departing from the scope of the present invention, and is therefore not limited to automotive or vehicular applications.

In an exemplary embodiment, the valve housing60may include a first inlet16afor receiving a first fluid from a first fluid source, a second inlet16bfor receiving a second fluid from a second fluid source, a first outlet18afor distributing one of the first fluid or the second fluid to a first fluid destination, and a second outlet18bfor distributing one of the first fluid or the second fluid to a second fluid destination. However, it should be readily apparent to one skilled in the art that the flow configurations disclosed as occurring from each of the inlets16a,16bto each of the outlets18a,18bmay alternatively include a flow in the opposing direction from one of the identified outlets18a,18bto one of the identified inlet16a,16bwhile remaining consistent with the present disclosure. As another example, the rotary valve10may include a switching capability wherein one of the identified inlets16a,16bis switched to act as an outlet for certain modes of operation, and/or where one of the outlets18a,18bis switched to act as an inlet for certain modes of operation, as desired, while remaining within the scope of the present invention.

As shown inFIGS.1,2, and6-9, the valve housing60may include an opening67defined by a substantially cylindrical circumferential wall69, a cover63removably coupled to the valve housing60at a first axial end61of the circumferential wall69, and an axial end wall68formed at a second axial end62of the circumferential wall69disposed opposite the cover63. However, it should be appreciated that the opening67may have any size and shape, as desired, to provide a desired flow of the one or more fluids therethrough while accommodating the flow control assembly14therein.

The cover63includes an opening64formed therethrough along the central axis of the valve housing60that is configured to receive an actuator engagement stem91of the drive shaft80therethrough. The cover63may be removably coupled to a rim of the valve housing60with an intervening sealing element (not shown) compressed therebetween, such as by utilizing threaded fasteners for urging the cover63towards the rim of the valve housing60. Any configuration of the cover63relative to the valve housing60that provides a fluid-tight seal may be utilized without departing from the scope of the present invention.

One or more O-rings or other gaskets66may be received between an inner circumferential surface of the cover63defining the opening64(shown and identified inFIG.6) thereof and an outer circumferential surface of the drive shaft80to form a fluid-tight seal therebetween, including during periods of rotation of the drive shaft80relative to the valve housing60. A chamber having the gaskets66disposed therein may be partially defined by an annular shoulder of the cover63formed along the opening64thereof at a first axial end of the chamber and an annular shoulder65of the drive shaft80at a second axial end of the chamber. However, alternative sealing arrangements may be present between the drive shaft80and the valve housing60while remaining within the scope of the present invention, hence the described configuration is not limiting to the present invention.

The opening67may be in fluid communication with each of the inlets16a,16band each of the outlets18a,18b. In certain embodiments, the first inlet16ais in fluid communication with the opening67through an aperture67aformed in the circumferential wall69, and the second inlet16band each of the outlets18a,18bare in fluid communication with the opening67through respective apertures67b,67c,67dformed in the axial end wall68. As such, the flow of the first fluid into the opening67via the first inlet16amay be substantially perpendicular to the flow of the second fluid into the opening67via the second inlet16band the flow of the first and second fluids out of the opening67via each of the outlets18a,18b. That is, the flow of the first fluid into the opening67through the aperture67amay be transverse to the axial direction of the valve housing60, which extends between the cover63and the axial end wall68thereof. This configuration may include the flow of the first fluid being perpendicular to the axial direction and/or extending radially through a central axis of the valve housing60when passing across the aperture67a, wherein the aperture67acorresponds to a boundary fluidly coupling an interior of the first inlet16ato the opening67. In contrast, the flow through each of the inlet16band the outlets18a,18bmay be substantially parallel to the axial direction of the valve housing60when passing through each of the respective apertures67b,67c,67dformed through the axial end wall68and leading towards one of the inlet16bor the outlets18a,18b. Specifically, an aperture67bcorresponds to a boundary fluidly coupling the second inlet16bto the opening67, an aperture67ccorresponds to a boundary fluidly coupling the first outlet18ato the opening67, and an aperture67dcorresponds to a boundary fluidly coupling the second outlet18bto the opening67.

As shown inFIG.1, the aperture67ais formed along an inner circumferential surface70of the circumferential wall69and may be substantially circular or elliptical in shape. As best shown inFIGS.2and3, the aperture67bcorresponding to the second inlet16bis formed along an inner surface72of the axial end wall68at a first position disposed between the axis of rotation of the drive shaft80(corresponding to the central axis of the valve housing60) and a first circumferentially extending segment of the inner circumferential surface70of the circumferential wall69, the aperture67ccorresponding to the first outlet18ais formed along the inner surface72of the axial end wall68at a second position disposed between the axis of rotation of the drive shaft80and a second circumferentially extending segment of the inner circumferential surface70, and the aperture67dcorresponding to second outlet18bis formed along the inner surface72of the axial end wall68at a third position disposed between the axis of rotation of the drive shaft80and a third circumferentially extending segment of the inner circumferential surface70. The aperture67ccorresponding to the first outlet18amay be disposed at a position along the inner circumferential surface70that is diametrically opposed to the position of the aperture67aformed therethrough and corresponding to the first inlet16a. In the present embodiment, each of the apertures67b,67c,67dincludes a perimeter shape resembling a sector of a circle, and each of the apertures67b,67c,67doccupies about a third of the circular cross-sectional shape of the axial end wall68at the inner surface72thereof.

However, alternative configurations of the apertures67b,67c,67dmay be utilized through the axial end wall68for selectively communicating the fluid to a desired one or combination of the inlet/outlets16b,18a,18b, so long as the apertures67b,67c,67dare positioned for receiving a desired distribution of the fluid passing through the rotary valve10based on the instantaneous rotational position of the rotatable assembly15relative to the fixed disc20, as explained hereinafter. The valve housing60may accordingly include an inner surface, as defined by the inner circumferential surface70of the circumferential wall69and the inner surface72of the axial end wall68, that defines each of the opening67, the aperture67a, the aperture67b, the aperture67c, and the aperture67d, wherein each of the apertures67a,67b,67c,67dforms a boundary into or out of the opening67.

The second inlet16band each of the outlets18a,18bmay include a ninety-degree bend formed therein at positions spaced axially from the respective apertures67b,67c,67dthereof, as more clearly depicted inFIGS.6-9. However, the inlet16band the outlets18a,18bmay alternatively be provided in the absence of such ninety-degree bends, and may instead extend away from the valve housing60at any angle or configuration, including exclusively axially, so long as each of the inlet16band the outlets18a,18bis in fluid communication with the opening67via a corresponding one of the apertures67b,67c,67dformed through the axial end wall68.

As best shown inFIG.2, the axial end wall68of the valve housing60further includes at least one locating structure78extending axially from the inner surface72thereof for establishing the fixed position of the fixed disc20relative to the valve housing60, and more specifically for providing a structural feature that is not axially symmetric relative to the axis of rotation of the drive shaft80such that the fixed disc20cannot undesirably rotate relative to the valve housing60about a central axis of the fixed disc20substantially aligned axially with the axis of rotation of the drive shaft80. Each of the locating structures78also extends radially inwardly from the otherwise cylindrical shape of the inner circumferential surface70at a position where the inner circumferential surface70meets the axial end wall68.

The fixed disc20is substantially cylindrical in shape and includes a first face23, an opposing second face24, and an outer circumferential surface25connecting the first face23to the second face24with respect to the axial direction of the drive shaft80. The outer circumferential surface25includes a shape and size corresponding to a cylindrically shaped portion of the inner circumferential surface70of the circumferential wall69, and at least one locating segment27with each of the locating segments27having a shape and size corresponding to one of the locating structures78of the valve housing60. Each of the locating segments27is provided as a radially inwardly extending indentation formed in the circumferential surface25having the same configuration as a shoulder of each of the corresponding locating structures78.

The first face23, which may alternatively be referred to as the first axial end surface23of the fixed disc20, is arranged to face outwardly towards the first end61of the valve housing60, whereas the second face24, which may alternatively be referred to as the second axial end surface24of the fixed disc20, is arranged to face outwardly towards the second end62of the valve housing60. The first face23and the second face24are arranged parallel to each other, and each face23,24is planar in configuration. The plane of each face23,24is arranged to be substantially perpendicular to the axis of rotation of the drive shaft80. The first face23is configured to face towards and engage a face of the rotary disc40while the second face24may be configured to face towards and sealingly engage a sealant, gasket, or other sealing means disposed on the inner surface72of the axial end wall68around a perimeter of each of the apertures67b,67c,67d. The outer circumferential surface25of the fixed disc20is fitted to the inner circumferential surface70of the valve housing60with the cylindrical surfaces thereof axially aligned with corresponding cylindrical portions of the inner circumferential surface70and each of the locating segments27axially aligned with a corresponding one of the locating structures78.

The fixed disc20further includes a first flow opening31, a second flow opening32, and a third flow opening33formed therethrough from the first face23to the second face24thereof. Each of the flow openings31,32,33accordingly provides fluid communication between the first face23and the second face24of the fixed disc20. The first flow opening31is axially aligned with the aperture67b, the second flow opening32is axially aligned with the aperture67c, and the third flow opening33is axially aligned with the aperture67d.

The first flow opening31includes a peripheral shape that substantially corresponds to and is axially aligned with that of the aperture67b, the second flow opening32includes a peripheral shape that substantially corresponds to and is axially aligned with that of the aperture67c, and the third flow opening33includes a peripheral shape that substantially corresponds to and is axially aligned with that of the aperture67d. In the present embodiment, each of the flow openings31,32,33includes a perimeter shape resembling a truncated sector of a circle, wherein a radial inner portion of the perimeter is truncated in an arcuate shape having a constant radius of curvature relative to the axis of rotation of the drive shaft80. In the present embodiment, each of the flow openings31,32,33occupies about a third of the circular cross-sectional shape of the fixed disc20while extending angularly through an angle of about 120° relative to the axis of rotation of the drive shaft80, but alternative configurations of the flow openings31,32,33may be utilized through the fixed disc20for selectively communicating the first and second fluids therethrough while remaining within the scope of the present invention.

The fixed disc20includes a shaft receiving indentation34formed in the first face23thereof and extending towards the second face24thereof. The shaft receiving indentation34is cylindrical in shape and includes a depth with respect to the axial direction of the drive shaft80sufficient to provide an axial clearance between a base surface of the shaft receiving indentation34and a distal end of the drive shaft80. The cylindrical shape of the shaft receiving indentation34may be centered relative to the axis of rotation of the drive shaft80.

The rotary disc40is substantially cylindrical in shape and includes a first face41, an opposing second face42, and an outer circumferential surface44connecting the opposing faces41,42with respect to the axial direction of the drive shaft80. As best shown inFIG.1, the outer circumferential surface44is divided into a cylindrical segment45having a shape and size corresponding to a cylindrically shaped portion of the inner circumferential surface70of the circumferential wall69and a flow passage segment46having a shape and size substantially corresponding to any one of the flow openings31,32,33formed through the fixed disc20. Specifically, the flow passage segment46is provided as a radially inwardly indented portion of the outer circumferential surface44forming an outer flow passage47of the rotary disc40providing fluid communication between the opposing faces41,42thereof along a periphery of the rotary disc40.

The outer flow passage47of the presently disclosed embodiment is defined by an open space formed between the inner circumferential surface70of the valve housing60and the flow passage segment46of the outer circumferential surface44, which results in the outer flow passage47having the shape of a radially inwardly truncated sector of a circle in similar fashion to each of the flow openings31,32,33. The outer flow passage47may extend angularly around the axial direction of the drive shaft80about 120° to correspond to about a third of a cross-section of the opening67at the axial position of the rotary disc40. However, it should be readily apparent that substantially any shape and configuration of the outer flow passage47may be provided around the rotary disc40so long as the resulting outer flow passage47is able to be selectively placed in fluid communication with a desired one of the flow openings31,32,33formed through the fixed disc20. For example, instead of including a radially inwardly extending indentation for forming the open space defining the outer flow passage47, the outer flow passage47may instead be provided as a through-hole or opening passing from the first face41to the opposing second face42of the rotary disc40, including having the same general shape and configuration of either of the disclosed flow openings31,32,33of the fixed disc20.

A shaft receiving opening48is formed through the rotary disc40at a position axially aligned with the drive shaft80to allow for passage of the drive shaft80through the rotary disc40from the first face41to the opposing second face42thereof. The shaft receiving opening48may include substantially any axially non-symmetric shape for transferring rotational motion from a disc engagement stem92of the drive shaft80to the rotary disc40via engagement between an outer circumferential surface of the disc engagement stem92and an inner circumferential surface of the rotary disc40defining the shaft receiving opening48.

The rotary disc40further includes an inner flow passage49formed therethrough from the first face41to the second face42thereof, thereby allowing the inner flow passage49to provide fluid communication between the opposing faces41,42of the rotary disc40along an interior thereof. The inner flow passage49extends angularly about 240° around a central portion of the rotary disc having the shaft receiving opening48disposed therein to correspond to the inner flow passage49being axially aligned with any two of the flow openings31,32,33formed through the fixed disc20, and hence any two of the apertures67b,67c,67dformed along the inner surface72of the axial end wall68. The inner flow passage49accordingly occupies about two-thirds of a cross-section of the opening67at the axial position of the rotary valve40.

The fixed disc20and the rotary disc40may each be formed from a ceramic material having a relatively low co-efficient of friction and a correspondingly high resistance to wear when the discs20,40are caused to move relative to each other when the opposing faces23,42thereof are placed in contact with each other. The ceramic material may also include a relatively low coefficient of thermal expansion to prevent excessive deformation of either of the discs20,40when exposed to varying temperatures, such as when the fluid passing through the rotary valve10varies in temperature. The ceramic material may also be selected such that the engaging faces23,42can be precision-machined to be planar in configuration such that the facing engagement of the faces23,42prevents the flow of a fluid therebetween. A fluid-tight seal may accordingly be formed directly between the engaging faces23,42of the discs20,40absent the intervention of any form of additional sealing element, O-ring, gasket, or the like, due to the planar face-to-face engagement present between the faces23,42.

The discs20,40may alternatively be formed from a first material that is coated at certain surfaces with a second material. The second material may be disposed at those surfaces configured to make sliding engagement with another surface, such as along the engaging faces23,42, or along the outer circumferential44surface of the rotary disc40. The second material may be the ceramic material as described above. The second material may alternatively be a diamond material or a diamond-like carbon (DLC) material. The second material may alternatively be a lubricant, such as a water-insoluble lubricant. The faces23,42and/or the outer circumferential surface44of the rotary disc40may include any combination of any of the materials and coatings as described herein while remaining within the scope of the present invention, so long as the facing engagement present between the outwardly exposed faces23,42is utilized to provide a seal therebetween in the manner described herein.

The drive shaft80includes the actuator engagement stem91disposed at a first end thereof and the disc engagement stem92disposed at an opposing second end thereof. As shown partially schematically inFIG.6, the actuator engagement stem91extends outside of the cover63for engagement with a corresponding structure of a rotary actuator150configured to selectively rotate the drive shaft80about the axis of rotation thereof. More specifically, the engagement stem91is shown as having an axially non-symmetric actuator engagement portion having a shape configured to mate with a correspondingly shaped axially non-symmetric opening (not shown) of the rotary actuator150for transferring torque from the rotary actuator150to the drive shaft80. However, it should be readily understood that any form of mechanical connection facilitating the selective rotation of the drive shaft80via actuation of the rotary actuator150may be utilized while remaining within the scope of the present invention. The rotary actuator150may be any form of rotary actuator150suitable for providing the torque necessary to cause the rotation of the rotary disc40relative to the fixed disc20via a transfer of the rotation of the drive shaft80to the rotary disc40. The rotary actuator150may be a torque motor, a servo motor, an electric stepper motor, or a brushless DC motor, as non-limiting examples.

An outer circumferential surface of the disc engagement stem92includes a cross-sectional shape substantially corresponding to that of the inner circumferential surface of the shaft receiving opening48of the rotary disc40to allow the disc engagement stem92to extend through the rotary disc40in an axially non-symmetric manner facilitating a transfer of rotation of the drive shaft80about the axis of rotation thereof to the rotary disc40such that the drive shaft80and the rotary disc40rotate in unison and maintain the same structural configuration relative to one another during rotation of the drive shaft80. However, there may be a slight clearance present between the facing inner and outer circumferential surfaces of the drive shaft80and the rotary disc40to allow for some limited play therebetween to accommodate any minor axial misalignments thereof, as desired.

As shown inFIG.4, the drive shaft80includes a central shaft81and a flow control wall82extending radially outwardly from an outer circumferential surface of the central shaft81at a position intermediate the actuator engagement stem91and the disc engagement stem92thereof. More specifically, the flow control wall82includes a first end83where the flow control wall82extends radially outwardly from the outer circumferential surface of the central shaft81at a position immediately adjacent an inwardly facing surface of the cover63disposed at an axial end of the opening67. The previously described annular shoulder65may be formed at the first end83of the flow control wall82. The flow control wall82extends away from the first end83thereof in an axial direction of the drive shaft80towards the second end62of the valve housing60, and the flow control wall82terminates at a second end84thereof. The flow control wall82also extends radially outwardly along at least one tapered segment thereof as the flow control wall82progresses axially from the first end83to the second end84thereof to cause the second end84to correspond substantially in shape and size to the rotary disc40about a perimeter of the second end84. The second end84of the flow control wall82is configured to be planar in configuration and to face towards (and in some embodiments engage) the first face41of the rotary disc40about the perimeter thereof. The flow control wall82accordingly forms a skirt-like structure depending from the central shaft81of the drive shaft80and expanding radially outwardly from the outer circumferential surface of the central shaft81to a perimeter shape substantially corresponding to that of the rotary disc40.

The flow control wall82includes an outer surface85facing towards the inner circumferential surface70of the circumferential wall68and an inner surface86facing towards the axis of rotation of the drive shaft80, which in the present embodiment corresponds to facing towards an interior disposed segment of the outer circumferential surface of the central shaft81. The outer surface85is divided into a circumferential flow surface87and an axial flow surface88. The circumferential flow surface87may be formed by substantially axially-symmetric surfaces, such as the illustrated cylindrical and frustoconical surfaces forming the circumferential flow surface87in the present figures, that are indented radially inwardly relative to the inner circumferential surface70of the circumferential wall69to allow for either of the first or the second fluid to flow circumferentially around an exterior of the flow control wall82when flowing towards the axial flow surface88. The axial flow surface88includes a first radial surface of the flow control wall82extending radially inwardly from a first end of the circumferential flow surface87, a second radial surface of the flow control wall82extending radially inwardly from an opposing second end of the circumferential flow surface87, and an exterior disposed segment of the outer circumferential surface of the drive shaft80disposed between the first and second radial surfaces. The axial flow surface88is indented radially inwardly relative to the circumferential flow surface87to promote a flow of the first or second fluid from flowing circumferentially around the circumferential flow surface87to flowing axially along and past the axial flow surface88. The axial flow surface88may be indented to include the same cross-sectional shape as the outer flow passage47of the rotary disc40. That is, the axial flow surface88may be indented to result in the formation of an axial flow pathway89at the second end84of the flow control wall82between the axial flow surface88and the inner circumferential surface70having the shape of a radially inwardly truncated sector of a circle in similar fashion to each of the flow openings31,32,33and the outer flow passage47. The axial flow pathway89may extend angularly around the axial direction of the drive shaft80about 120° to correspond to about a third of a cross-section of the opening67at the axial position of the second end84of the flow control wall82. The axial flow pathway89of the drive shaft80may be shaped and dimensioned to substantially correspond in shape and size to one of the flow openings31,32,33, and/or one of the apertures67b,67b,67c, and/or the outer flow passage47.

The flow chamber95integrated into the drive shaft80is defined by the inner surface86of the flow control wall82and extends circumferentially around the axis of rotation of the drive shaft80about 240° to correspond to about two-thirds of the cross-section of the opening67at the axial position of the second end84of the flow control wall82. A shape and size of the flow chamber95at the second end84of the flow control wall82may substantially correspond to a shape and size of the inner flow passage49of the rotary disc40. In the present embodiment, the flow chamber95is also partially defined by an interior disposed segment of the outer circumferential surface of the drive shaft80, but such a configuration is not necessary to prescribe the desired flow through the flow chamber95in accordance with the present disclosure. The flow chamber95tapers outwardly from a minimized radius at the first end83of the flow control wall82to a maximized radius at the second end84in accordance with the outward tapering of the inner surface86towards the second end84.

As can be seen throughoutFIGS.6-9, a combined flow area through the opening67between the outer surface85of the flow control wall82and the inner circumferential surface70of the valve housing60to each of the opposing sides of the flow control wall82, with respect to a circumferentially flowing fluid that is divided to flow around the flow control wall82in each of two opposing circumferential directions, may be substantially similar or equal to a flow area through the flow chamber95between the inner surface86of the flow control wall82and the outer circumferential surface of the central shaft81, similarly with respect to a circumferential flowing fluid, but only a single flow in a single circumferential direction. That is, the flow control wall82is tapered between the first and second ends83,84thereof to result in a divided flow of the fluid through two relatively smaller and diametrically opposing portions of the opening67disposed around the flow control wall82that is substantially equal to a single flow of the fluid through a relatively larger flow chamber95of the flow control wall82.

The use of such similar flow areas may beneficially result in the rotary valve10having a substantially similar effect with regards to a pressure drop experienced when one of the first fluid or the second fluid switches from flowing around the flow control wall82to flowing within the flow chamber95defined by the flow control wall82. That is, neither of the possible flow paths for either of the fluids relative to the drive shaft80includes an excessive expansion or constriction of flow therethrough relative to the other, hence neither of the possible flow paths is expected to have an unusually noticeable impact on the characteristics of the fluid flowing therethrough in comparison to the other possible flow path. The rotary valve10may accordingly be operable in any of a number of different flow configurations without the switching between such flow configurations resulting in an undesirably large drop in pressure of one of the corresponding fluids when switching from one flow configuration to another as facilitated by the structure of the disclosed rotary valve10. In some embodiments, a circumferential flow area through the flow chamber95may be about 90-110% of a circumferential flow area around an exterior of the flow control wall82along two opposing cylindrical segments of the inner circumferential surface70. In other embodiments, a circumferential flow area through the flow chamber95may be about 80-120% of a circumferential flow area around an exterior of the flow control wall82along two opposing cylindrical segments of the inner circumferential surface70. In yet other embodiments, a circumferential flow area through the flow chamber95may be about 70-130% of a circumferential flow area around an exterior of the flow control wall82along two opposing cylindrical segments of the inner circumferential surface70.

The biasing seal55is disposed axially between the second end84of the flow control wall82and the first face41of the rotary disc40. In the illustrated embodiment, the biasing seal55is disposed directly between the second end84of the flow control wall82and the first face41of the rotary disc40such that the flow control wall82and the rotary disc40are not in direct contact with one another, but are instead engaging and compressing opposing faces of the biasing seal55. In other embodiments, the biasing seal55may be disposed within a seal retaining groove (not shown) indented axially into the planar second end84of the flow control wall82or axially into the first face41of the rotary disc40. When received in such a seal retaining groove, the biasing seal55may include any suitable cross-sectional shape so long as the biasing seal55is dimensioned axially to include an axial height that is greater than an axial height of the seal retaining groove, thereby ensuring compression of the biasing seal55despite contact being present between the flow control wall82and the rotary disc40. The biasing seal55is shown inFIG.1as having the same configuration as the first face41of the rotary disc40on which the biasing seal55rests, hence the biasing seal55defines the same flow openings therethrough and therearound as described with reference to the rotary disc40. The biasing seal55is accordingly positioned to always be compressed axially between the second end84and the first face41about a perimeter of the inner flow passage49formed through the rotary disc40while fluidly separating the inner flow passage49from the outer flow passage47. The biasing seal55forms a fluid-tight seal between the flow control wall82and the rotary disc40preventing the flow of a fluid therebetween.

The biasing seal55also performs a secondary function in that the biasing seal55aids in maintaining a desired sealing force between the first face23of the fixed disc20and the second face42of the rotary disc40. The biasing seal55may be formed from an elastomeric or otherwise resiliently compressible material capable of applying a reactive force to each of the drive shaft80and the rotary disc40in the outward axial directions of the biasing seal55in reaction to the biasing seal55being compressed and elastically deformed in the inward axial directions thereof. The biasing seal55is configured to be normally compressed between the flow control wall82, which may be formed integrally (monolithically) with the remainder of the drive shaft80, and the first face41of the rotary disc40when the drive shaft80is in an installed operational position relative to the corresponding rotary actuator150. This normally occurring inward compression of the biasing seal55in the axial direction of the drive shaft80results in the biasing seal55applying an axially extending reactive force in a direction towards the rotary disc40, which in turn causes the second face42of the rotary disc40to be normally in contact with and sealingly engaging the first face23of the fixed disc20, which is in turn delimited from further axial motion by the axial end wall68of the valve housing60.

The normal compression of the biasing seal55in the axial direction accordingly results in an ability to maintain the desired sealing contact force between the opposing faces23,42in the absence of the need for an additional spring or other biasing element normally pressing against the flow control wall82in an axial direction towards the fixed disc20, such as disposing a normally compressed spring between the cover63and a facing surface of the flow control wall82, or another flanged or otherwise radially extending surface of the drive shaft80. However, the present invention is not necessarily limited to the use of the biasing seal55, as a spring or other biasing element as described may be utilized in the described configuration without necessary departing from the scope of the present invention. If such a spring is utilized, the biasing seal55may not be necessary to form the seal between the flow control wall82and the rotary disc40, and such components may instead be removably or non-removably joined to one another, or integrally (monolithically) formed with one another, to include the same structure as disclosed by the assembly of the drive shaft80and the rotary disc40.

The flow chamber95formed within the flow control wall82is configured to always be axially aligned with and fluidly coupled to the inner flow passage49formed through the rotary disc40regardless of the rotational position of the rotatable assembly15comprising the drive shaft80, the rotary disc40, and the biasing seal55. The inner flow passage49of the rotary disc40is in turn configured to selectively fluidly couple the flow chamber95of the drive shaft80with a corresponding pair of the three flow openings31,32,33formed through the fixed disc20, depending on the instantaneous rotational position of the rotatable assembly15according to the modes of operation disclosed with respect to the present invention. Each of the pairs of the flow openings31,32,33aligned with the inner flow passage49is in turn associated with a corresponding pair of the apertures67b,67c,67dleading to one of the inlets/outlets16b,18a,18b, hence the inner flow passage49of the rotary disc40may be said to fluidly couple the flow chamber95to a pair of the apertures67b,67c,67dor to a pair of the inlets/outlets16b,18a,18b.

The outer flow passage47of the rotary disc40is configured to always be fluidly coupled to a portion of the opening67disposed radially outwardly of the flow control wall82, whether by way of the circumferential flow surface87or the axial flow surface88of the flow control wall82, to cause the outer flow passage47to always be fluidly coupled to the outer surface85of the flow control wall82, the aperture67a, and the corresponding first inlet16a. The axial flow pathway89disposed radially outwardly of the flow control wall82at the boundary between the second end84thereof and the first face41of the rotary disc40may also be said to always fluidly couple the outer flow passage47of the rotary disc40to the outer surface85, the aperture67a, and the corresponding first inlet16a. The outer flow passage47is also configured to fluidly couple the flow space disposed between the flow control wall82and the circumferential wall69to one of the flow openings32,33corresponding to one of the outlets18a,18b, depending on the selected mode of operation of the rotary valve and the corresponding rotational position of the rotatable assembly15relative to the fixed disc20and the valve housing60.

The rotary valve10generally operates as follows. The rotary actuator150is configured to control the rotational position of the drive shaft80relative to the valve housing60and the fixed disc20via an appropriate transfer of torque from the rotary actuator150to the actuator engagement stem91of the drive shaft80. The drive shaft80rotates in a desired rotational direction as a result of the transfer of the torque thereto, and the rotation of the drive shaft80results in a further transfer of torque from the drive shaft80to the rotary disc40as a result of the axially non-symmetric rotational interference coupling provided therebetween. The rotatable assembly15is accordingly driven to rotate relative to the fixed disc20and the valve housing60to position the flow chamber95and the inner flow passage49in selective fluid communication with a corresponding pair of the flow openings31,32,33while the outer flow passage47and the axial flow pathway89are positioned in selective fluid communication with the remaining one of the flow openings31,32,33not forming the pair instantaneously aligned with the flow chamber95and the inner flow passage49.

FIGS.6and7illustrate the rotary valve10according to a first mode of operation whileFIGS.8and9illustrate the rotary valve10according to a second mode of operation. The different modes of operation including a switching of which of the first and second inlets16a,16bis in selective fluid communication with the respective first and second outlets18a,18b, thereby resulting in two possible modes of operation (assuming the use of two dedicated inlets and two dedicated outlets, as opposed to a bi-directional flow configuration). The first mode of operation includes the rotatable assembly15having the same configuration relative to the valve housing60as is disclosed in the exploded view ofFIG.1, wherein the flow chamber95and the inner flow passage49are axially aligned with the first and second flow openings31,32while the outer flow passage47and the axial flow pathway89are axially aligned with the remaining third flow opening33. The second mode of operation includes the rotatable assembly15being rotated about 120° in what would be the clockwise direction from the slightly overhead perspective ofFIG.1to reposition the flow chamber95and the inner flow passage49to be axially aligned with the first and third flow openings31,33while the outer flow passage47and the axial flow pathway89are axially aligned with the second flow opening32. The first mode of operation may be said to correspond to a first rotational position of the rotatable assembly15and the second mode of operation may be said to correspond to a second rotational position of the rotatable assembly15, wherein a switching between the modes of operation corresponds to a switching between the first and second rotational positions of the rotatable assembly relative to the valve housing60and the fixed disc20. ThroughoutFIGS.6-9, a flow of a first fluid originating from the first inlet16ais shown in broken-line arrows while a flow of a second fluid originating from the second inlet16bis shown in solid-line arrows to more easily distinguish the two separate fluid flows.

As shown inFIGS.6and7, the first mode of operation includes the first fluid flowing from the interior of the first inlet16aacross the aperture67aand into the opening67of the valve housing60while flowing in a direction perpendicular to the axial direction of the drive shaft80and/or valve housing60. The flow of the first fluid flows circumferentially through the opening67around the flow control wall82at positions disposed between the circumferential flow surface87and the inner circumferential surface70of the circumferential wall69before flowing axially along the axial flow surface88towards the axial flow pathway89. The flow of the first fluid flows axially across the axial flow pathway89at the second end84of the flow control wall82, through the outer flow passage47formed radially between the rotary disc40and the inner circumferential surface70, through the third flow opening33of the fixed disc20, and then through the aperture67dto enter the second outlet18b. The described pathway of the first fluid during the first mode of operation may be referred to as the first pathway through the rotary valve10.

The first mode of operation further includes the second fluid flowing from the interior of the second inlet16bacross the aperture67band into the first flow opening31of the fixed disc20while flowing axially towards the first end61of the valve housing60. The second fluid then flows axially through the inner flow passage49of the rotary disc40towards the first end61of the valve housing60before entering the flow chamber95integrated into the drive shaft80. The second fluid flows circumferential within the flow chamber95before flowing axially towards the second end62of the valve housing60through the inner flow passage49of the rotary disc40, the second flow opening32of the fixed disc20, and the aperture67ccorresponding to the first outlet18a. The flow chamber95accordingly forms an axial turn-around section of the flow path for the second fluid where the second fluid changes axial flow directions while also flowing circumferentially around the axis of rotation of the drive shaft80. It should be apparent that at least a portion of the second fluid may flow circumferentially through the inner flow passage49while bypassing flow through the flow chamber95due to the inner flow passage49extending circumferentially along the same angular displacement as the flow chamber95while always in fluid communication therewith. The described pathway of the second fluid during the first mode of operation may be referred to as the second pathway through the rotary valve10.

As shown inFIGS.8and9, the second mode of operation includes the first fluid flowing from the interior of the first inlet16aacross the aperture67aand into the opening67of the valve housing60while flowing in a direction perpendicular to the axial direction of the drive shaft80and/or valve housing60. The flow of the first fluid flows circumferentially through the opening67around the flow control wall82at positions disposed between the circumferential flow surface87and the inner circumferential surface70of the circumferential wall69before flowing axially along the axial flow surface88towards the axial flow pathway89. The flow of the first fluid flows axially across the axial flow pathway89at the second end84of the flow control wall82, through the outer flow passage47formed radially between the rotary disc40and the inner circumferential surface70, through the second flow opening32of the fixed disc20, and then through the aperture67cto enter the first outlet18a. The described pathway of the first fluid during the second mode of operation may be referred to as the third pathway through the rotary valve10.

The second mode of operation further includes the second fluid flowing from the interior of the second inlet16bacross the aperture67band into the first flow opening31of the fixed disc20while flowing axially towards the first end61of the valve housing60. The second fluid then flows axially through the inner flow passage49of the rotary disc40towards the first end61of the valve housing60before entering the flow chamber95integrated into the drive shaft80. The second fluid flows circumferential within the flow chamber95before flowing axially towards the second end62of the valve housing60through the inner flow passage49of the rotary disc40, the third flow opening33of the fixed disc20, and the aperture67dcorresponding to the second outlet18b. It should once again be apparent that at least a portion of the second fluid may flow circumferentially through the inner flow passage49while bypassing flow through the flow chamber95due to the inner flow passage49extending circumferentially along the same angular displacement as the flow chamber95while always in fluid communication therewith. The described pathway of the second fluid during the second mode of operation may be referred to as the fourth pathway through the rotary valve10.

The first mode of operation accordingly includes the first fluid flowing from the first inlet16ato the adjacent disposed and perpendicular arranged second outlet18band the second fluid flowing from the second inlet16bto the adjacent disposed and perpendicular arranged first outlet18a. In contrast, the second mode of operation includes the first fluid flowing from the first inlet16ato the diametrically opposing and parallel arranged first outlet18aand the second fluid flowing from the second inlet16bto the diametrically opposing and parallel arranged second outlet18b.

The integration of the flow chamber95into the drive shaft80beneficially reduces a part count and complexity of manufacturing the rotary valve10. The formation of the flow chamber95directly in the structure of the drive shaft80also beneficially facilitates an enlargement of the flow area through the flow chamber95to prevent the flow chamber95forming an undesirable flow restriction to the fluid passing therethrough. The disclosed configuration also facilitates the use of the biasing seal55in place of a spring or other biasing element, while the seal55also provides the necessary sealing to prevent a mixing between the different flows paths formed through the rotary valve10.

Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms, and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. Equivalent changes, modifications and variations of some embodiments, materials, compositions and methods can be made within the scope of the present technology, with substantially similar results.