HK1244525B - Stator - Google Patents

Description

stator

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a PCT international application claiming priority to U.S. Patent Application No. 14/931,885, filed on November 4, 2015, and to U.S. Provisional Patent Application No. 62/156,512, filed on May 4, 2015.

Technical Field

The disclosed and claimed concept relates to a stator assembly for a progressive cavity pump, and more particularly to a stator assembly in which the spiral passage is a flexible spiral passage.

Background Art

Progressive cavity pumps are often referred to as "Moineau" pumps in recognition of their inventor, Rene Moineau (who received U.S. Patent No. 1,892,217). Progressive cavity pumps are used in various industries to pump materials such as, but not limited to, viscous fluids, semi-solids, fluids with suspended solids, and solids. Exemplary materials transported by progressive cavity pumps include, but are not limited to, oil, sewage, fracturing fluids, and the like. Typically, a progressive cavity pump (also known as a helical gear pump) includes an elongated rotor having one or more externally threaded helical lobes or "splines" that are rotatably disposed in a stator assembly or stator body that defines a helical channel. In one embodiment, the helical channel includes one more lobe than the helical rotor. The elongated helical channel includes a plurality of spiral grooves that form a plurality of cavities with the stator. As the rotor rotates within the stator, the cavities advance from the suction end of the pump to the discharge end. In other embodiments, there are the same number of rotor splines and stator lobes, but the rotor splines are sized and shaped so as to define a cavity within the stator lobe. In an exemplary embodiment, in theory, each lobe of the rotor is always in substantial contact with the stator at any cross-section; this has the effect of creating a plurality of empty spaces between the stator and the rotor. It is noted that the clearance or interference at locations where the rotor splines do not fully seat in the stator lobe can be variable, i.e., less than substantial engagement. That is, for example, in embodiments where the stator channels have arcuate end surfaces and linear side surfaces, it is desirable to ensure that the rotor seals against the arcuate end surfaces of the stator; this ensures that the cavity, and therefore the fluid therein, moves forward. Sealing of the rotor against the linear side surfaces of the stator is desirable but less critical.

As the rotor rotates, the empty space advances from the suction end of the spiral channel to the discharge end of the spiral channel. Furthermore, the empty spaces are isolated from one another by contact points between the rotor and stator, often referred to as "seal lines." As the rotor rotates within the stator, the empty space "moves," or advances, in a spiral motion along the length of the spiral channel. During operation of a progressive cavity pump, the empty space fills with material to be moved. Thus, as the empty space advances, material moves from one end of the stator to the other as the rotor rotates relative to the stator. Due to the shape and geometry of the stator and rotor, as the rotor rotates within the stator, it will move laterally, or precess, relative to the stator. In other words, in addition to rotating within the stator, the rotor moves eccentrically relative to the stator.

In the exemplary embodiment shown in FIG1 , a progressive cavity pump 1 includes an elongated helical rotor 2 and a stator assembly 3 defining an elongated helical channel 4. In the exemplary embodiment shown, the rotor has a single lobe and, therefore, a generally circular cross-sectional shape. The helical channel (shown in cross-section) has an oblong shape. As used herein, an "oblong" shape includes opposing generally arcuate surfaces and opposing generally parallel, generally linear surfaces; it can be colloquially identified as a "pill" shape. In operation, the rotor 2 reciprocates between the ends of the helical channel.

To ensure that the rotor is always in substantial contact with the stator at any cross-section, the stator's spiral channel is typically lined with a resilient material, such as, but not limited to, an elastomeric material. Specifically, in exemplary embodiments, the stator assembly includes a rigid support assembly defining the spiral channel, and the lining is disposed thereon. In the exemplary embodiment shown in FIG1 , as the rotor rotates and reciprocates between the ends of the spiral channel, the resilient material is compressed between the rotor and the support structure. Furthermore, if the material being moved is a fluid containing suspended solids, the solids may pass between the resilient material and the rotor.

This construction has several disadvantages, including the degradability of the elastomeric liner. That is, compression of the elastomeric liner results in rapid wear and tear on the liner, resulting in the need for replacement. As used herein, "rapid" degradation is a relative term; elastomeric materials degrade faster than durable materials. In addition, solids passing between the elastomeric material and the rotor can also damage the elastomeric liner. Additionally, the elastomeric liner can react with or be degraded by the material being moved. Another disadvantage is that the rigid stator assembly is difficult and/or expensive to construct. That is, such stator assemblies are typically formed by hydroforming, rolling metal tubes, cold drawing metal tubes, hot extruding metal tubes, drilling metal tubes using methods such as, but not limited to, electrical discharge machining, and electroforming using metal deposition.

In another embodiment, not shown, the stator assembly is substantially made of an elastic material. Although the elastic material can have a rigid shell, the spiral structure and support members are formed of an elastic material. This embodiment also allows for substantially constant contact between the rotor and stator assembly and allows solids to pass between the rotor and stator. However, this embodiment is also subject to rapid degradation. In addition, because the stator spiral channel is generally elastic, the progressive cavity pump of this embodiment is limited to lower pressures and lower transfer speeds. In other words, under higher pressures, the stator will deform, allowing material to flow back onto the rotor.

In another embodiment, not shown, the stator assembly is made of a rigid material without an inner liner. Typically, both the rotor and stator are made of a durable material (i.e., a non-elastic material). While durable materials are less susceptible to wear and tear, friction between the two durable material elements will cause wear and tear on both the rotor and stator. Furthermore, when both the rotor and stator are made of rigid materials, particles cannot pass between them. In other words, solids trapped between the rigid rotor and stator will be crushed, causing additional wear and tear on the components. Alternatively, in the case of larger or more durable particles, the rotor will bend, potentially permanently bending the rotor. Similarly, and as used herein, a progressive cavity pump in which a durable rotor engages or moves on a durable stator is a "self-damaging" progressive cavity pump. One solution to the particle problem in self-damaging progressive cavity pumps is to allow a small gap between the rotor and stator; that is, the rotor and stator are not "always in contact." However, this configuration allows for backflow of material between adjacent cavities. In other words, this configuration is less efficient. Furthermore, in this embodiment, the stator is typically manufactured by one of the expensive methods mentioned above.

Furthermore, as noted in U.S. Patent No. 8,905,733, there are advantages to having turbulent flow of fluid adjacent to the stator surface within a progressive cavity pump. In that patent, turbulence is generated or enhanced by grooves in, for example, the surface of the stator's spiral channel. However, these grooves must be machined into the stator's spiral channel surface during or sometimes after the channel is formed. Similarly, the grooves are expensive to incorporate into the stator.

It will be appreciated that a progressive cavity pump comprises a drive assembly having a drive shaft that causes a rotor to rotate within a stator, thereby producing a pumping action. That is, the rotational motion is converted into fluid motion, i.e., pumping. However, as is known, rotor/stator assemblies with smaller geometric differences can have a fluid pumped through them, causing the rotor to rotate. This motion is then transmitted to the drive shaft and drive assembly. That is, the fluid motion is converted into mechanical motion. Therefore, it will be appreciated that although the following discussion refers to the rotor/stator assembly as a pump, the same rotor/stator assembly can be used to produce rotational motion, i.e., it can be used as a drive device, such as for drilling.

Therefore, there is a need for an improved progressive cavity pump in which the components do not experience rapid degradation, do not self-destruct, and do not allow backflow of the material being transported.

Summary of the Invention

These needs and others are achieved by the disclosed and claimed concept, which provides a stator assembly for a progressive cavity pump, the stator assembly comprising a plurality of stator laminations having a planar body defining a primary inner channel and a plurality of outer channels, the outer channels being arranged operatively adjacent to the inner channels, whereby the inner channels are at least partially defined by an annulus, wherein the annulus is outwardly flexible. The stator laminations are coupled to one another in a stacked arrangement, wherein the inner channels of the stator lamination body define a spiral channel. The spiral channel is a flexible, helical channel.

It is noted that the construction proposed below, including the choice of materials, solves the problems described.

BRIEF DESCRIPTION OF THE DRAWINGS

A complete understanding of the present invention can be obtained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings, in which:

FIG1 is a partial cross-sectional side view of a prior art progressive cavity pump.

2 is a schematic side view of a progressive cavity pump.

3 is an isometric fragmentary view of the rotor assembly and the stator assembly.

4 is a partial elevational view of a rotor assembly and a stator assembly including a slider of a progressive cavity pump.

FIG5 is a front view of a stator lamination body of a stator assembly.

6 is an exploded isometric fragmentary view of a stator lamination stack of a stator assembly.

DETAILED DESCRIPTION

It should be understood that the specific elements shown in the drawings herein and described in the following specification are merely exemplary embodiments of the disclosed concepts and are provided for illustrative purposes only as non-limiting examples. Therefore, specific dimensions, orientations, components, number of parts used, embodiment configurations, and other physical characteristics related to the embodiments disclosed herein should not be construed as limiting the scope of the disclosed concepts.

Directional phrases used herein (such as, for example, clockwise, counterclockwise, left, right, top, bottom, upward, downward, and derivatives thereof) refer to the orientation of elements shown in the drawings and do not limit the claims unless explicitly recited herein.

As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

As used herein, a statement that two or more parts or components are "coupled" shall mean that the parts are joined together or operate together, directly or indirectly (i.e., through one or more intermediate parts or components), as long as a connection occurs. As used herein, "directly coupled" means that two elements are in direct contact with each other. It should be noted that a moving part (such as, but not limited to, a circuit breaker contact) is "directly coupled" when it is in one position (e.g., a closed second position), but not "directly coupled" when it is in an open first position. As used herein, "fixedly coupled" or "fixed" means that two parts are coupled so as to move as a whole while maintaining a constant orientation relative to each other. Therefore, when two elements are coupled, all parts of these elements are coupled. However, a description that a specific part of a first element is coupled to a second element (e.g., a first shaft end is coupled to a first wheel) means that the specific part of the first element is arranged closer to the second element than other parts.

As used herein, the phrase "removably coupled" means that one component is coupled to another component in a substantially temporary manner. That is, the two components are coupled in such a manner that joining or separating the components is easy and will not damage the components. For example, two components that are secured to each other using a limited number of easily accessible fasteners are "removably coupled," while two components that are welded together or joined by inaccessible fasteners are not "removably coupled." An "inaccessible fastener" is a fastener that requires the removal of one or more other components before accessing the fastener, where the "other components" are not access devices, such as, but not limited to, a door.

As used herein, "operably coupled" means that a plurality of elements or components, each movable between a first position and a second position or a first configuration and a second configuration, are coupled such that when the first element is moved from one position/configuration to another, the second element also moves between the positions/configurations. Note that a first element can be "operably coupled" to another element while the reverse is not true.

As used herein, a "coupling assembly" includes two or more couplings or coupling components. A coupling or component of a coupling assembly is generally not part of the same element or other component. Likewise, in the following description, components of a "coupling assembly" may not be described simultaneously.

As used herein, a "coupling" or "coupling component" is one or more components of a coupling assembly. That is, a coupling assembly includes at least two components that are configured to couple together. It should be understood that the components of a coupling assembly are compatible with one another. For example, in a coupling assembly, if one coupling component is a snap-on receptacle, the other coupling component is a snap-on plug, or if one coupling component is a bolt, the other coupling component is a nut.

As used herein, "corresponding" means that the size and shape of two structural components are designed to be similar to each other and can be coupled with a minimum amount of friction. Thus, an opening that "corresponds" to a component is slightly larger than the component so that the component can pass through the opening with a minimum amount of friction. This definition is modified if the two components are to fit together "tightly." In this case, the difference between the sizes of the components is even smaller, thereby increasing the amount of friction. If the elements defining the opening and/or the components inserted into the opening are made of a deformable or compressible material, then the opening can even be slightly smaller than the components inserted into the opening. In terms of surfaces, shapes, and lines, two or more "corresponding" surfaces, shapes, or lines have substantially the same size, shape, and contour.

As used herein, in the phrase “[x] moves between its first position and its second position” or “[y] is configured to move [x] between its first position and its second position,” “[x]” is the name of an element or component. Furthermore, when [x] is the element or component that moves between positions, the pronoun “its” means “[x],” that is, the named element or component preceding the pronoun “its.”

As used herein, in the phrase "[x (first element)] moves between a first position and a second position corresponding to the first position and the second position of [y (second element)]," where "[x]" and "[y]" are elements or components, the word "corresponding" means that when element [x] is in the first position, element [y] is in the first position, and when element [x] is in the second position, element [y] is in the second position. Note that "corresponding" is relative to the final positions and does not mean that the elements must move at the same speed or simultaneously. That is, for example, a hubcap and a wheel to which it is attached rotate in a corresponding manner. Conversely, a spring-biased latch member and a latch release move at different rates. Thus, as described above, "corresponding" positions mean that the elements are simultaneously in the identified first position and simultaneously in the identified second position.

As used herein, the statement that two or more parts or components "engage" one another shall mean that the elements apply a force or bias against one another, either directly or through one or more intermediate elements or components. Furthermore, as used herein with respect to a moving part, the moving part may "engage" another element during movement from one position to another and/or may "engage" another element once in the described position. Thus, it will be understood that the statements "element A engages element B when element A moves to element A's first position" and "element A engages element B when element A is in element A's first position" are equivalent statements and mean that element A engages element B when moved to element A's first position and/or element A engages element B when in element A's first position.

Furthermore, as used herein, a moving element or a surface on a moving element may "generally engage" another element along a path of travel, or may "substantially engage" another element along a path of travel. As used herein, "generally engage" means that along the path of travel, the moving element or the surface on the moving element generally applies a force or bias against the other element, but there are points along the path of travel where the force or bias is not applied against the other element. As used herein, "substantially engage" means that along the path of travel, the moving element or the surface on the moving element substantially applies a force or bias against the other element, without any significant point along the path of travel where the force or bias is not applied against the other element.

As used herein, "operably engaged" means "engage and move." That is, when used with respect to a first component configured to move a movable or rotatable second component, "operably engaged" means that the first component applies a force sufficient to cause the second component to move. For example, a screwdriver can be placed in contact with a screw. When no force is applied to the screwdriver, the screwdriver is merely "coupled" to the screw. If an axial force is applied to the screwdriver, the screwdriver is pressed against the screw and "engages" the screw. However, when a rotational force is applied to the screwdriver, the screwdriver is "operably engaged" with the screw and causes the screw to rotate.

As used herein, the term "unitary" refers to a component that is formed as a single member or unit. That is, a component that includes components that are formed separately and then coupled together as a unit is not a "unitary" component or body.

As used herein, "configured to [verb]" means that the identified element or component has a structure that is shaped, sized, arranged, coupled and/or configured to perform the identified verb. For example, a member that is "configured to move" is movably coupled to another element and includes an element that causes the member to move, or the member is otherwise configured to move in response to the other element or component. Likewise, as used herein, "configured to [verb]" states structure rather than function. Furthermore, as used herein, "configured to [verb]" means that the identified element or component is intended and designed to perform the identified verb. Therefore, an element that is only capable of performing the identified verb but is not intended and designed to perform the identified verb is not "configured to [verb]."

As used herein, "associated" means that elements are part of the same assembly and/or operate together, or act on/interact with each other in some manner. For example, a car has four tires and four hubcaps. Although all elements are coupled as part of the car, it should be understood that each hubcap is "associated" with a specific tire.

As used herein, a "planar body" or "planar member" is a generally thin element that includes opposing, wide, generally parallel surfaces and thinner edge surfaces extending between the wide parallel surfaces. The periphery and therefore the edge surfaces may include generally straight portions (e.g., as on a rectangular planar member), or may be curved (e.g., as on a disk) or have any other shape. Furthermore, a "monolithic planar member" includes all portions of a construction that are generally arranged in a similar plane. That is, for example, a flat single sheet of paper is a single "monolithic planar member," rather than two or more planar members arranged adjacent to each other. In other words, a "monolithic planar member" extends between the edges of a generally planar construction, rather than a portion thereof. Thus, as used herein, in a layered construction comprising a monolithic body, each layer is a "planar member," wherein the planar member is divided by a plane extending generally parallel to the flat surfaces of the planar member. That is, each "planar member" is a portion of the construction that is between the edges of the layers.

As used herein, "around" used in the context of "disposed around [an element or axis]" or "extending around [an element or axis]" means surrounding or extending around.

As used herein, "elastic" means flexible and deformable, and does not mean strong.

As used herein, an interface between two surfaces, a rotor assembly outer surface, a slider body edge surface, a stator assembly/body spiral channel, or a stator lamination body inner channel can be identified by one or two adjectives; i.e., [first adjective], [second adjective] stator assembly/body inner spiral channel, or [first adjective], [second adjective] stator lamination body inner channel. The adjectives describe the characteristics of at least one surface at the interface, the stator assembly/body inner spiral channel surface, or the stator lamination body inner channel surface. The first adjective is optional and describes the durability of the material, i.e., the material properties. The first adjective is selected from the group consisting of "durable," "robust," and "degradable." The second adjective describes the construction of the stator assembly, i.e., the construction features. The second adjective is selected from the group consisting of "rigid," "flexible," "deformable," and "elastic."

As used herein, a "durable" material is a hard metal, alloy, or other composition having properties similar to hard metals, such as, but not limited to, steel, carbon steel, tool steel, fluorinated hydrocarbons and polymers sold by E.I. duPont de Nemours and Company, A2 tool steel, 17-4PH stainless steel, crucible steel, 4150 steel, 4140 steel, or 1018 steel, polished stainless steel, or virtually any stainless steel, carbon steel, or alloy steel. A "durable" material does not easily damage.

As used herein, a "robust" material is a rigid material that is less hard than hard metal or "durable" material and includes, but is not limited to, hard plastics and composite materials.

As used herein, a "degradable" material is a soft or easily damaged material, such as, but not limited to, an elastomeric material. It should be understood that "easily damaged" is a relative term used in comparison to a durable material.

As used herein, a "rigid" construction substantially maintains its shape when subjected to a bias or force; for example, a stator made of a hard metal is a stator having a "rigid" construction where the stator body is thick enough to prevent the metal from bending.

As used herein, a "flexible" configuration allows a portion of a surface to deflect when subjected to a bias or force, and does so without substantially deforming the localized portion of the surface. For example, a hard material supported by a spring provides a "flexible" configuration, wherein the surface of the hard material does not substantially deform when a bias is applied thereto, but the spring allows the surface to move/deflect. In a configuration in which a single body defines the surface and the spring, the "flexible" configuration allows deflection at the location where the bias is applied and deformation at locations remote from the location where the bias is applied, i.e., the spring element deforms at the point where the bias is applied rather than the surface.

As used herein, a "deformable" configuration substantially maintains its shape while allowing the surface to deform. For example, an elastomeric liner disposed on a rigid metal support provides a "deformable" surface because the rigid metal support maintains the shape of the liner, but the liner allows for localized compression upon application of a bias, i.e., deformation at the location where the bias is applied.

As used herein, a "resilient" construction is flexible and deformable. A stator assembly/body made substantially of an elastomeric material provides a "resilient" surface in that the body is generally flexible while also allowing localized deformation at the surface when a bias is applied.

Furthermore, as used herein, the specific adjectives for each group, i.e., [first adjective] (material property) and [second adjective] (construction property), are different. That is, as used herein, a single material cannot be both "durable" and "robust". Furthermore, as used herein, a material or construction that can be identified by one adjective cannot be "identified" by another adjective. For example, as used herein, a "deformable" construction cannot be a "flexible" construction; it is only a "deformable" construction. It should be noted that "degradable" materials such as, but not limited to, elastomeric materials can be constructed to be both "flexible" and "deformable" as described above. However, as described in this paragraph, a construction cannot be both "flexible" and "deformable", which is why "flexible" and "deformable" constructions have been defined by the separate adjective "elastic". That is, for example, as used herein, a body made of an elastomeric material is identified herein as an "elastic" construction and not as a "flexible" and "deformable" construction. Furthermore, the following example is provided for clarity. An elastomeric lining disposed on a metal support provides a degradable, deformable surface. That is, the surface is easily damaged, but cannot bend due to the metal support. The surface on the solid steel plate provides a durable, rigid surface. That is, steel is a durable material that substantially maintains its shape because the plate is not flexible or deformable.

The fluid transfer assembly 6 moves the fluid. In the exemplary embodiment, the fluid transfer assembly 6 utilizes a drive assembly 18 to move the fluid and is identified as a progressive cavity pump 10. However, as described above, the moved fluid can be used to rotate a driven assembly (not shown) that is typically coupled to a drill bit (not shown) and identified as a hydraulic motor (not shown). The progressive cavity pump 10 is used below as an example; however, it should be understood that the rotor assembly 20 and stator assembly 100 discussed below can also be used with a hydraulic motor.

Figure 2 schematically illustrates a progressive cavity pump 10. As is known, the progressive cavity pump 10 includes a housing assembly 12 defining an inlet 14 and an outlet 16. The progressive cavity pump 10 also includes a drive assembly 18 (which may be remote), a rotor assembly 20, and a stator assembly 100 defining an elongated spiral channel 104. That is, the stator assembly spiral channel 104 is elongated along the longitudinal axis of the stator assembly 100 and spirals around the longitudinal axis of the stator assembly. The spiral channel 104 includes a surface 105. Typically, as is known, both the inlet 14 and the outlet 16 are in fluid communication with the stator assembly spiral channel 104. The drive assembly 18 is operably coupled to the rotor assembly 20 and is configured to rotate the rotor assembly. The rotor assembly 20 is rotatably disposed in the stator assembly spiral channel 104. In an exemplary embodiment, the rotor assembly 20 includes an elongated spiral body 22 having an outer surface 23. The rotor assembly spiral body 22 is sized to contact the stator assembly spiral channel 104 along a seal line (not shown). The seal line divides the stator assembly spiral channel 104 into individual cavities. Rotation of the rotor assembly spiral body 22 causes the cavities to advance from the inlet 14 to the outlet 16, that is, from an "upstream" position to a "downstream" position as used herein. In other words, the "upstream" to "downstream" flow direction is in the direction from the inlet 14 to the outlet 16.

In an exemplary embodiment, the rotor assembly outer surface 23 and the stator assembly spiral channel surface 105 discussed below are made of durable materials. In addition, at least one of the rotor assembly 20 or the stator assembly 100 includes a flexible component 11. As used herein, the flexible component 11 is configured to provide a flexible surface on at least one of the engaging surfaces of the rotor assembly body 22 or the stator assembly spiral channel 104. As used herein, a "engaging surface" is a surface that meets, whereby the stator assembly spiral channel 104 is divided into a plurality of cavities. As shown in the figure, the "engaging surface" is a portion of the rotor assembly outer surface 23 or the stator assembly spiral channel surface 105.

In the exemplary embodiment, rotor assembly 20 includes an elongated spiral body 22. In this exemplary embodiment, rotor assembly body 22 is made of a durable material and is a single-piece body. Furthermore, in the illustrated embodiment, rotor assembly body 22 includes a single lobe and, therefore, has a generally circular cross-sectional shape. It should be understood that rotor assembly body 22 may include any number of lobes, wherein each lobe defines an elongated spiral portion of rotor assembly body 22. That is, each lobe defines a spiral element disposed about a common longitudinal axis 26. As described below, in the exemplary embodiment, stator assembly spiral channel 104 has one more lobe than rotor assembly body 22. However, as described above, other embodiments (not shown) include rotor assembly body 22 in which the rotor lobes are sized and shaped to define cavities within the stator lobes. In the illustrated exemplary embodiment, rotor assembly body 22 includes a single lobe; stator assembly spiral channel 104 has two lobes. That is, the dual-lobed stator assembly spiral channel 104 has an oblong cross-sectional shape. Furthermore, in the exemplary embodiment, rotor assembly body 22 has a substantially constant transverse (i.e., perpendicular to the axis of rotation) cross-sectional area from the upstream end to the downstream end. That is, at any selected longitudinal position along rotor assembly body 22, rotor assembly body 22 has substantially the same cross-sectional area as at another selected longitudinal position along rotor assembly body 22. In the exemplary embodiment, rotor assembly body 22 substantially engages the arcuate portion of spiral channel 104, while rotor assembly body 22 substantially engages the linear (or non-arc-shaped) portion of spiral channel 104. That is, sealing in the linear (or non-arc-shaped) portion of spiral channel 104 is less critical than sealing in the arcuate portion of spiral channel 104.

In another exemplary embodiment, the rotor assembly body 22 has a narrowing taper from the upstream end to the downstream end, i.e., a decreasing cross-sectional area. In another exemplary embodiment, the rotor assembly body 22 has a widening taper from the upstream end to the downstream end, i.e., an increasing cross-sectional area. It should be understood that the cross-sectional area of the stator assembly spiral channel 104 matches the cross-sectional area of the rotor assembly body 22, i.e., whether constant, narrowing, or widening. The rotor assembly body 22 is coupled, directly coupled, or fixed to the drive assembly 18, and the drive assembly 18 is configured to rotate the rotor assembly body 22.

In another exemplary embodiment, as shown in FIG3 , the rotor assembly 20 includes a "stacked" body 30 . That is, the rotor assembly stacked body 30 includes a "stack" of lamination bodies 32 , hereinafter referred to as "rotor lamination bodies 32 ." As used herein, a "lamination body" or "laminate" is a generally planar body and, in the exemplary embodiment, a unitary, planar body having a thickness between approximately 0.010 inches and 0.100 inches, or approximately 0.025 inches. As used herein, a "stack" or "stacked body" includes a plurality of lamination bodies arranged such that one lamination body planar surface abuts an adjacent lamination body planar surface. Thus, with the exception of the first and last lamination bodies in the "stack," each lamination body is positioned between two adjacent lamination bodies. The rotor lamination bodies 32 are coupled by any known method, including, but not limited to, riveting the rotor lamination bodies 32 , welding the outer surfaces of the rotor lamination bodies 32 , welding each rotor lamination body 32 to an adjacent rotor lamination body 32 , or mechanically compressing the rotor lamination bodies 32 . In this configuration, each rotor lamination body 32 has an edge 34 that extends generally parallel to the axis of rotation of the rotor assembly stack body 30. That is, the plane of the rotor lamination body edge 34 extends generally parallel to the axis of rotation of the rotor assembly stack body 30. As used herein, and with respect to a lamination body, "edge" includes a surface extending between two generally parallel planar surfaces. Furthermore, as with the embodiment of the unitary rotor assembly body 22, the cross-sectional area of the rotor assembly stack body 30 can be constant, narrowing, or widening as described above.

As described below, in an exemplary embodiment, the stator assembly 100 is also a stacked lamination assembly. In embodiments described below where the rotor assembly 20 includes a stacked body 30 and the stator assembly 100 includes a stator lamination body 110, each rotor lamination body 32 has substantially the same thickness as the associated stator lamination body 110.

In the exemplary embodiment, each rotor lamination body 32 has a first thickness. That is, each rotor lamination body 32 has a substantially similar thickness. In an alternative embodiment (not shown), the thickness of a rotor lamination body 32 may differ from the thickness of another rotor lamination body 32. For example, in an exemplary embodiment (not shown), each rotor lamination body 32 in a first set of rotor lamination bodies 32 has a first thickness, and each rotor lamination body 32 in a second set of rotor lamination bodies 32 has a second thickness. The rotor lamination bodies 32 of the groups may be arranged such that the first set of rotor lamination bodies 32 is located upstream of the second set of rotor lamination bodies 32. Alternatively, the first set of rotor lamination bodies 32 may be staggered with the second set of rotor lamination bodies 32. Note that additional groups of rotor lamination bodies 32 having different thicknesses may exist, and each group may include any number of rotor lamination bodies 32. In another embodiment, the laminations of a selected group may be "thick laminations," as defined below.

Furthermore, in another embodiment (not shown), the rotor lamination bodies 32 may be tapered in thickness or thinness. In this embodiment, the rotor lamination bodies 32 may comprise "thick laminations," as used herein, comprising a generally planar body, and in the exemplary embodiment, a unitary planar body having a thickness greater than approximately 0.010 inches. In this embodiment, the thickness of the rotor lamination bodies 32 (which have substantially the same thickness as the associated stator lamination bodies 110) is thicker at the downstream end of the rotor assembly body 22, where a larger cavity within the stator assembly spiral passage 104 is defined by a particular number of rotor lamination bodies 32. That is, for example, the cavity defined by ten rotor lamination bodies 32 at the downstream end of the rotor assembly body 22 is larger than the cavity defined by ten rotor lamination bodies 32 at the upstream end of the rotor assembly body 22. In this configuration, the pressure of the pumped fluid at the downstream end of the rotor assembly body 22 is different relative to the pressure at the upstream end of the rotor assembly body 22.

In another exemplary embodiment, as shown in FIG4 , the rotor assembly 20 includes a plurality of sliders 40, each of which includes the flexible assembly 11. The sliders 40 include a planar body 42, which is a lamination as defined above, thereby defining an elongated rotor body channel 44, and has a periphery 46 and an edge surface 48. In the exemplary embodiment, the slider body 42 is a single-piece body. Furthermore, in the exemplary embodiment, each slider body 42 has substantially the same thickness as the associated rotor lamination body 32 and stator lamination body 110. In this embodiment, the slider body edge surface 48 defines the rotor assembly body outer surface 23. As described below, the surface of the rotor body channel 44 defines a cam surface 45. In the exemplary embodiment in which the stator assembly spiral channel 104 has an oblong cross-sectional shape, each slider body 42 has an oblong shape corresponding to the oblong shape of the stator assembly spiral channel 104, but with a smaller longitudinal length. In the exemplary embodiment, the longitudinal axis of the rotor body channel 44 is substantially perpendicular to the substantially parallel, substantially linear surfaces of the slider body 42.

It is noted that in the exemplary embodiment, engagement of the opposing linear surfaces of the slider body 42 with the opposing linear surfaces of the oblong stator assembly spiral passage 104, while desirable, is less critical than engagement of the opposing arcuate surfaces of the slider body 42 with the opposing arcuate surfaces of the oblong stator assembly spiral passage 104. That is, the opposing linear surfaces of the slider body 42 generally engage the opposing linear surfaces of the oblong stator assembly spiral passage 104, while the opposing arcuate surfaces of the slider body 42 substantially engage the opposing arcuate surfaces of the oblong stator assembly spiral passage 104.

In an exemplary embodiment, each sliding body 42 includes a plurality of outer channels 50 that are arranged to be "effectively adjacent" to at least a portion of the sliding body periphery 46 and the sliding body edge surface 48. In an exemplary embodiment, the sliding body outer channels 50 extend around the sliding body periphery 46 and the sliding body edge surface 48. As described below, the sliding body outer channels 50 are configured to allow the sliding body edge surface 48 to be flexible. Therefore, as used herein, the "effectively adjacent" arrangement means that the opening is close enough to the sliding body periphery 46 to allow the sliding body edge surface 48 adjacent to the sliding body outer channels 50 to be flexible. It should be understood that the distance of "effectively adjacent" depends on the variables selected, including but not limited to the material properties of the sliding body 42, the size and shape of the sliding body outer channels 50, and the thickness of the sliding body 42.

In an exemplary embodiment, the sliding body 42 is made of a durable material or a strong material. Thus, as a non-limiting example, the first sliding body (not shown) is made of a durable material and has a thickness X, and the second sliding body (not shown) is made of a strong material and has a thickness X/2. In addition, on each of the first sliding body and the second sliding body, the sliding body outer channel (not shown) has the same size and shape. In this example, and in order to be "effectively adjacent" as used herein, the sliding body outer channel on the first sliding body will need to be closer to the first sliding body periphery (not shown) than the sliding body outer channel on the second sliding body in order to make the first sliding body edge surface (not shown) flexible. That is, it should be understood that durable materials are more rigid than strong materials, and therefore, in order for the durable material along the periphery of the first sliding body to become flexible, the first sliding body outer channel must be closer to the periphery of the first sliding body so that the "annulus" defined below is thinner. It is well known that thinner structures of the same material are more flexible than thicker structures.

In the exemplary embodiment, the slider body outer channels 50 are elongated slots 52 arranged in a concentric configuration. That is, there is a first set of slider body outer channels 60 (i.e., a "first set" is collectively identified by reference numeral 60) and a second set of slider body outer channels 62 (i.e., a "second set" is collectively identified by reference numeral 62). Each slider body slot 52 is an elongated opening having a first end 54, a middle portion 56, a second end 58, and a longitudinal centerline 59. In the exemplary embodiment, as shown, the slider body slots 52 are generally similar in size (i.e., length along the slider body slot longitudinal centerline 59). The slider body slots 52 generally correspond to the shape of the slider body periphery 46 adjacent to a particular slider body slot 52. That is, in the exemplary embodiment having an oblong slider body 42, the slider body slots 52 adjacent to the parallel portion of the oblong slider body periphery 46 are generally straight slots 52A. Furthermore, for the reasons discussed above, the slider body groove 52 adjacent the parallel portion of the oblong slider body periphery 46 can be allowed to have greater flexibility relative to the generally arcuate groove 52B discussed below. Conversely, the slider body groove 52 adjacent the arcuate portion of the oblong slider body periphery 46 is a generally arcuate groove 52B. The slider body groove 52 extending over the transition between the parallel portion of the oblong slider body periphery 46 and the arcuate portion of the oblong slider body periphery 46 will have a partially straight and partially arcuate groove 52C.

Furthermore, in the exemplary embodiment, the sliding body grooves 52 are "circumferentially adjacent" to one another. That is, as used herein, "circumferentially adjacent" means that the distance between the grooves 52 is less than the length along the longitudinal centerline 59 of the sliding body grooves. In this configuration, the grooves define sliding body support elements 70 between adjacent grooves 52. In other words, the portion of the sliding body body 42 between the grooves 52 is defined as the sliding body support elements 70. For clarity, the sliding body support elements 70 between the grooves 52 in the first set of sliding body body outer channels 60 are identified as sliding body first supports 72, and the sliding body support elements 70 between the grooves 52 in the second set of sliding body body outer channels 62 are identified as sliding body second supports 74.

The first set of slider body outer channels 60 are positioned "effectively adjacent" to the slider body periphery 46. In this configuration, the first set of slider body outer channels 60 define an outer annulus 80. That is, as used herein, an "annulus" is the material of the body remaining after forming a plurality of adjacent channels. An "annulus" is material disposed between a channel and an adjacent surface, or between concentric groups of channels. Thus, in this configuration, the outer annulus 80 comprises the slider body edge surface 49.

As described above, in this configuration, each slot 52 is configured to allow the slider body edge surface 49 to be flexible. That is, when sufficient bias is applied to the slider body edge surface 49 adjacent the slot 52, the outer band 80 defining that portion of the slider body edge surface 49 deflects into the slot 52. Note that the portion of the outer band 80 adjacent the slot middle portion 56 can bend further than the portion of the outer band 80 adjacent the slot first end 54 or second end 58. Furthermore, the portion of the outer band 80 adjacent the slider support element 70 will only bend a negligible distance.

Accordingly, the second set of sliding body body outer channels 62 are arranged to be effectively adjacent to the first set of sliding body body outer channels 60. That is, the second set of sliding body body outer channels 62 are arranged around the first set of sliding body body outer channels 60 and define an inner annulus 82 therebetween. In addition, the position of the sliding body second support portion 74 deviates from the position of the sliding body first support portion 72. That is, the sliding body first support portion 72 is arranged at the groove middle portion 56 of the groove 52 in the second set of sliding body body outer channels 62. In this configuration, when sufficient bias is applied to the sliding body body edge surface 49 adjacent to the sliding body first support portion 72, the inner annulus 82 adjacent to the sliding body first support portion 72 will bend into the groove 52 adjacent to the sliding body first support portion 72. Therefore, in an embodiment in which the sliding body body outer channels 50 extend around the sliding body body periphery 46, there is no inflexible portion on the sliding body body edge surface 49.

Thus, in the above configuration, the slider body outer channel 50 and the slider body annulus 80, 82 are the flexible component 11. Thus, when the slider body 42 is made of a durable material, the rotor assembly body outer surface 23 is a durable, flexible rotor assembly body outer surface 23. Alternatively, when the slider body 42 is made of a strong material, the rotor assembly body outer surface 23 is a strong, flexible rotor assembly body outer surface 23.

It should be noted that the grooves 52, and in particular the illustrated configuration of the grooves 52, are merely examples. The slider body outer passage 50 can have any shape, including but not limited to a generally circular opening, a generally square opening, a generally diamond-shaped opening, a generally elliptical opening, a generally triangular opening, a generally hexagonal opening, a generally octagonal opening, a partial radial groove, and a spiral groove. Furthermore, a set of outer passages 60, 62 need not have uniform size or shape. In other words, a set of outer passages 60, 62 can include any or all of the aforementioned shapes. For example, in the above configuration, the slider support element 70 can include a circular opening. Furthermore, while the slider body outer passage 50 shown in the figures includes a generally smooth surface, the slider body outer passage 50 can have any shape, including shapes other than smooth surfaces. Furthermore, in an exemplary embodiment not shown, the outer passage 50 includes an internal support member 68. For example, the internal support member 68 can be a generally elongated rod or ring disposed within the outer passage 50. The internal support 68 can be made of the same material as the sliding body main body 42, that is, the outer channel 50 can be formed in a manner in which the internal support 68 is formed when the outer channel 50 is cut out. Alternatively, the internal support 68 can be made of another material and then coupled, directly coupled, or fixed to the sliding body main body 42. In another exemplary embodiment, the internal support 68 is a spring (not shown).

In another embodiment, as shown in FIG3 , the flexible assembly 11 in the plurality of channels 31 is a rotor lamination body 32. That is, the above description regarding the slider body 42 also applies to the rotor lamination body 32. It should be understood that the previous seven paragraphs can be rewritten and generally describe the flexible assembly 11 on the rotor lamination body 32 by changing the term "slider body" to "rotor lamination body." This disclosure is incorporated herein by reference. In the exemplary embodiment, each rotor lamination body 32 is a single body.

In another embodiment (not shown), the flexible assembly 11 including the external channels is incorporated into a unitary rotor assembly body 22. That is, the unitary rotor assembly body 22 includes a plurality of channels (not shown) disposed adjacent to the rotor assembly body outer surface 23. In the exemplary embodiment, the channels are disposed in a configuration similar to that described above, i.e., concentric grooves. In this embodiment, the channels are formed in the unitary rotor assembly body 22 by 3D printing, electro-discharge machining, investment casting, or any other suitable method.

As shown in FIG5 , stator assembly 100 includes a body 102 defining a spiral channel 104. In an exemplary embodiment, stator assembly body 102 is a "stack" of stator laminations 101, i.e., a stack of stator lamination bodies 110. In other exemplary embodiments not shown but discussed below, stator assembly body 102 is formed using conventional methods as described above. In exemplary embodiments where stator assembly body 102 is a stack of stator laminations 101, each stator lamination 101 includes body 110, which, in exemplary embodiments, is a single body. Stator assembly lamination body 110 is constructed as follows.

As previously described, a "laminate body" or "laminate" is a generally planar body having a thickness between approximately 0.010 and 0.100 inches, or approximately 0.025 inches. In the exemplary embodiment, the stator assembly laminate body 110 is made of a durable or strong material. Furthermore, the stator assembly laminate body 110 includes a generally circular outer periphery 112 and defines a primary inner channel 114 and a plurality of outer channels 116. As described below, the stator assembly laminate body inner channel 114 defines the stator assembly spiral channel 104, or "spiral channel 104." As described above, in the exemplary embodiment shown, the spiral channel 104 has one more lobe than the rotor assembly body 22; thus, in the embodiment shown in FIG3 and operable with a single-lobed rotor assembly body 22, the stator assembly laminate body inner channel 114 is an oblong channel. The stator assembly laminate body inner channel 114 has a periphery 117 and defines an inner surface 118, which is a planar body edge surface.

In an exemplary embodiment, the stator assembly laminate body outer channel 116 is disposed "effectively adjacent" to at least a portion of the stator assembly laminate body inner channel perimeter 117 and the stator assembly laminate body inner channel inner surface 118. In an exemplary embodiment, the stator assembly laminate body outer channel 116 extends around the stator assembly laminate body inner channel perimeter 117 and the stator assembly laminate body inner channel inner surface 118. As described below, the stator assembly laminate body outer channel 116 is configured to allow the stator assembly laminate body inner channel inner surface 118 to be flexible.

In the exemplary embodiment, the stator assembly lamination body outer channels 116 are elongated slots 120 arranged in a concentric configuration. That is, there is a first group of stator assembly lamination body outer channels 140 (i.e., a "first group" collectively identified by reference numeral 140) and a second group of stator assembly lamination body outer channels 142 (i.e., a "second group" collectively identified by reference numeral 142). Each stator assembly lamination body outer channel slot 120 is an elongated opening having a first end 124, a middle portion 126, a second end 128, and a longitudinal centerline 129. In the exemplary embodiment, as shown, the dimensions of the stator assembly lamination body outer channel slots 120 (i.e., the length along the stator assembly lamination body slot longitudinal centerline 129) are generally similar. The stator assembly lamination body outer channel slots 120 generally correspond to the shape of the stator assembly lamination body inner channel perimeter 117 adjacent to a particular stator assembly lamination body outer channel slot 120. That is, in the exemplary embodiment having the stator assembly lamination body inner channel 114, the stator assembly lamination body outer channel slots 120 adjacent to the parallel portion of the oblong stator assembly lamination body inner channel perimeter 117 are generally straight slots 120A. Conversely, the stator assembly lamination body outer channel slots 120 adjacent to the arcuate portion of the oblong stator assembly lamination body inner channel perimeter 117 are generally arcuate slots 120B. The stator assembly lamination body outer channel slots 120 extending over the transition portion between the parallel portion of the oblong stator assembly lamination body inner channel perimeter 117 and the arcuate portion of the oblong stator assembly lamination body inner channel perimeter 117 will have partially straight and partially arcuate slots 120C.

Furthermore, in the exemplary embodiment, the stator assembly laminate body outer channel slots 120 are "circumferentially adjacent" to one another. In this configuration, the stator assembly laminate body slots 120 define stator assembly laminate body support elements 160 between adjacent stator assembly laminate body slots 120. In other words, the portion of the stator assembly laminate body 110 between the stator assembly laminate body outer channel slots 120 is defined as the stator assembly laminate body support elements 160. For clarity, the stator assembly laminate body support elements 160 between the stator assembly laminate body outer channel slots 120 in the first set of stator assembly laminate body outer channels 140 are identified as stator assembly laminate body first support portions 162, and the stator assembly laminate body support elements 160 between the stator assembly laminate body outer channel slots 120 in the second set of stator assembly laminate body outer channels 142 are identified as stator assembly laminate body second support portions 164.

The first set of stator assembly lamination body outer channels 140 are positioned "effectively adjacent" to the stator assembly lamination body inner channel perimeter 117. In this configuration, the first set of stator assembly lamination body outer channels 140 define a stator assembly lamination body inner band 180. Thus, in this configuration, the stator assembly lamination body inner band 180 comprises the stator assembly lamination body inner channel inner surface 118.

As described above, in this configuration, each stator assembly lamination body slot 120 is configured to allow the stator assembly lamination body inner channel inner surface 118 to be flexible. That is, when a sufficient bias is applied to the stator assembly lamination body inner channel inner surface 118 adjacent to the stator assembly lamination body outer channel slot 120, the stator assembly lamination body inner band 180 defining that portion of the stator assembly lamination body inner channel inner surface 118 deflects into the stator assembly lamination body outer channel slot 120. Note that the portion of the stator assembly lamination body inner band 180 adjacent to the slot mid-portion 56 can flex further than the portion of the stator assembly lamination body inner band 180 adjacent to the slot first end 124 or second end 128. Furthermore, the portion of the stator assembly lamination body inner band 180 adjacent to the slider support element 70 will flex only a negligible distance.

Accordingly, the second set of stator assembly lamination body outer channels 142 is positioned effectively adjacent to the first set of stator assembly lamination body outer channels 140. That is, the second set of stator assembly lamination body outer channels 142 is positioned around the first set of stator assembly lamination body outer channels 140 and defines an outer annular band 182 therebetween. Furthermore, the position of the stator assembly lamination body second support portion 164 is offset from the position of the stator assembly lamination body first support portion 162. That is, the stator assembly lamination body first support portion 162 is positioned at the slot mid-portion 126 of the stator assembly lamination body outer channel slot 120 in the second set of stator assembly lamination body outer channels 142. In this configuration, when a sufficient bias is applied to the stator assembly lamination body inner channel inner surface 118 adjacent to the stator assembly lamination body first support portion 162, the outer band 182 adjacent to the stator assembly lamination body first support portion 162 will bend into the stator assembly lamination body outer channel slot 120 adjacent to the stator assembly lamination body first support portion 162. Thus, in embodiments where the stator assembly lamination body outer channel 116 extends around the stator assembly lamination body inner channel periphery 117, no inflexible portion of the stator assembly lamination body inner channel inner surface 118 exists. Thus, in the above configuration, the stator assembly lamination body outer channel 116 and the stator assembly lamination body bands 180, 182 comprise the flexible component 11. In other words, the spiral channel 104 comprises the flexible component 11. Thus, when the stator lamination body 110 is made of a durable material, the stator assembly spiral channel surface 105 is a durable, flexible stator assembly spiral channel surface 105, and the stator assembly lamination body inner channel 114 is a durable, flexible stator assembly lamination body inner channel 114. Alternatively, when the stator lamination body 110 is made of a strong material, the stator assembly spiral channel surface 105 is a strong, flexible stator assembly spiral channel surface 105, and the stator assembly lamination body inner channel 114 is a strong, flexible stator assembly lamination body inner channel 114.

It should be noted that the stator assembly lamination body outer channel slots 120, and in particular the illustrated configuration of the stator assembly lamination body outer channel slots 120, are merely examples. The stator assembly lamination body outer channel slots 116 can have any shape, including, but not limited to, generally circular openings, generally square openings, generally diamond-shaped openings, generally elliptical openings, generally triangular openings, generally hexagonal openings, generally octagonal openings, partial radial slots, and spiral slots. Furthermore, a set of outer channels need not have uniform size or shape. That is, a set of outer channels can include any or all of the shapes described above. For example, in the above configuration, the stator assembly lamination body support element 160 can include circular openings. Furthermore, while the stator assembly lamination body outer channel 116 is illustrated as including a generally smooth surface, the stator assembly lamination body outer channel 116 can have any shape, including shapes other than smooth surfaces. As described above, the stator assembly lamination body outer channel 116 can also include internal supports (not shown).

In another embodiment (not shown), the flexible assembly 11 including the outer channels is incorporated into a monolithic stator assembly body (not shown). That is, the monolithic stator assembly body includes a plurality of channels (not shown) disposed adjacent to the main inner channels (not shown) of the stator assembly. In an exemplary embodiment, the channels are arranged in a configuration similar to that described above, i.e., concentric slots. In this embodiment, the channels are formed in the monolithic stator assembly body by 3D printing, electro-discharge machining, investment casting, or any other suitable method.

The stator assembly lamination bodies 110 are assembled into the stator assembly body 102. Typically, the stator assembly lamination bodies 110 are assembled into a stacked body and coupled as described above. However, to form the spiral channel 104, as shown in FIG6 , each stator assembly lamination body 110 is angularly offset, i.e., slightly rotated relative to the adjacent stator assembly lamination bodies 110. That is, each stator assembly lamination body 110 includes a first reference location 200; as shown, the stator assembly lamination body first reference location 200 is located along the longitudinal axis 202 of the channel 114 within the stator assembly lamination body. Thus, if the first stator assembly lamination body 110′ is oriented with the stator assembly lamination body first reference position 200′ in a vertical position, the second stator assembly lamination body 110″ is oriented with the stator assembly lamination body first reference position 200′ at a position radially offset from the vertical position. Similarly, the third stator assembly lamination body 110′″ is oriented with the stator assembly lamination body first reference position 200′ at a position radially offset from the second stator assembly lamination body first reference position 200″. It should be understood that the radial offset between the stator assembly lamination bodies 110 is substantially uniform. By way of example, if the spiral channel 104 extends over an arc of over ninety degrees and the stator assembly body 102 is made of ninety stator assembly lamination bodies 110, then each stator assembly lamination body 110 will be radially offset from each adjacent stator assembly lamination body 110 by approximately one degree.

In addition, in this configuration, the stator assembly lamination body outer channel 116 also forms an elongated spiral channel, hereinafter referred to as the "outer spiral channel" 190. In an exemplary embodiment, the outer spiral channel 190 is filled with an elastomeric material, not shown. In this embodiment, the elastomeric material adheres to the stator assembly lamination body 110. Therefore, if a portion of the stator assembly lamination body inner annulus 180 detaches from the stator assembly lamination body 110 during operation of the progressive cavity pump 10, the elastomeric material can prevent debris from moving through the stator assembly 100. In another alternative embodiment, a plurality of stator assembly lamination bodies 110 at the upstream and downstream ends of the stack are filled with an elastomeric material (not shown), while the remaining stator assembly lamination bodies are filled with a dye (not shown) or a similar material. In this configuration, the outer spiral channel 190 is sealed by the elastomeric material at the upstream and downstream ends. Furthermore, if a portion of the stator assembly lamination body inner band 180 becomes detached from the stator assembly lamination body 110, the dye will escape and mix with the material being moved (or the drive fluid) and may be detected by a sensor (not shown) at a downstream location or by a user. Thus, the dye and sensor (if used) act as a damage warning system.

In the exemplary embodiment, the monolithic rotor assembly body 22 is disposed within the spiral channel 104 and seals against the spiral channel 104 along at least one sealing line. That is, at least one location along the periphery of the monolithic rotor assembly body 22 substantially contacts the spiral channel 104. This relationship can be visualized at a cross-sectional plane of the monolithic rotor assembly body 22 and the spiral channel 104. Furthermore, this visualization conveniently corresponds to the interaction between the monolithic rotor assembly body 22 and the stator lamination body 110. As described above, in the exemplary embodiment, the rotor assembly body 22 substantially seals against the arcuate portion of the spiral channel 104. The rotor assembly body 22 is generally sealed against the linear portion of the spiral channel 104, but the sealing in this area is less critical than the sealing in the arcuate portion of the spiral channel 104.

Thus, in the illustrated embodiment, the monolithic rotor assembly body 22 has a substantially circular cross-sectional area. In one exemplary embodiment, the diameter of the monolithic rotor assembly body 22 is substantially the same as the distance between the parallel sides of the oblong spiral channel 104. In this configuration, the diameter of the monolithic rotor assembly body 22 substantially corresponds to the lateral width of the oblong spiral channel 104 (i.e., the width between the two substantially parallel sides of the oblong shape). In addition, the curvature of the monolithic rotor assembly body 22 substantially corresponds to the arcuate portion of the oblong spiral channel 104. Thus, the monolithic rotor assembly body 22 substantially engages the oblong spiral channel 104 at two opposing locations when positioned in the middle portion of the oblong spiral channel 104, and substantially engages the arcuate portion of the oblong spiral channel 104 when positioned at either end of the oblong spiral channel 104. As shown, when the monolithic rotor assembly body 22 rotates, the monolithic rotor assembly body 22 at a particular transverse plane reciprocates within the oblong spiral channel 104. Thus, in essence, the oblong spiral channel 104 is divided into two cavities; one on either side of the unitary rotor assembly body 22. It will be appreciated that the unitary rotor assembly body 22 engages substantially one arcuate portion of the oblong spiral channel 104 when the unitary rotor assembly body 22 reaches maximum lateral deflection.

In another embodiment, the oblong spiral channel 104, or in other words, each oblong stator assembly lamination body inner channel 114, is slightly smaller than the cross-sectional area of the monolithic rotor assembly body 22. This is possible due to the flexible component 11 on the stator assembly lamination body 110. That is, the inner surface 118 of each stator assembly lamination body inner channel closely corresponds to the monolithic rotor assembly body 22. In this configuration, and when the monolithic rotor assembly body 22 reciprocates as described above, the flexible component 11 on the stator assembly lamination body 110 allows each stator assembly lamination body inner channel 114 to expand (i.e., bend) to a slightly larger cross-sectional area sufficient to accommodate the monolithic rotor assembly body 22.

In the above-described embodiment, the monolithic rotor assembly body 22 engages and seals against the spiral channel 104 along at least one sealing line. Almost literally, a sealing line is a line, i.e., a very thin, nearly linear interface. It should be understood that in the physical world, no interface exists directly along a two-dimensional line. If, for example, there were a scratch on the stator assembly spiral channel surface 105, the sealing line would not be able to engage the scratched surface and, therefore, would not seal the cavity as described above. In embodiments in which the rotor assembly 20 includes a rotor assembly stack body 30, the edge surfaces of the rotor lamination bodies 32 extend in a direction generally parallel to the axis of rotation of the rotor assembly 20. Similarly, each stator assembly lamination body inner channel inner surface 118 extends in a direction generally parallel to the axis of rotation of the rotor assembly 20. In embodiments having a rotor assembly stack body 30, each rotor lamination body 32 is disposed within a single stator assembly lamination body inner channel 114, i.e., within the plane of a single stator assembly lamination body 110. Thus, each rotor lamination body 32 is associated with the stator assembly lamination body 110 in which it is disposed. As described above, the thickness of each rotor lamination body 32 is substantially the same as the thickness of the associated stator lamination body 110. In this configuration, the adjoining edge surfaces of the rotor lamination bodies 32 and the inner channel inner surfaces 118 of the stator assembly lamination bodies provide a more complete seal than the seal line of the above-described embodiment. That is, as used herein, a "more complete seal" is a planar seal area as opposed to a seal line.

Thus, as described above, in the above configuration, the progressive cavity pump 10 includes a durable, flexible stator assembly spiral channel surface 105. That is, the progressive cavity pump 10 is configured to provide a flexible surface on at least one of the engaging surfaces of the rotor assembly body 22 or the stator assembly spiral channel 104.

In another embodiment, the rotor assembly 20 includes a plurality of sliders 40 as described above. That is, the rotor assembly 20 includes a unitary rotor assembly body 22 as described above, except that the unitary rotor assembly body 22 is sized to fit within the rotor body channel 44 and is not sized to correspond to the width of the oblong spiral channel 104. As with the rotor lamination bodies 32, each slider body 42 is associated with a single stator assembly lamination body 110 and is disposed within a single stator assembly lamination body inner channel 114, i.e., within the plane of the single stator assembly lamination body 110. Each slider body 42 is further disposed on the unitary rotor assembly body 22. That is, as shown in FIG4 , for each slider body 42, the unitary rotor assembly body 22 is disposed within the rotor body channel 44, and each slider body 42 is movably disposed within the associated stator assembly lamination body inner channel 114. In this configuration, as the monolithic rotor assembly body 22 rotates, the monolithic rotor assembly body 22 operably engages the rotor body channel raised surfaces 45 , thereby causing the slider body 42 to reciprocate within the associated stator assembly lamination body inner channel 114 .

Therefore, in the above-described configuration, the progressive cavity pump 10 includes a durable, flexible rotor assembly outer surface 23. That is, the progressive cavity pump 10 is configured to provide a flexible surface on at least one of the engaging surfaces of the rotor assembly body 22 or the stator assembly spiral channel 104. Furthermore, as shown in FIG4 , the stator assembly spiral channel surface 105 also includes a flexible component 11. Therefore, both the rotor assembly outer surface 23 and the stator assembly spiral channel surface 105 include a flexible component 11. In other words, the interface 300 between the rotor assembly outer surface 23 and the stator assembly spiral channel surface 105 is a flexible interface. That is, as used herein, a "flexible interface" is an interface in which both elements forming the interface have a flexible construction. Furthermore, when both elements forming the interface are made of durable materials, the interface 300 is a durable, flexible interface 300. Alternatively, if both elements forming the interface are made of robust materials, the interface 300 is a robust, flexible interface 300.

It is noted that in this construction, the angularly offset stator lamination bodies 110 form a series of steps or layers within the stator assembly spiral channel 104. These steps affect the flow of material through the stator assembly spiral channel 104; that is, the steps create turbulence in the material flow. Therefore, the steps act as turbulators 170. In addition, the turbulators 170 are not machined into the stator lamination bodies 110 or formed by another manufacturing process. Therefore, the turbulators 170 are "intrinsic turbulators" 170. That is, as used herein, "intrinsic turbulators" are turbulators formed by a lamination body or a similarly constructed assembly, rather than by cutting or otherwise forming grooves or channels in the body. It is noted that the rotor assembly stacked body 30 described above also forms inherent turbulators.

Accordingly, the method of manufacturing the rotor assembly 20 includes the following steps. A plurality of rotor lamination bodies 32 are provided, each rotor lamination body 32 including the flexible assembly 11, and the rotor lamination bodies 32 are assembled into a stack. Providing the plurality of rotor lamination bodies 32 includes providing lamination material, forming the rotor lamination bodies 32, the rotor lamination bodies having a plurality of outer channels, the plurality of outer channels being arranged operatively adjacent to the rotor lamination body edges 34. Providing the lamination material, forming the rotor lamination bodies 32 includes cutting the rotor lamination bodies 32 from the lamination material, and cutting the plurality of outer channels, the plurality of outer channels being arranged operatively adjacent to the rotor lamination body edges 34. In an exemplary embodiment, cutting the plurality of outer channels includes cutting a first set (not shown) of outer channels, the first set of outer channels being arranged operatively adjacent to the rotor lamination body edges 34, and cutting a second set (not shown) of outer channels, the second set of outer channels being arranged operatively adjacent to the first set of outer channels. Assembling the rotor lamination bodies 32 includes coupling the rotor lamination bodies 32 and at least one of: riveting the rotor lamination bodies 32 , welding outer surfaces of the rotor lamination bodies 32 , welding each rotor lamination body 32 to adjacent rotor lamination bodies 32 , or mechanically compressing the rotor lamination bodies 32 .

In an alternative embodiment, providing a plurality of rotor lamination bodies 32 includes providing lamination material, forming the rotor lamination bodies 32, and forming a slider body 42 having a plurality of outer channels and rotor body channels 44, the plurality of outer channels being disposed operatively adjacent to the slider body edge surface 49. Forming the rotor lamination bodies 32 from the lamination material includes cutting the rotor lamination bodies 32 from the lamination material. Forming the slider body 42 includes cutting the slider body 42 from the lamination material, cutting the plurality of outer channels 50 disposed operatively adjacent to the slider body edge surface 48, and cutting the rotor body channels 44. In an exemplary embodiment, cutting the plurality of outer channels includes cutting a first set 60 of outer channels disposed operatively adjacent to the slider body edge surface 49, and cutting a second set 62 of outer channels disposed operatively adjacent to the first set 60 of outer channels 62. In this embodiment, assembling the rotor lamination bodies 32 includes riveting the rotor lamination bodies 32, welding the outer surfaces of the rotor lamination bodies 32, welding each rotor lamination body 32 to an adjacent rotor lamination body 32, or mechanically compressing the rotor lamination bodies 32. In this embodiment, there is also the step of placing the slider body 42 on the associated rotor lamination body 32.

Similarly, the method of manufacturing the stator assembly 100 includes the following steps. A plurality of stator lamination bodies 102 are provided, each stator lamination body 102 including the flexible assembly 11, and the stator lamination bodies 102 are assembled into a stack. Providing the plurality of stator lamination bodies 102 includes providing lamination material, forming a stator lamination body 110 having an inner channel 114 and a plurality of outer channels 116 disposed operatively adjacent to the stator inner channel 114. Providing the lamination material, forming the rotor lamination body 32 includes cutting the stator lamination body 110 from the lamination material, cutting the inner channel 114, and cutting the plurality of outer channels 116 disposed operatively adjacent to the stator inner channel 114. In an exemplary embodiment, cutting the plurality of outer channels 116 includes cutting a first group 140 of outer channels disposed operatively adjacent to the stator inner channel 114, and cutting a second group 142 of outer channels 116 disposed operatively adjacent to the first group 140 of outer channels 116. Assembling the stator lamination bodies 110 includes coupling the stator lamination bodies 110, wherein each stator lamination body 110 is angularly offset from an adjacent stator lamination body 110. Coupling the stator lamination bodies 110 includes at least one of riveting the stator lamination bodies 110, welding 1164 the outer surfaces of the stator lamination bodies 110, welding each stator lamination body 110 to an adjacent stator lamination body 110, or mechanically compressing the stator lamination bodies 110. As described above, this method forms the inner channel 114 at least partially defined by the annulus 180, wherein the annulus 180 is flexible.

While specific embodiments of the present disclosure have been described in detail, those skilled in the art will appreciate that various modifications and alternatives to those details could be developed in light of the overall teachings of the present disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the claims appended and any and all equivalents thereof.

Claims (17)

1. A stator lamination (101) for a progressive cavity pump stator assembly (1), comprising: The planar body (102) of the single unit defines a main inner channel (114) and a plurality of outer channels (116); The outer channel (116) is configured to effectively proximate the inner channel (114), whereby the inner channel (114) is at least partially defined by the annular band (180); and The ring band (180) and the outer channel (116) constitute a flexible component (11). 2. The stator lamination (101) as claimed in claim 1, wherein the plurality of outer channels (116) includes circumferentially adjacent channels (116). 3. The stator lamination (101) as described in claim 2, wherein: The plurality of external channels (116) include a plurality of slots (120); Each groove (120) includes a first end (124), a middle portion (126), and a second end (128); and The slot (120) defines a plurality of support elements (160) between adjacent slots (120). 4. The stator lamination (101) as claimed in claim 3, wherein the plurality of outer channels (116) are arranged around the inner channel (114). 5. The stator lamination (101) as described in claim 4, wherein: The plurality of external channels (116) includes a first group of external channels (140) and a second group of external channels (142); The first set of outer channels (140) are arranged around the inner channel (114); The first set of outer channels (140) defines a plurality of first support elements (162) between adjacent channels; The second set of outer channels (142) is arranged around the first set of outer channels (140); the second set of outer channels (142) defines a plurality of second support elements (164) between adjacent channels. 6. The stator lamination (101) as described in claim 5, wherein: The longitudinal axis (202) of each radially first support element (162) is positioned along the middle portion (126) of the channel in the second set of outer channels (142); and The longitudinal axis (202) of each radial second support element (164) is set along the middle portion (126) of the channel in the first set of outer channels (60). 7. The stator lamination (101) as described in claim 1, wherein: The plurality of external channels (116) includes a first group of external channels (140) and a second group of external channels (142); The first set of outer channels (140) is arranged around the inner channel (114); and The second set of outer channels (142) is arranged around the first set of outer channels (140). 8. The stator lamination (101) as claimed in claim 1, wherein the body (102) is made of a durable material. 9. A method of manufacturing a stator assembly (3) for a progressive cavity pump (1), comprising: A plurality of individual stator lamination bodies (110) are provided, each stator lamination body (110) being planar and defining a main inner channel (114) and a plurality of outer channels (116), the outer channels (116) being configured to effectively proximate the inner channel (114), whereby the inner channel (114) is at least partially defined by an annular band (180), wherein the annular band (180) is flexible; and The stator lamination bodies (110) are coupled to each other in a stacked manner, wherein each stator lamination body (110) is offset at an angle from each adjacent stator lamination body. 10. The method of claim 9, wherein providing a plurality of stator lamination bodies (110) comprises: Provide laminated materials; Cut the stator lamination body from the lamination material; Cut an inner channel (114) in the stator lamination body (110); and Multiple outer channels (116) are cut, the multiple outer channels being arranged to be effectively adjacent to the inner channel (114) in the stator lamination body (110). 11. The method of claim 10, wherein cutting the plurality of outer channels (116) comprises: Cut the first set of outer channels (140), the first set of outer channels being configured to effectively proximate the inner channel (114); and Cut the second set of outer channels (142), which are configured to be effectively adjacent to the first set of outer channels (140). 12. The method of claim 9, wherein coupling the stator lamination bodies (110) to each other in a stacked manner includes at least one of stacking the stator lamination bodies (110), welding the outer surfaces of the stator lamination bodies (110), welding each of the stator lamination bodies (110) to an adjacent stator lamination body, or mechanically compressing the stack of the stator lamination bodies (110). 13. A stator assembly (3) for a progressive cavity pump (1), the progressive cavity pump (1) including an elongated helical rotor (2), the stator assembly (3) comprising: Multiple individual stator lamination bodies (110), each stator lamination body (110) is planar, defining a main inner channel (114) and multiple outer channels (116), the outer channels (116) being configured to effectively proximate the inner channel (114), whereby the inner channel (114) is at least partially defined by an annular band (180), wherein the annular band (180) is flexible; The stator lamination bodies (110) are coupled to each other in a stacked manner, wherein the inner channel (114) of the stator lamination body defines a helical channel (104), and the outer channel (116) of the stator lamination body defines a helical outer channel (190); and The spiral channel (104) includes a flexible component (11). 14. The stator assembly (3) of claim 13, wherein the plurality of stator lamination bodies (110) are made of a durable material. 15. The stator assembly (3) of claim 13, wherein the helical rotor (2) includes a body (22) having an outer surface (23) comprising two opposing surfaces, and wherein the helical channel (104) defines either a constant contact channel or a compression channel. 16. The stator assembly (3) of claim 13, wherein the helical channel (104) includes an inherent turbulence generator (170). 17. The stator assembly (3) as claimed in claim 13, wherein: The plurality of external channels (116) of each stator lamination body (110) include a first set of external channels (140) and a second set of external channels (142); The first set of outer channels (140) is arranged around the associated inner channel (114); and The second set of outer channels (142) is arranged around the associated first set of outer channels (140).