Seal assembly and method of using the same

A seal assembly including: a collar having an opening configured to receive a rotatable shaft, an annular member having an annular opening configured to receive the collar, and first and second end plates fixedly coupled to a respective one of the first and second end surfaces of the collar. An outer surface of the collar includes one or more helical threads. The collar has a first axial length defined between first and second end surfaces of the collar, and the annular member has a second axial length defined between first and second end surfaces of the annular member, in which the second axial length is less than the first axial length. Also provided are an assembly comprising a seal assembly in accordance with the present disclosure and a method for preventing contamination of a sealed chamber.

FIELD OF THE INVENTION

This invention relates generally to a seal assembly. More particularly, the invention relates to a seal assembly for use with a rotatable shaft.

BACKGROUND OF THE INVENTION

Seals may be used in various applications to seal a fluid in a bearing housing or machine frame, seal the bearing housing or machine frame against entry of contaminants, and/or remove contaminants from the bearing housing or machine frame. Sealing of a rotating shaft in a housing is an ongoing challenge, particularly in high contamination environments. To address this challenge, different strategies have been employed in the past. One strategy involves the creation of a contact seal between the seal assembly and the surface of the shaft. To create the tight fit necessary to exclude the entry of contamination, these seal assemblies typically utilize either a flexible member that contacts the shaft or magnets mounted to the shaft and the housing. Another strategy involves use of a labyrinth seal, in which a stationary piece is used with a rotating piece that, when assembled together, create an indirect path into the housing. A further strategy includes use of a pressurized barrier or flushing fluid that is forced through a seal structure to flush out and/or exclude contaminants.

These designs each suffer from a number of drawbacks. Contact seal designs depend on a close fit between the seal assembly and the shaft, which causes wear to both components, and any gaps can allow contaminants to enter, which is a particular problem for applications with high shaft deflection due to a long flexible shaft. Labyrinth seals can be overwhelmed by heavy contamination streams. Systems that rely on a barrier/flushing fluid typically require a constant supply of fluid. In configurations where the seal is utilized to contain a process fluid within the housing, the barrier/flushing fluid should be selected for compatibility with the process fluid, as the barrier/flushing fluid may be mixed with the process fluid.

SUMMARY OF THE INVENTION

In accordance with an aspect of the present disclosure, a seal assembly is provided. The seal assembly may comprise: a collar comprising an opening configured to receive a rotatable shaft, an annular member comprising an annular opening configured to receive the collar, and first and second end plates fixedly coupled to a respective one of the first and second end surfaces of the collar. The collar may comprise a first axial length defined between first and second end surfaces of the collar, and an outer surface of the collar may comprise one or more helical threads. The annular member may comprise a second axial length defined between first and second end surfaces of the annular member, in which the second axial length may be less than the first axial length.

The first and second end surfaces of the annular member may be spaced apart from an inner face of the respective first and second end plates.

The first end plate may comprise a first outer diameter and the second end plate may comprise a second outer diameter that is less than the first outer diameter. An outer diameter of the annular member may be substantially the same as the second outer diameter of the second end plate.

The one or more helical threads may comprise two or more threads defining a multi-start thread.

Each of the one or more helical threads may extend around the outer surface of the collar between the first and second end surfaces of the collar.

The first and second end plates may each comprise a plurality of apertures and the respective first and second end surfaces of the collar may each comprise a corresponding plurality of threaded bores. The first and second end plates may be fixedly coupled to the respective first and second end surfaces of the collar by a plurality of fasteners that extend through the apertures and are received in the threaded bores.

In accordance with another aspect of the present disclosure, an assembly is provided that comprises: a housing comprising a housing opening, a seal assembly received in the housing opening, and an annular member. The seal assembly may comprise: a collar comprising an opening configured to receive a rotatable shaft and first and second end plates fixedly coupled to respective first and second end surfaces of the collar. The collar may be configured to be fixedly coupled to the rotatable shaft such that the collar rotates with the rotatable shaft and axial movement of the collar relative to the rotatable shaft is prevented. An outer surface of the collar may comprise one or more helical threads. The annular member may comprise an annular opening configured to receive the collar. The annular member may be coupled to the housing such that rotational and axial movement of the annular member relative to the rotatable shaft is prevented. The one or more helical threads of the collar may be configured such that when the rotatable shaft rotates, an interaction between the outer surface of the collar and an inner surface of the annular opening creates a rotary pump comprising a first axial flow direction extending from inside the housing to outside the housing.

The annular member may further comprise: a first end surface that is spaced apart from an inner face of the first end plate to define an outlet, and a second end surface that is spaced apart from an inner face of the second end plate to define an inlet, in which when the rotatable shaft rotates, the first axial flow direction extends from the inlet toward the outlet and material is prevented from entering the housing through the outlet.

In some examples, the annular member may comprise a discrete ring. The removable ring may comprise a locator pin extending outwardly from an outer surface of the removable ring substantially perpendicular to an axis of rotation of the rotatable shaft, and the housing may comprise a notch configured to receive the locator pin to prevent the rotational movement of the removable ring relative to the rotatable shaft.

In other examples, a portion of the housing may define the annular member.

The first end plate may comprise a first outer diameter and the second end plate may comprise a second outer diameter that is less than the first outer diameter. The first outer diameter may be greater than a diameter of the housing opening.

The housing opening may comprise a first housing opening, and the seal assembly may comprise a first seal assembly. The assembly may further comprise: a second seal assembly received in a second housing opening opposite the first housing opening and a second annular member. The second seal assembly may comprise: a second collar comprising a second opening configured to receive the rotatable shaft and third and fourth end plates fixedly coupled to respective third and fourth end surfaces of the second collar. The second collar may be configured to be fixedly coupled to the rotatable shaft such that the second collar rotates with the rotatable shaft and axial movement of the second collar relative to the rotatable shaft is prevented. A second outer surface of the second collar may comprise one or more second helical threads. The second annular member may comprise a second annular opening configured to receive the second collar. The second annular member may be coupled to the housing such that rotational and axial movement of the second annular member relative to the rotatable shaft is prevented. The one or more second helical threads of the second collar may be configured such that when the rotatable shaft rotates, an interaction between the second outer surface of the second collar and an inner surface of the second annular opening creates a second rotary pump comprising a second axial flow direction extending from inside the housing to outside the housing. The second axial direction may be opposite the first axial direction.

The opening of the collar of the first seal assembly may comprise a first inner diameter, and the second opening of the second collar may comprise a second inner diameter that is different from the first inner diameter.

The one or more helical threads of the collar of the first seal assembly may comprise one of a right-handed thread or left-handed thread, and the one or more second helical threads of the second collar may comprise the other of the right-handed thread or the left-handed thread.

The second annular member may further comprise: a third end surface that is spaced apart from an inner face of the third end plate to define a second outlet, and a fourth end surface that is spaced apart from an inner face of the fourth end plate to define a second inlet, in which when the rotatable shaft rotates, the second axial flow direction extends from the second inlet toward the second outlet and the material is prevented from entering the housing through the second outlet.

In accordance with a further aspect of the present disclosure, a method for preventing contamination of a sealed chamber is provided. The method may comprise: fixedly coupling an annular rotor member to a rotatable shaft such that axial movement of the annular rotor member relative to the rotatable shaft is prevented, in which an outer surface of the annular rotor member may comprise one or more helical threads; providing an annular stator member that may be fixedly coupled to a housing such that rotational and axial movement of the annular stator member relative to the rotatable shaft is prevented; inserting the rotatable shaft into the housing such that the outer surface of the annular rotor member is adjacent to an inner surface of the annular stator member to generate the sealed chamber; and rotating the rotatable shaft. The one or more helical threads may be configured such that an interaction between the outer surface of the annular rotor member and the inner surface of the annular stator member generates a rotary pump comprising a first axial flow direction extending from inside the housing to outside the housing and prevents material from entering the sealed chamber.

The method may further comprise: fixedly coupling a second annular rotor member to the rotatable shaft such that axial movement of the second annular rotor member relative to the rotatable shaft is prevented, in which an outer surface of the second annular rotor member may comprise one or more second helical threads; and providing a second annular stator member that is fixedly coupled to the housing such that rotational and axial movement of the second annular stator member relative to the rotatable shaft is prevented. When the rotatable shaft is inserted into the housing, the outer surface of the second annular rotor member may be adjacent to an inner surface of the second annular stator member to generate the sealed chamber. The one or more second helical threads may be configured such that, when the rotatable shaft is rotated, an interaction between the outer surface of the second annular rotor member and the inner surface of the second annular stator member generates a second rotary pump that comprises a second axial flow direction extending from inside the housing to outside the housing and prevents the material from entering the sealed chamber. The second axial flow direction may be opposite the first axial flow direction.

DETAILED DESCRIPTION OF THE INVENTION

The present description is directed to seal assemblies and methods for use thereof to control and prevent contaminant ingression into a bearing housing or machine frame. A seal assembly in accordance with the present disclosure works to actively expel contaminants that may be attempting to enter the housing from outside and further expel contaminants within the housing that may be entering the seal assembly. The seal assembly is coupled to a rotatable shaft and utilizes energy from the rotation of the shaft to create a rotary pump causing materials such as contaminants, fluids, etc. to move in an axial flow direction extending from inside the housing to outside the housing, thereby excluding and/or expelling contamination. Seal assemblies in accordance with the present disclosure may be particularly useful in high contamination environments, such as paper mills.

With reference toFIGS. 1-4 and 6, a seal assembly10is shown, in which the seal assembly10may be used to seal a rotatable shaft100in a housing104. Spacing between the components of the seal assembly10inFIG. 4is exaggerated to illustrate aspects of the structure in detail. The seal assembly10may comprise a collar12, an annular member14, a first end plate16, and a second end plate18. The collar12(also referred to herein as a first annular rotor member) comprises first and second end surfaces12-1and12-2, an outer circumferential surface12-3, and an inner surface12-4. The inner surface12-4of the collar12defines an opening20that receives the shaft100, as described herein. The outer surface12-3defines an outer diameter OD12of the collar12, and the inner surface12-4defines an inner diameter ID12of the collar12, in which the inner diameter ID12of the collar12defines a diameter (not separately labeled) of the opening20. With reference toFIGS. 2 and 4, the collar12may comprise an axial length L12defined between the first and second end surfaces12-1and12-2, in which the axial length L12is measured in a direction substantially parallel to an axis of rotation A11of the collar12. The collar12may be substantially cylindrical, with the inner and outer diameters ID12and OD12being substantially the same along an entirety of the axial length L12of the collar12.

The annular member14(also referred to herein as a first annular stator member) may comprise a separate or discrete ring, as shown inFIGS. 1 and 4, or may be defined by a portion of the housing104, as described herein in more detail with respect toFIG. 11. With reference toFIGS. 1 and 4, the annular member14comprises first and second end surfaces14-1and14-2, an outer surface14-3, and an inner surface14-4. The inner surface14-4of the annular member14defines an annular opening22that receives the collar12, as described herein. The outer surface14-3of the annular member14defines an outer diameter OD14of the annular member14, and the inner surface14-4defines an inner diameter ID14of the annular member14, in which the inner diameter BMA of the annular member14defines a diameter (not separately labeled) of the annular opening22. As shown inFIG. 4, the annular member14may comprise an axial length L14defined between first and second end surfaces14-1and14-2of the annular member14, in which the axial length L14is measured in a direction substantially parallel to an axis of rotation A12of the collar12. The annular member14may be substantially cylindrical, with the inner and outer diameters ID14and OD14being substantially the same along an entirety of the axial length L14of the annular member14.

The annular opening22of the annular member14may be configured to receive the collar12. In some examples, the inner diameter ID14of the annular member14may be slightly greater than the outer diameter OD12of the collar12, as best seen inFIG. 4. In some particular examples, the inner diameter ID14of the annular member14may be about 4.260 inches, and the outer diameter OD12of the collar12may be about 4.250 inches. This small amount of clearance between the inner surface14-4of the annular member14and the outer surface12-3of the collar12helps to prevent or minimize contact between the collar12and the annular member14and allows the collar12to rotate freely with respect to the annular member14, as described herein in detail. The axial length L14of the annular member14may be less than the axial length L12of the collar12, as shown inFIG. 4. In some particular examples, the axial length L14of the annular member14may be 0.9375 inches, and the axial length L12of the collar12may be 1.000 inches.

The first and second end plates16and18may be fixedly coupled to the collar12. For example, with reference toFIGS. 1, 2, and 4, the first end plate16may comprise a plurality of apertures16A formed through a thickness T16of the first end plate16, and the first end surface12-1of the collar12may comprise a corresponding plurality of threaded bores12A. Fasteners24may extend through the apertures16A formed in the first end plate16and may be received in the threaded bores12A formed in the first end surface12-1of the collar12to secure the first end plate16to the first end surface12-1of the collar12. With reference toFIGS. 2-4, the second end plate18may comprise a plurality of apertures (not visible) formed through a thickness T18of the second end plate18, and the second end surface12-2of the collar12may comprise a corresponding plurality of threaded bores12B. The second end plate18may be similarly secured to the second end surface12-2of the collar12by inserting fasteners25through the apertures formed in the second end plate18and into the threaded bores12B formed in the second end surface12-2of the collar12. The fasteners24and25may comprise screws, bolts, or any other suitable type of fastener.

The collar12, the annular member14, and the end plates16and18may be made from any suitable material and may comprise, for example, a metal or metal alloy (e.g., bronze, steel, aluminum, etc.) or an engineering plastic or other hard plastic such as polyamides (e.g., nylon), polyimides, polycarbonates, etc. In one particular example, the collar12may comprise bronze, the annular member14may comprise nylon, and the end plates16and18may comprise aluminum.

As shown inFIG. 4, because the axial length L14of the annular member14is less than the axial length Lie of the collar12, the first end surface14-1of the annular member14may be spaced apart from an inner face16-1of the first end plate16by a first distance D1, and the second end surface14-2of the annular member14may be spaced apart from an inner face18-1of the second end plate18by a second distance D2, when the first and second end plates16and18are coupled to the collar12(see alsoFIG. 8A). In some examples, the first and second distances D1and D2may be substantially the same.

With continued reference toFIG. 4, the first end plate16may comprise a first outer diameter OD16. In some examples, the second end plate18may comprise a second outer diameter OD18that is less than the first outer diameter OD16of the first end plate16, and the outer diameter OD14of the annular member14may be substantially the same as the second outer diameter OD18of the second end plate18. In some particular examples, the first outer diameter OD16of the first end plate16may be about 5.375 inches, and the outer diameter OD14of the annular member14and the second outer diameter OD18of the second end plate18may both be about 5.235 inches. In other examples, the second end plate18may comprise a second outer diameter OD18′that is substantially the same as the first outer diameter OD16of the first end plate16, e.g., about 5.375 inches as shown with dashed lines inFIG. 4.

With reference toFIGS. 1, 4, and 7, the opening20of the collar12may be configured to receive a rotatable shaft100. For example, the inner diameter ID12of the collar12may be slightly larger than an outer diameter OD100of the shaft100, such that the opening20of the collar12receives the shaft100. The first and second end plates16and18may each comprise a respective inner diameter ID16and ID18that may be substantially the same as the inner diameter ID12of the collar12. In some particular examples, the inner diameters ID12, ID16, and ID18of each of the collar12and the end plates16and18may be about 2.470 inches.

The collar12may be configured to be fixedly coupled to the rotatable shaft100such that the collar12rotates with the shaft100. With reference toFIGS. 2 and 7, the collar12may comprise one or more threaded apertures12C extending from the outer surface12-3of the collar12to the inner surface12-4. Set screws (not shown) may be received in the threaded apertures12C and may contact or engage an outer surface100-1of the shaft100with sufficient force to fix the collar12to the shaft100via friction. Coupling of the collar12to the shaft100also prevents axial movement of the collar12with respect to the shaft100, i.e., movement of the collar12in a direction substantially parallel to the axis of rotation A100of the shaft100. The shaft100may be coupled to a motor (not shown) or other primary driver that causes the shaft100to rotate about an axis of rotation A100.

With reference toFIGS. 1, 2, and 4, the collar12comprises one or more helical threads26extending around the outer surface12-3of the collar12, e.g., around an outer circumference of the collar12. The inner surface12-4of the collar12and the outer and inner surfaces14-3and14-4of the annular member14may be substantially smooth, i.e., non-threaded. Each of the one or more helical threads26may extend around the outer surface12-3of the collar12between the first and second end surfaces12-1and12-2of the collar12. In some examples, the one or more helical threads26may comprise a single thread that extends circumferentially about the collar12from the first end surface12-1of the collar12to the second end surface12-2of the collar12. In other examples, the one or more helical threads26may comprise two or more threads that define a multi-start thread. In some particular examples, the helical threads26may comprise a triple start Acme thread having a pitch (distance, measured axially, from a point on one thread to a corresponding point on an adjacent thread) equal to 1 inch (i.e., 1 TPI), a thread depth (from crest to root) of ⅛ inch, and a thread width of ⅛ inch. In other particular examples, the one or more helical threads26may comprise a square thread form, as shown inFIGS. 2 and 4. One or more properties of the one or more helical threads26, e.g., the pitch, depth, etc., may be varied to obtain, for example, a desired number of revolutions around the outer circumference of the collar12, a desired flow rate of a rotary pump generated by the seal assembly10, etc. In general, the one or more helical threads26may be configured such that each thread26extends at least once around an entirety of the outer circumference of the collar12.

The seal assembly10may be used as part of an assembly102to seal a housing104that forms a part of the assembly102. In some examples, as shown inFIGS. 5-7, the assembly102further comprises a bearing assembly114mounted within the housing104, which is also referred to herein as a bearing housing. The assembly102may comprise, for example, a two-piece or split pillow block bearing assembly in which the housing104may comprise an upper portion104A and a lower portion104B that may be joined together by fasteners106, which may comprise threaded bolts or other suitable fasteners. The bearing assembly114(not shown inFIG. 5) supports the rotatable shaft100and allows the shaft100to rotate relative to the housing104. The bearing assembly114may comprise, for example, an outer race114A fixed to an inner portion of the bearing housing104, an inner race114B coupled to the shaft100to rotate with the shaft100, and a plurality of rollers or balls115located between the outer and inner races114A and114B. Each of the outer and inner races114A and114B may comprise two split sections (not labeled), such that a first outer race section is fixed to the upper portion104A of the housing104and a second outer race section is fixed to the lower portion104B of the housing104. The bearing assembly114may comprise, for example, the bearing assembly disclosed in U.S. Pat. No. 4,881,829, the disclosure of which is incorporated herein by reference, or any other conventional shaft supporting bearing assembly. In other examples, the seal assembly10may be used in a different type of sealed housing104, such as a machine or equipment housing, e.g., a gearbox housing, a pump power frame, or a motor frame.

As shown inFIGS. 5 and 7, when the upper and lower portions104A and104B of the housing104are joined together, the housing104may define a first housing opening108and a second housing opening110, in which the second housing opening110may be opposite the first housing opening108. In the example shown inFIGS. 5 and 7, the shaft100extends through both housing openings108and110. A first seal assembly, e.g., seal assembly10, may be received in the first housing opening108, and a second seal assembly, e.g., seal assembly10′, may be received in the second housing opening110. As shown inFIG. 9, in other examples, the shaft100may extend through only one of the housing openings (not visible), and the housing104′ may comprise a cover plate116that extends between the upper and lower portions104A′ and104B′ and across the other housing opening110′ to seal the housing104′. The cover plate116may be secured to the housing104′ by one or more fasteners (not shown). InFIGS. 7 and 9, a sealed chamber118and118′ may be created within the respective housing104and104′ by the upper and lower portions104A/104A′ and104B/104B′ of the housing104/104′, the first seal assembly10, and either the second seal assembly10′ or the cover plate116. In further examples (not shown), the housing may comprise only a single opening, such as when the housing comprises a machine or equipment housing. As shown inFIG. 7, an internal fluid, e.g., grease, oil, and/or other lubricant(s), may be supplied from a fluid supply (not shown) to the sealed chamber118via a conduit120. The fluid may at least partially fill the sealed chamber118and may flow through the bearing assembly114and/or around the shaft100.

The first seal assembly10depicted inFIGS. 5 and 7may be substantially similar to the seal assembly10depicted inFIGS. 1-4. With reference toFIGS. 4 and 7, the outer diameter OD14of the annular member14and the outer diameter OD18of the second end plate18may be slightly less than a diameter D108of the first housing opening108, such that the annular member14and the second end plate18may be received in the first housing opening108. The outer diameter OD16of the first end plate16may be greater than the diameter D108of the first housing opening108, such that the first end plate16is unable to be received in the first housing opening108.

The second seal assembly10′ shown inFIG. 7may comprise a second collar12′, a second annular member14′, and third and fourth end plates16′ and18′. The second collar12′ (also referred to herein as a second annular rotor member) may comprise third and fourth end surfaces12-1′ and12-2′, a second outer surface12-3′, and a second inner surface12-4′. The second inner surface12-4′ of the second collar12′ defines a second opening20′ that receives the shaft100. The second outer surface12-3′ defines a second outer diameter (not labeled) of the second collar12′, and the second inner surface12-4′ defines a second inner diameter (not labeled) of the second collar12′, in which the second inner diameter of the second collar12′ defines a diameter (not labeled) of the second opening20′. Similar to the collar12, the second collar12′ may comprise an axial length (not labeled) defined between the third and fourth end surfaces12-1′ and12-2′, and the second collar12′ may be substantially cylindrical, with the second inner and outer diameters of the second collar12′ being substantially the same along an entirety of the axial length of the second collar12′. The third and fourth end plates16′ and18′ may be fixedly coupled to the second collar12′. In particular, as described in detail with respect to the first and second end plates16and18of the first seal assembly10, the third and fourth end plates16′ and18′ may be fixedly coupled to respective ones of the third and fourth end surfaces12-1′ and12-2′ of the second collar12′ via a plurality of fasteners, as shown inFIGS. 5 and 7(only the fasteners25′ for the fourth end plate18′ are visible).

The second annular member14′ (also referred to herein as a second annular stator member) of the second seal assembly10′ may comprise a separate or discrete ring, as shown inFIGS. 7 and 8B, or may be defined by a portion of the housing104, as described herein with respect toFIG. 11. As described herein with respect to the annular member14, the second annular member14′ may comprise third and fourth end surfaces14-1′ and14-2′, a second outer surface14-3′, and a second inner surface14-4′. The second inner surface14-4′ of the second annular member14′ defines a second annular opening22′ that receives the second collar12′. The second outer surface14-3′ of the second annular member14′ defines a second outer diameter (not labeled) of the second annular member14′, and the second inner surface14-4′ defines a second inner diameter (not labeled) of the second annular member14′, in which the second inner diameter of the second annular member14′ defines a diameter (not labeled) of the second annular opening22′. Similar to the annular member14, the second annular member14′ may comprise an axial length (not labeled) defined between the third and fourth end surfaces14-1′ and14-2′, in which the axial length of the second annular member14′ may be less than the axial length of the second collar12′. The second annular member14′ may be substantially cylindrical, with the inner and outer diameters of the second annular member14′ being substantially the same along an entirety of the axial length of the second annular member14′. As described herein with respect to the annular member14, the second annular opening22′ of the second annular member14′ may similarly be configured to receive the second collar12′.

As shown inFIGS. 7 and 8B, because the axial length of the second annular member14′ is less than the axial length of the second collar12′, the third and fourth end surfaces14-1′ and14-2′ of the second annular member14′ may be spaced apart from respective inner faces16-1′ and18-1′ of the third and fourth end plates16′ and18′, as described herein in detail with respect to the first seal assembly10. Also as described in detail with respect to the first seal assembly10, the third end plate16′ may comprise a third outer diameter (not labeled), and the fourth end plate18′ may comprise a fourth outer diameter (not labeled), in which the fourth outer diameter may be the same as, or less than, the third outer diameter of the third end plate16′. The second outer diameter of the second annular member14′ may be substantially the same as the fourth outer diameter of the fourth end plate18′, as shown inFIG. 7.

Similar to the opening20of the collar12, the second opening20′ of the second collar12′ may be configured to receive the rotatable shaft100, as shown inFIG. 7. In some examples, the second inner diameter of the second collar12′ may be different from the inner diameter ID12of the collar12of the first seal assembly10. For instance, with reference toFIGS. 5 and 7, the shaft100may increase from a first outer diameter OD100to a second outer diameter OD100′within the housing104, such that the second inner diameter of the second collar12′ is greater than the inner diameter ID12of the collar12. In other examples, the outer diameter OD100of the shaft100may be substantially uniform (shown with dashed lines inFIG. 7), such that the inner diameter ID12of the collar12is substantially the same as the second inner diameter of the second collar12′. Inner diameters (not labeled) of the third and fourth end plates16′ and18′ may be substantially the same as the second inner diameter of the second collar12′.

As described in detail with respect to the first seal assembly10, the respective outer diameters of the second annular member14′ and the fourth end plate18′ may be slightly less than a diameter D110of the second housing opening110, such that the second annular member14′ and the fourth end plate18′ may be received in the second housing opening110. An outer diameter (not labeled) of the third end plate16′ may be greater than the diameter D110of the second housing opening110, such that the third end plate16′ is unable to be received in the second housing opening110. In some examples, the diameter D110of the second housing opening110may be substantially the same as the diameter D108of the first housing opening108, such that the outer diameters of the second annular member14′ and the fourth end plate18′ of the second seal assembly10′ are substantially the same as the outer diameters OD14and OD18of the annular member14and the second end plate18of the first seal assembly10, as shown inFIGS. 5 and 7. In other examples (not shown), the diameter D110of the second housing opening110may be different from the diameter D108of the first housing opening108.

The second collar12′ may be configured to be fixedly coupled to the rotatable shaft100such that the second collar12′ rotates with the shaft100. For example, as shown inFIG. 7, the second collar12′ may comprise one or more threaded apertures12C′ that extend from the second outer surface12-3′ of the second collar12′ to the second inner surface12-4′ and receive set screws (not shown) that fix the second collar12′ to the shaft100, as described in more detail with respect to the collar12of the first seal assembly10. Coupling of the second collar12′ to the shaft100also prevents axial movement of the second collar12′ with respect to the shaft100. The second outer surface12-3′ of the second collar12′ may comprise one or more second helical threads26′ that may be substantially similar to the one or more threads26of the collar12and may extend around the second outer surface12-3′ between the third and fourth end surfaces12-1′ and12-2′ of the second collar12′. The second inner surface12-4′ of the second collar12′ and the second outer and inner surfaces14-3′ and14-4′ of the second annular member14′ may be substantially smooth, i.e., non-threaded.

As shown inFIG. 7, the annular members14and14′ may comprise the only portion of each seal assembly10and10′ that contacts the housing104. In some examples, with reference toFIGS. 4 and 7, the axial length L14of the annular member14may be greater than a thickness T104of the adjacent section of the housing104. The axial length of the second annular member14′ may similarly be greater than a thickness T104′of the adjacent section of the housing104.

The annular members14and14′ may be coupled to the housing104such that rotational and axial movement of each annular member14and14′ relative to the rotatable shaft100and/or the housing104is prevented. For example, as shown inFIGS. 4, 5, and 7, when the annular member14comprises a discrete ring, the annular member14may comprise a bore14A that receives a locator pin28extending outwardly from the outer surface14-3of the annular member14substantially perpendicular to the axis of rotation A100of the rotatable shaft100. As shown inFIGS. 5 and 7, the second annular member14′ may similarly comprise a second locator pin28′. The bores14A and locator pins28and28′ may be threaded, or the locator pins28and28′ may engage the bores14A via a friction fit. In some examples, the locator pins28and28′ may comprise a roll pin. The housing104may comprise notches112and112′ configured to receive a respective one of the locator pins28and28′. The notches112and112′ may be formed in any portion of the housing104. In the example shown inFIGS. 5 and 7, the notches112and112′ are formed in a section of the lower portion104B of the housing104. The notches112and112′ may extend axially from inside the housing104toward the outside and may extend only partially through a respective thickness T104and T104′of the housing104and further have a width (not labeled) in a circumferential direction equal to or only slightly larger than a diameter of the pins28and28′ so as to prevent the pins28and28′ from moving circumferentially relative to the housing104. When the annular members14and14′ are received in the respective housing opening108and110, the locator pins28and28′ are inserted into the respect notches112and112′, such that engagement between the locator pins28and28′ and the notches112and112′ prevents rotational movement of the annular members14and14′ relative to the rotatable shaft100and the housing104.

As shown inFIGS. 4 and 7, when the seal assemblies10and10′ are assembled, the collars12and12′ are fixedly coupled to the shaft100, and the end plates16,18and16′,18′ are fixedly coupled to the respective collars12and12′. The annular members14and14′ are then sandwiched between the respective pairs of end plates16,18and16′,18′, which prevents axial movement of the annular members14and14′ relative to the rotatable shaft100. Engagement between the locator pins28and28′ and the respective notches112and112′ may also prevent axial movement of the annular members14and14′ relative to the shaft100and the housing104, e.g., in a direction extending away from the housing104as indicated by arrows DA12and DA12′.

Alternatively, or in addition, rotational and/or axial movement of the annular members14and14′ may be prevented, at least in part, by a friction fit between the outer surfaces14-3and14-3′ of the annular members14and14′ and inner surfaces of the respective housing openings108and110. For example, in some configurations, the outer diameter OD14of the annular member14may be slightly greater than the diameter D108of the first housing opening108, such that when the annular member14is received in the first housing opening108and the upper and lower portions104A and104B of the housing104are closed around the annular member14, the housing104may engage the outer surface14-3of the annular member14by a friction fit. The outer diameter of the second annular member14′ may similarly be slightly greater than the diameter D110of the second housing opening110such that the housing104may engage the second outer surface14-3′ of the second annular member14′ by a friction fit when the second annular member14′ is received in the second housing opening110. In some examples, the housing104may slightly compress the annular members14and14′. In one particular example, the diameters D108and D110of the respective housing openings108and110may be 5.250 inches, and the outer diameters OD14of the respective annular members14and14′ may be about 5.255 inches. In this particular example, the outer diameters OD18of the second and fourth end plates18and18′ may be slightly less than (e.g., about 5.235 inches) the outer diameters OD14of the respective annular members14and14′ and the diameters D108and D110of the respective housing openings108and110so that the second and fourth end plates18and18′ are able to pass through the respective housing openings108and110.

In another example configuration, as shown inFIG. 10, a seal assembly200may comprise an annular member214in the form of a discrete ring comprising a threaded aperture214A that receives a locator pin228. The locator pin228may comprise, for example, a pipe plug. One portion of the pipe plug228may be threaded and may be received in the aperture214A. Another portion of the pipe plug228may extend outwardly from an outer surface (not labeled) of the annular member214substantially perpendicular to an axis of rotation A100of a rotatable shaft100. A housing304may comprise a notch312configured to receive the portion of the pipe plug228that extends outward from the annular member214. The notch312may be formed in any portion of the housing304and may extend partially through a thickness T304of the housing304in an axial direction extending from outside the housing304toward the inside. In some examples, the housing304may comprise a two-part or split housing with upper and lower portions (not labeled) as described herein in detail, and in other examples, the housing304may comprise a single part.

As described herein in detail with respect to the locator pins28and28′ inFIG. 7, when the annular member214with the locator pin228is received in a housing opening308, engagement between the locator pin228and the notch312prevents rotational movement relative to the rotatable shaft100and/or the housing304. Engagement between the locator pin228and the notch312may also prevent axial movement of the annular member214, e.g., in a direction extending toward the housing304. Also as described herein in detail with respect to the annular members14and14′ inFIG. 7, the rotational and/or axial movement of the annular member214relative to the rotatable shaft100and/or the housing304may be prevented, at least in part, by a friction fit between the outer surface of the annular member214and the housing opening308in which the seal assembly200is received. The seal assembly200may be used in conjunction with a second seal assembly, as shown inFIG. 7, or with a cover plate, as shown inFIG. 9, in which the second seal assembly may comprise any of the seal assemblies described herein.

In the example shown inFIG. 10, the seal assembly200may further comprise a collar212and a pair of end plates216and218. The collar212may be fixedly coupled to the rotatable shaft100, as described herein in detail with respect to the collars12and12′ inFIG. 7. For example, the collar212may comprise one or more threaded apertures212C that extend from an outer surface (not labeled) to an inner surface (not labeled) of the collar212and receive set screws (not shown) that fix the collar212to the shaft100, as described herein. Coupling of the collar212to the shaft100allows the collar212to rotate with the shaft100and also prevents axial movement of the collar212with respect to the shaft100. The aperture214A formed in the annular member214may further serve as an access point for removal of the set screws, as described below.

With continued reference toFIG. 10, the seal assembly200may optionally comprise one or more additional O-ring seals238and240. For example, the collar212may comprise an inner groove242that extends circumferentially around the inner surface of the collar212and may be configured to receive a first O-ring seal238. The annular member214may comprise an outer groove244that extends circumferentially around the outer surface of the annular member214and may be configured to receive a second O-ring seal240. The O-ring seals238and240may help to further seal the housing204and prevent entry of material into the housing204between the shaft100and the collar212and/or between the annular member214and the housing opening308, as described below.

In a further configuration, as shown inFIG. 11, a portion of a housing504may define an annular member514. In some instances, the annular member514may be integral with the housing504(e.g., formed as part of the housing504during manufacture) and may comprise a section of the upper and lower portions504A and504B of the housing504. In other instances, the annular member514may be welded or otherwise permanently attached to the housing504. The annular member514defines an annular opening522that receives a collar412of a seal assembly400. The seal assembly400may further comprise first and second end plates416and418, in which the collar412and end plates416and418may be substantially similar in structure to the collar12and end plates16and18depicted inFIGS. 1-4. An outer diameter (not labeled) of the first end plate416may be greater than the diameter D522of the annular opening522, such that the first end plate416is unable to be received in or pass through the annular opening522. Because the annular member514is defined by the housing504, in some examples, an outer diameter (not labeled) of the second end plate418may be substantially the same as an outer diameter (not labeled) of the collar412, and the outer diameters of the collar412and the second end plate418may be slightly less than a diameter D522of the annular opening522defined by the annular member514, such that the collar412and the second end plate418may be received in the annular opening522. In other examples, the outer diameter of the second plate418may be substantially the same as the outer diameter of the first end plate416. As described herein in detail with respect to the collars12and12′ inFIG. 7, the collar412may be fixedly coupled to the rotatable shaft100to allow rotation of the collar412with the shaft100and to prevent axial movement of the collar412with respect to the shaft100. The seal assembly400may be used in conjunction with a second seal assembly, as shown inFIG. 7, or with a cover plate, as shown inFIG. 9, in which the second seal assembly may comprise any of the seal assemblies described herein.

With reference toFIGS. 1 and 4-7, the seal assembly10may be mounted to the shaft100and installed in the housing104as follows. One of the end plates, e.g., the second end plate18, may be fixedly coupled to the second end surface12-2of the collar12, as described herein. The collar12with the attached end plate18may be placed on and fixedly coupled to the shaft100by screwing the set screws (not shown) into the threaded apertures12C formed in the collar12until the set screws contact or engage the outer surface100-1of the shaft100, thereby fixing the collar12to the shaft100via friction. The annular member14may be placed around the shaft100and over the outer surface12-3of the collar12such that the annular member14is adjacent to the second end plate18. The other end plate, e.g., the first end plate16, may be placed around the shaft100and fixedly coupled to the first end surface12-1of the collar12, as described herein. The upper portion104A of the housing104may be separated from the lower portion104B, and the shaft100with the installed seal assembly10may be placed in the lower portion104B of the housing104such that the annular member14is received in a lower half of the housing opening108defined by the lower portion104B of the housing104and the locator pin28is received in the notch112. The interaction between the locator pin28and the notch112may act as a stop to help position the seal assembly10correctly in the housing opening108. The upper portion104A of the housing104may then be attached to the lower portion104B of the housing104, such that the annular member14is received in an upper half of the housing opening108defined by the upper portion104A of the housing104. As shown inFIGS. 6 and 7, following installation, the first end plate16is located outside the housing104, and the second end plate18is located inside the housing104, with the collar12and the annular member14extending from outside the housing104to inside the housing104. If desired, the second seal assembly10′ may be mounted to a second location on the shaft100and installed in the second housing opening110in a similar manner.

To remove the seal assembly10, the upper portion104A of the housing104may be separated from the lower portion104B, and the shaft100with the seal assembly10may be removed from the housing104. One of the end plates, e.g., the first end plate16, may be removed from the collar12, and the annular member14may be removed. The collar12may be uncoupled from the shaft100and removed (the second end plate18may be removed or may remain attached to the collar12). If present, the second seal assembly10′ may be removed in a similar manner.

In configurations in which the housing is one part or it is not feasible to separate the upper and lower portions104A and104B of a split housing104, it may be desirable to use the configuration shown inFIG. 10in which the notch312that receives the locator pin228extends axially from outside the housing304toward the inside. In some examples, the seal assembly200may be coupled to the shaft100, as described above with respect to the seal assembly10. In other examples, the seal assembly200may be assembled separate from the shaft100by attaching one of the end plates, e.g., the second end plate218, to the collar212, placing the annular member214over the collar212, and attaching the other end plate, e.g., the first end plate216, to the collar212. The seal assembly200may then be placed around the shaft100. The locator pin228(i.e., the pipe plug) may be removed, i.e., unscrewed, from the aperture214A in the annular member214, and the annular member214may be rotated until the aperture214A is aligned with one of the apertures212C formed in the collar212, as shown inFIG. 10. The set screw (not shown) located in the aperture212C may be accessed via the aperture214A and may be screwed into the aperture212C until the set screw contacts or engages the outer surface100-1of the shaft100. This process may be repeated with all of the apertures212C and respective set screws until the collar212is fixedly coupled to the shaft100via friction.

With continued reference toFIG. 10, the shaft100with the seal assembly200may be inserted into the housing opening308, with the second end plate218facing the housing304. The outer diameters of the annular member214and the second end plate218may be substantially the same and may be configured such that the shaft100with the seal assembly200is able to be inserted into the housing opening308without the need to open the housing304. The locator pin228may be received in the notch312, with the interaction between the locator pin228and the notch312acting as a stop to position the seal assembly200correctly in the housing opening308.

To remove the seal assembly200shown inFIG. 10, the shaft100with the seal assembly200may be at least partially removed from the housing304(e.g., by moving the shaft100axially away from the housing304or removing the upper portion304A of the housing304) so that the locator pin228is accessible. The locator pin228may be removed, i.e., unscrewed, from the aperture214A, and the annular member214may be rotated until the aperture214A is aligned with one of the apertures212C formed in the collar212, as shown inFIG. 10. The set screw coupling the collar212to the shaft100may be accessed via the aperture214A and may be unscrewed from the shaft100. This process may be repeated until all of the set screws have been unscrewed from the shaft100and the collar212is uncoupled from the shaft100. The entire seal assembly200may then be removed from the shaft100without the need to first remove one of the end plates216or218and the annular member214.

Seal assemblies in accordance with the present disclosure may be configured such that when the rotatable shaft100rotates, an interaction between the outer surface of the collar (i.e., the helical threads) and an inner surface of the annular opening creates or defines a rotary pump (i.e., a screw pump) with an axial flow direction extending from inside the housing (i.e., from inside the sealed chamber118) to outside the housing. With reference to the first seal assembly10depicted inFIGS. 7 and 8A(all components except for the collar12are depicted in cross-section inFIG. 8A), the one or more helical threads26of the collar12may be configured such that when the rotatable shaft100rotates in a direction into the paper, an interaction between the outer surface12-3of the collar12and an inner surface of the annular opening22(i.e., the inner surface14-4of the annular member14) creates a first rotary pump with a first axial flow direction indicated by arrow DA12(e.g., from right to left). With reference to the second seal assembly10′ depicted inFIGS. 7 and 8B(all components except for the second collar12′ are depicted in cross-section inFIG. 8B), the one or more second helical threads26′ of the second collar12′ may be configured such that when the rotatable shaft100rotates into the paper, an interaction between the second outer surface12-3′ of the second collar12′ and an inner surface of the second annular opening22′ (i.e., the second inner surface14-4′ of the second annular member14′) creates a second rotary pump with a second axial flow direction indicated by arrow DA12′(e.g., from left to right), in which the second axial direction DA12′is opposite the first axial direction DA12. A directionality of the helical threads26and26′ may be used to control the direction of fluid movement, with the second helical threads26′ comprising an opposite directionality as compared to the helical threads26of the first seal assembly10. For example, the one or more helical threads26of the collar12may comprise one of a right-handed thread or left-handed thread, and the one or more second helical threads26′ of the second collar12′ may comprise the other of the right-handed thread or the left-handed thread. In the examples shown inFIGS. 8A and 8B, the collar12comprises a left-handed thread, and the second collar12′ comprises a right-handed thread.

As shown inFIGS. 4 and 8Awith respect to the first seal assembly10, the second end surface14-2of the annular member14may be spaced apart from the inner face18-1of the second end plate18(e.g., by the second distance D2) to define an inlet30, and the first end surface14-1of the annular member14may be spaced apart from the inner face16-1of the first end plate16(e.g., by the first distance D1) to define an outlet32. The inlet30and the outlet32may extend circumferentially about an entirety of the respective end surfaces14-1and14-2of the annular member14and the adjacent sections of the inner faces16-1and18-1of the respective end plates16and18. When the rotatable shaft100rotates, the collar12and the end plates16and18rotate with the shaft100, and the annular member14is held stationary with respect to the shaft100, the housing104, the collar12, and the end plates16and18. Interaction between the one or more helical threads26formed on the outer surface12-3of the collar12and the inner surface14-4of the annular member14generates the rotary pump action effecting movement of contaminants and fluids in the first axial direction DA12that extends from the inlet30toward the outlet32.

In particular, each of the one or more helical threads26comprises a corresponding helical groove27defined between neighboring threads26, as shown inFIG. 8A. Each helical groove27may comprise an entrance27A and an exit27B. For example, a triple start thread would comprise three entrances and three exits equally spaced circumferentially about the end surfaces12-1and12-2of the collar12(only one entrance and one exit are visible inFIG. 8A; seeFIG. 2). The entrance27A may be located near the second end surface12-2of the collar12and may be in fluid communication with the inlet30. The exit27B may be located near the first end surface12-1of the collar12and may be in fluid communication with the outlet32. Fluid entering the inlet30from inside the sealed chamber118would enter the one of the helical grooves27at the entrance27A, and the action of the rotary pump would cause the fluid to move in the first axial direction DA12through the groove27. Continued action of the rotary pump would cause the fluid to pass out of the groove27at the exit27B and to be discharged from the seal assembly10at the outlet32, after which the fluid enters an area134outside the housing104.

The action of the rotary pump prevents contaminants136from entering the housing104through the outlet32. One or more contaminants136, such as water or other liquids, dirt, sand, wood pulp, black liquor, etc. may be present in the area134outside the housing104and may attempt to enter the outlet32, i.e., by moving in a direction opposite to the first axial flow direction DA12of the rotary pump. The action of the rotary pump may counteract the ingress of the contaminants136and prevent them from entering the housing104, as well as helping to expel any contaminants136present in, for example, the grooves27. In some examples, the seal assembly10as shown inFIGS. 7 and 8Amay comprise a “dry” seal that does not require the use of a barrier or flushing fluid to exclude and/or expel contaminants136, i.e., little or no internal fluid from the sealed chamber118is present in the grooves27and/or outlet32. In this example, the sealed chamber118may generally be unpressurized (i.e., at atmospheric pressure). In other examples, as shown in the detailed view of a portion of a seal assembly600inFIG. 12, a port720may be formed in a housing704and may be utilized to inject a viscous fluid (i.e., grease) either continuously or intermittently into a space between an annular member614and a collar612of the seal assembly600. This fluid would provide a medium for the seal assembly600to pump and may serve as a flushing or barrier fluid that helps to ensure that the seal assembly600, i.e., the grooves627, are filled with fluid during operation and when shut down, i.e., when the rotatable shaft (not shown; seeFIG. 7) is not rotating. The fluid may also help to reduce the flow of lower viscosity fluids (oil) from inside the housing704to the outside. In both examples, the helical threads26and626as shown inFIGS. 8A and 12create an indirect path between the respective inlet30,630and outlet32,632that helps to prevent the ingress of contaminants136(not shown inFIG. 12).

With reference to the second seal assembly10′ shown inFIGS. 7 and 8B, the one or more second helical threads26′ of the second collar12′ may likewise be configured such that when the rotatable shaft100rotates, an interaction between the second outer surface12-3′ of the second collar12′ and the second inner surface of the second annular opening22′ (i.e., the second inner surface14-4′ of the second annular member14′) creates a second rotary pump action effecting movement of contaminants and fluids in the second axial flow direction DA12′extending from inside the housing104to outside the housing104, in which the second axial flow direction DA12′is opposite to the first axial flow direction DA12. The third and fourth end surfaces14-1′ and14-2′ of the second annular member14′ may be spaced apart from the respective third and fourth inner faces16-1′ and18-1′ of the third and fourth end plates16′ and18′ to define a respective second inlet30′ and second outlet32′. The second inlet30′ and the second outlet32′ may extend circumferentially about an entirety of the respective end surfaces14-1′ and14-2′ of the second annular member14′ and the adjacent sections of the inner faces16-1′ and18-1′ of the respective end plates16′ and18′. When the rotatable shaft100rotates, the second collar12′ and the end plates16′ and18′ rotate with the shaft100, and the second annular member14′ is held stationary with respect to the shaft100, the housing104, the second collar12′, and the end plates16′ and18′. An interaction between the one or more second helical threads26′ formed on the outer surface12-3′ of the second collar12′ and the inner surface14-4′ of the annular member14′ generates the second rotary pump with the second axial flow direction DA12′extending from the second inlet30′ toward the second outlet32′.

Similar to the helical threads26of the first collar12, each of the one or more second helical threads26′ may comprise a corresponding helical groove27′ defined between neighboring threads26′, as shown inFIG. 8B. Each helical groove27′ may comprise an entrance27A′ and an exit27B′. The entrance27A′ may be located near the fourth end surface12-2′ of the second collar12′ and may be in fluid communication with the second inlet30′. The exit27B′ may be located near the third end surface12-1′ of the second collar12′ and may be in fluid communication with the outlet32′. Fluid entering the inlet30′ from inside the sealed chamber118would enter one of the helical grooves27′ at the entrance27A′, and the action of the rotary pump would cause the fluid to move in the second axial flow direction DA12′through the groove27′ toward the exit27B′, where the fluid is discharged from the second seal assembly10′ at the outlet32′ and enters the area134outside the housing104.

The action of the second rotary pump helps to prevent contaminants136from entering the housing104through the outlet32′ (i.e., in a direction opposite to the second axial flow direction DA12′of the second rotary pump). As described herein in detail with respect to the seal assemblies10and600inFIGS. 8A and 12, The second seal assembly10may operate as a “dry” seal, as described with respect to the first seal assembly10inFIG. 8A, or may be used in conjunction with an intermittent or continuous supply of a fluid, as described with respect toFIG. 12.

Any of the seal assemblies described herein may optionally include one or more additional seals, such as the O-ring seals238and240depicted inFIG. 10. The O-ring seals238and240may help to prevent contaminants from entering the housing at, for example, an interface (not labeled) between an outer surface of the shaft and the inner surface of the collar and/or an interface (not labeled) between the outer surface of the annular member and the housing opening. Alternatively, or in addition, any of the seal assemblies described herein may also be used in conjunction with one or more conventional seals, such as a labyrinth seal (not shown).

Although exemplary dimensions are provided herein for the inner diameter, outer diameter, axial length, etc. of some components of the seal assemblies, it is understood that the components of the seal assemblies may comprise any suitable dimension needed to provide the described relationships and/or interactions between the components of the seal assembly and/or between the seal assembly and the housing in which the seal assembly is received. In addition, although the components of the seal assemblies described herein are depicted as comprising a single part, it is understood that one or more of the components (e.g., the collar, the annular member, and/or the end plates) could comprise two or more parts, such as an upper and lower portion, to simplify assembly and removal. Furthermore, while the end plates are depicted herein as separate components, one or both of the end plates may optionally be formed as part of the collar.

As described herein, seal assemblies in accordance with the present disclosure harness the energy of a rotating shaft to generate a seal that excludes and/or expels contaminants attempting to enter the housing. When the seal assembly is installed, helical threads on the outer surface of the collar and an inner surface of a corresponding annular member define a rotary pump (i.e., a screw pump) effecting an axial flow direction extending from inside the housing to outside the housing. The action of the rotary pump serves to expel contaminants attempting to enter the housing, i.e., contaminants attempting to move in a direction opposite to the axial flow direction of the rotary pump. This design may help to increase the useful life of the housing and components, e.g., bearings, within the housing, particularly in high contamination environments where conventional seals may wear out too quickly or be overwhelmed. Seal assemblies in accordance with the present disclosure may be configured to fit a variety of types and sizes of shafts and housings and may be configured to allow for easy installation and removal, as described herein. The seal assembly design includes a minimum of operational components and is not dependent on tight tolerances and precision machined fits to function properly. The presently disclosed seal assembly design may also be particularly useful in situations involving shaft deflection. Shaft deflection may interfere with and/or damage conventional contact or labyrinth seals. Seal assemblies in accordance with the present disclosure are designed to operate with a small amount of clearance between the stator member, i.e., the collar, and the rotor member, i.e., the annular member, such that shaft deflection is less likely to damage the seal assembly and/or interfere with the ability of the seal assembly to effectively exclude and/or expel contaminants.

FIGS. 13 and 14are flowcharts of exemplary methods800and900for preventing contamination of a sealed chamber, in accordance with the present disclosure. Although reference is made primarily to the seal assemblies10and10′ and the housing104shown inFIGS. 1-7, 8A, and 8B, it is understood that the disclosed methods may be used with any of the configurations described herein.

With reference toFIG. 13, the method800begins at Step802with fixedly coupling an annular rotor member to a rotatable shaft such that axial movement of the annular rotor member relative to the rotatable shaft is prevented, in which an outer surface of the annular rotor member comprises one or more helical threads. As shown inFIGS. 4 and 7, the annular rotor member may comprise, for example, the collar12, which may be fixedly coupled to the rotatable shaft100as described herein in detail. The outer surface12-3of the collar12may comprise one or more helical threads26.

The method800continues at Step804with providing an annular stator member that is fixedly coupled to a housing such that rotational and axial movement of the annular stator member relative to the rotatable shaft is prevented. As shown inFIGS. 4 and 7, the annular stator member may comprise, for example, the annular member14, which may be fixedly coupled to the housing104as described herein in detail. In other examples, as shown inFIG. 11, the annular member514may be defined by a portion of the housing504. The housing may comprise a bearing housing or a machine or equipment housing, as described herein.

At Step806, the rotatable shaft is inserted into the housing such that the outer surface of the annular rotor member is adjacent to an inner surface of the annular stator member to generate the sealed chamber. With reference toFIG. 7, the rotatable shaft100may be inserted into the housing104such that the outer surface12-3of the collar12is adjacent to the inner surface14-4of the annular member14, which may generate the sealed chamber118in the housing104. As shown inFIG. 11, when a portion of the housing504defines the annular member514, the rotatable shaft100may similarly be inserted into the housing504such that the outer surface (not labeled) of the collar412is adjacent to the inner surface (not labeled) of the annular member514.

The method800continues at Step808with rotating the rotatable shaft, in which the one or more helical threads are configured such that an interaction between the outer surface of the annular rotor member and the inner surface of the annular stator member generates a rotary pump comprising a first axial flow direction extending from inside the housing to outside the housing and prevents material from entering the sealed chamber. The method800may conclude following Step808. With reference toFIGS. 7 and 8A, the rotatable shaft100may be coupled to a motor (not shown) that causes the shaft100to rotate, and the one or more helical threads26of the collar12may be configured such that an interaction between the outer surface12-3of the collar12and the inner surface14-4of the annular member14generates a rotary pump action effecting movement of contaminants, fluids and the like in a first axial flow direction DA12extending from inside the housing104to outside the housing104and prevents material, e.g., contaminants136, from entering the sealed chamber118.

FIG. 14illustrates additional optional steps that may be performed during or after the method800depicted inFIG. 13. With reference toFIG. 14, the method900begins at Step902with fixedly coupling a second annular rotor member to the rotatable shaft such that axial movement of the second annular rotor member relative to the rotatable shaft is prevented, in which an outer surface of the second annular rotor member comprises one or more second helical threads. As shown inFIG. 7, the second annular rotor member may comprise, for example, the second collar12′, which may be fixedly coupled to the rotatable shaft100as described herein in detail. The outer surface12-3′ of the second collar12′ may comprise one or more second helical threads26′.

The method900continues at Step904with providing a second annular stator member that is fixedly coupled to the housing such that rotational and axial movement of the second annular stator member relative to the rotatable shaft is prevented. The method900may conclude following Step904. As shown inFIG. 4, the second annular stator member may comprise, for example, the second annular member14′, which may be fixedly coupled to the housing104as described herein in detail. As shown inFIG. 7, when the rotatable shaft100is inserted into the housing104, the outer surface12-3′ of the second collar12′ is adjacent to the inner surface14-4′ of the second annular member14′, which may generate the sealed chamber118in the housing104. In other examples, as shown inFIG. 11, the second annular member514may be defined by a portion of the housing504, and when the rotatable shaft100is inserted into the housing504, the outer surface (not labeled) of the collar412is adjacent to the inner surface (not labeled) of the annular member514. With reference toFIGS. 7 and 8B, the rotatable shaft100may be coupled to a motor (not shown) that causes the shaft100to rotate, and the one or more second helical threads26′ of the second collar12′ may be configured such that when the rotatable shaft100rotates, an interaction between the outer surface12-3′ of the second collar12′ and the inner surface14-4′ of the second annular member14′ generates a second rotary pump comprising a second axial flow direction DA12′extending from inside the housing104to outside the housing104and prevents material, e.g., contaminants136, from entering the sealed chamber118. The second axial flow direction DA12′is opposite the first axial flow direction DA12.

As used throughout, ranges are used as a short hand for describing each and every value that is within the range, including all subranges therein.