Patent Description:
Valves often develop leaks as they age. Leaking valves can be annoying, wasteful, and can cause damage in residential settings, but can be far more problematic in industrial applications. Factory lines may need to be shutdown to repack or replace valves resulting in lost production and unnecessary downtime. Leaks can cause environmental damage and safety issues. Steam leaks can scald and even kill workers. The Environmental Protection Agency (EPA) is concerned about pollution resulting from leaky valve stem seals in factories and oil fields. In extreme cases, such as semiconductor manufacturing, even microscopic leaks can be fatal - breathing tanks and hazmat suits are often required to clean up after leaks are detected in semiconductor foundries.

Most traditional valves usually have two moving seals: (<NUM>) the Seat where the flow of material through the valve is allowed, controlled, and shut off, and (<NUM>) the Stem seal that keeps the material from leaking out of the hole for the valve handle. Studies have shown that some high percentage of the leaks encountered in real world valves are associated with the stem seals because they tend to entrain dirt and grit which can erode the mating surfaces over time.

Traditional valves contain stem seals that often degrade or leak over time. Previous seal-less valves often employed bending or flexing components such as bellows or membranes that can degrade or fatigue and also leak long term. Additionally, previous generations of magnetic valves usually contained internal magnets and/or operated in a linear solenoid type manner making high temperature operation difficult to achieve, and often requiring continuous power to maintain their position.

<CIT> relates to magnetically operated rotary valves which are intended to be leakproof and noiseless in their operation and which may be manually operated or adapted remote control. <CIT> discloses a method and system for supplying a cleaning gas into a process chamber. <CIT> discloses taps and their mechanical control.

Systems and methods are provided for magnet-actuated valves with external magnets and internal magnetic flux paths.

The invention is defined by a valve according to claim <NUM> and the corresponding method for magnetically actuating a valve according to claim <NUM>. Further aspects of the invention are detailed in the dependent claims.

Still other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description, which describes embodiments illustrating various examples of the invention. As will be realized, the invention is capable of other and different embodiments and its several details are capable of modifications in various respects, all without departing from the scope of the claims.

In the following description, reference is made to the accompanying drawings that illustrate several embodiments of the present disclosure. It is to be understood that other embodiments may be utilized and system or process changes may be made without departing from the spirit and scope of the present disclosure. The following detailed description is not to be taken in a limiting sense, and the scope of the embodiments of the present invention is defined only by the claims of the issued patent. It is to be understood that drawings are not necessarily drawn to scale.

Various embodiments of the present disclosure provide improved systems and methods for actuating valves using an external magnet and internal magnetic flux path. These embodiments may provide improved durability and leak-resistance, as well as overcoming various technical challenges presented when using conventional magnetic valves.

<FIG> depicts a cross-sectional side view of a magnet-actuated valve assembly <NUM>, in accordance with various aspects of the present disclosure. Valve assembly <NUM> includes a body <NUM>. Body <NUM> may be the outer casing of valve assembly <NUM> and may comprise any desired material depending on the desired application for the particular valve assembly <NUM>. In various examples, body <NUM> may comprise various metallic materials such as brass, copper, steel, bronze, gunmetal, alloy steels, non-<NUM> series stainless steels, iron or the like. In some examples, body <NUM>, or portions of body <NUM>, may comprise a metal that has a low magnetic permeability. In some examples, portions of body <NUM> (e.g., the portion of body <NUM> in <FIG> depicted above and/or surrounding cavity <NUM>) may comprise a material with a low magnetic permeability in order to avoid shunting magnetic flux through the body of the valve, thereby weakening the magnetic actuation mechanism described herein. In some examples, the portion of body <NUM> adjacent to cavity <NUM> may comprise a metal that has a low magnetic permeability. For example, the metal may comprise aluminum, copper, titanium, and alloys thereof, and may exhibit a relative magnetic permeability (e.g., the ratio of magnetic permeability of a material vs. the magnetic permeability of free space) less than <NUM>. In some embodiments the metal may exhibit a relative magnetic permeability of about <NUM>. In still other examples, body <NUM> may comprise one or more plastics and/or composite materials. Different materials may be selected for body <NUM> depending on the desired application for the valve assembly <NUM>. For example, materials may be selected for body <NUM> of valve <NUM> which are resistant to corrosion, heat, moisture, rust, and/or bacterial growth.

Valve assembly <NUM> may include a stem <NUM>. Stem <NUM> may transmit motion from a handle, actuator, and/or other controlling device to a movable valve member <NUM>. For example, in a ball valve (e.g., a valve in which valve member <NUM> is a ball, as depicted in <FIG>), stem <NUM> may be operatively coupled to the ball such that rotating the stem <NUM> using a handle or other actuator of the valve may, in turn, rotate the ball between an open position and a closed position to control a flow of fluid through the valve. Various types of valves along with their corresponding actuation mechanisms and valve members (sometimes referred to as "discs") may be used in accordance with embodiments of the present disclosure. In a few examples, gate valves, ball valves, globe valves, butterfly valves, plug valves, poppet valves, needle valves, and/or spool valves may be used in accordance with embodiments of the present disclosure depending on the desired valve type.

Body <NUM> of valve assembly <NUM> may be formed in such a way as to define an enclosure such as cavity <NUM> depicted in <FIG>. In some examples, cavity <NUM> may be formed from a portion of body <NUM> with a smaller diameter and/or cross-sectional width relative to other portions of valve body <NUM>. Additionally, in some examples, portions of body <NUM> defining cavity <NUM> may be relatively thin so as to transmit magnetic flux from external magnets <NUM> into cavity <NUM>. For example, portion <NUM> and portion <NUM> may be of a thickness such that magnetic flux passes from external magnet 106a, through internal actuation member <NUM>, and to external magnet 106b. Although portions <NUM> and <NUM> of body <NUM> are described as being separate portions of body <NUM>, it should be appreciated that body <NUM> may be a continuous material enclosing and sealing internal actuation member <NUM> within cavity <NUM>. In valve assembly <NUM>, stem <NUM> may be entirely contained within the body <NUM> of the valve assembly <NUM> such that no portion of the stem <NUM> extends outside of body <NUM>.

In some examples, cavity <NUM> may be cylindrical. In various further examples, external actuator <NUM> may comprise an annular base portion concentric with the cylindrical cavity <NUM>. External magnets 106a, 106b may be disposed on a first portion of the annular base portion of external actuator <NUM>. A first magnetic pole section (the south pole of external magnet 106a, in <FIG>) of external magnet 106a may be disposed adjacent to a first location of the annular base portion of external actuator <NUM>. Similarly, a second magnetic pole section (the north pole of external magnet 106b, in <FIG>) of external magnet 106b may be disposed adjacent to a second location of the annular base portion of external actuator <NUM>.

Internal actuation member <NUM> may be mechanically coupled to stem <NUM>. Accordingly, rotation of internal actuation member <NUM> may rotate stem <NUM>, which may, in turn, actuate movement of valve member <NUM> between an open position and a closed position in seat <NUM>. As depicted in <FIG>, internal actuation member <NUM> may be enclosed within cavity <NUM> such that internal actuation member <NUM> is not exposed to the exterior of body <NUM> of valve <NUM>. Internal actuation member <NUM> may comprise a material having a high magnetic permeability such that magnetic flux flows from an external magnet (such as, for example, external magnets 106a, 106b) through internal actuation member <NUM> and returns to either the same external magnet or a different external magnet. In some examples, internal actuation member <NUM> may comprise one or more ferromagnetic materials such as iron, nickel, cobalt and/or alloys thereof. In another example, internal actuation member <NUM> may comprise <NUM> series stainless steel. Although internal actuation member <NUM> may comprise one or more materials having high magnetic permeability, in various examples, ferromagnetic actuation member may not be a permanent magnet and may not necessarily include permanent magnets. Internal actuation member <NUM> and/or materials of internal actuation member <NUM> may be temporarily magnetized while internal actuation member <NUM> is exposed to magnetic fields of magnetic pole sections of external magnets 106a, 106b.

In some examples, internal actuation member <NUM> may be non-radially symmetric. For example, internal actuation member <NUM> may comprise an elongate member with a first end aligned with a first magnetic pole section of external magnet 106a and a second end aligned with a second magnetic pole section of magnet 106b, in a preferred orientation. Additionally, in some examples, internal actuation member <NUM> may comprise a material of high magnetic permeability, such as iron or <NUM> series stainless steel, embedded within a material of low magnetic permeability, such as ceramic. In some examples, the embedded material may form a path within the ceramic material such that magnetic flux flows along the path when a magnetic field interacts with internal actuation member <NUM>.

In some examples, external actuator <NUM> may comprise a handle, lever, or other actuation mechanism effective to rotate external magnets 106a, 106b around body <NUM>. In various examples, motors may be used to turn the handle and/or control actuation of external actuator <NUM>. Generally, when the handle is not being turned or otherwise actuated, the internal actuation member <NUM> maintains its current position and thus the valve member <NUM> remains in its current state. Although external actuator <NUM> is depicted in <FIG> as being above the valve body <NUM>, in some examples, external actuator <NUM> may be in-plane with magnets 106a, 106b or underneath magnets 106a, 106b. In some examples, external actuator <NUM> may comprise a ferromagnetic material to form a return flow path for magnetic flux flowing from external magnet 106a, through internal actuation member <NUM>, to magnet 106b, and through ferromagnetic external actuator <NUM> to return to external magnet 106a. It should be appreciated that in various other examples, magnetic flux may flow from external magnet 106b, through internal actuation member <NUM>, to magnet 106a, and through ferromagnetic external actuator <NUM> to return to external magnet 106b.

Magnetic flux from external magnets 106a, 106b may be effective to orient internal actuation member <NUM> in a preferred orientation with respect to the magnetic pole sections of external magnets 106a, 106b.

In still other examples described in further detail below, external magnet 106a may include a north pole section and south pole section. In such an example, magnetic flux may flow from the north pole section of external magnet 106a, through a flux path in internal actuation member <NUM>, and return from internal actuation member <NUM> to the south pole section of external magnet 106a. Similarly, in another example, external magnet 106b may include a north pole section and south pole section. In such an example, magnetic flux may flow from the north pole section of external magnet 106b, through a flux path in internal actuation member <NUM>, and return from internal actuation member <NUM> to the south pole section of external magnet 106b.

External magnets 106a and 106b may comprise, for example, permanent magnets such as Neodymium Iron Boron magnets, Samarium Cobalt magnets, Alnico magnets, Ceramic and/or Ferrite magnets. Examples of different Neodymium magnets may include N42, N52, and N42SH grade Neodymium magnets. Different magnets may exhibit different magnetic field strengths (in terms of Gauss and/or Teslas) and different pull forces. As such, different magnets may produce different amounts of torque in internal actuation member <NUM> when the magnets are rotated around the exterior of cavity <NUM>. In some examples, external magnets 106a and/or 106b may comprise combinations of different permanent magnets. Additionally, in some examples, external magnets 106a and/or 106b may comprise electromagnets.

External magnets 106a and/or 106b may exhibit different Curie temperatures depending on the particular types of magnets used. A Curie temperature is the temperature at or above which a magnet becomes demagnetized. After the temperature of a magnet drops below the Curie temperature, the magnet may no longer behave as it did prior to reaching the Curie temperature, or temperatures above the Curie temperature. In the examples described in the present disclosure, magnets are included in the external portions of the various valves, but may not be included within body <NUM> or cavity <NUM>. Such a configuration may be advantageous if the valves are welded, soldered, and/or brazed during installation and/or repair. If the valves are to be subjected to temperatures above the Curie temperature for the particular external magnets, the external magnets may be removed prior to heating the valve in order to avoid demagnetizing the external magnets. The external magnets may thereafter be reattached after the valve has returned to the rated operating temperature range for the particular external magnets used with the valve. The valve may thereafter be actuated using the various techniques described in the present disclosure. In some examples, body <NUM> of valve assembly <NUM> and/or the external magnets 106a, 106b may be heat-shielded using insulating materials to prevent hot material passing through the valves (e.g., steam or other hot liquids) from demagnetizing the external magnets 106a, 106b. In some other examples, valves in accordance with the present disclosure may include one or more heat sinks (such as radiators and/or fins) to dissipate heat caused by hot material passing through the valves in order to prevent demagnetization of external magnets 106a, 106b.

Because internal actuation member <NUM> is not a permanent magnet, internal actuation member <NUM> may be heated without losing its ferromagnetic properties. Additionally, by sealing stem <NUM> within body <NUM> of valve assembly <NUM>, a stem seal is avoided. A stem seal is an interface through which a stem passes between the interior of a valve and the exterior of the valve. Dirt and/or other contaminants can be introduced at the stem seal and can cause a leak in the stem seal. As such, for many applications it may be advantageous to seal the stem within the body of the valve assembly <NUM>, as described herein.

Valve <NUM> may include ports <NUM> and <NUM>. Although in the example depicted in <FIG>, two ports are shown, more ports may be used depending on the particular valve. Ports <NUM> and <NUM> may be inlet and/or outlet ports. Additionally, in some examples, ports <NUM> and <NUM> may be interchangeable as inlet ports and outlet ports depending on the way valve <NUM> is installed in a system.

<FIG> depict a magnetic flux path through a magnet-actuated valve including two external magnets, in accordance with various aspects of the present disclosure. In <FIG>, magnetic flux is depicted using magnetic flux lines <NUM> with arrows showing the direction of flow in the magnetic flux path. In <FIG>, internal actuation member <NUM> has an elongate, rectangular bar shape with a longer length and a shorter width. As depicted in <FIG>, internal actuation member <NUM> is aligned along its length with magnets 106a and 106b.

Magnetic flux may flow from the north pole section of external magnet 106a. Magnetic flux may flow into body <NUM>, through internal actuation member <NUM>, out of body <NUM>, and into the south pole section of external magnet 106b. External actuator <NUM> may comprise a ferromagnetic material and the magnetic flux may flow through external actuator <NUM> to return to the south pole section of external magnet 106a.

In <FIG> external actuator <NUM> has been rotated such that external magnets 106a and 106b have become misaligned with respect to rod-shaped internal actuation member <NUM>. External magnets 106a and 106b create a magnetic flux path through internal actuation member <NUM> resulting in a restoring torque causing internal actuation member <NUM> to rotate to align with magnets 106a and 106b, as depicted in <FIG>. Accordingly, rotating external actuator <NUM> causes a change in direction of the magnetic flux path. Internal actuation member <NUM> experiences a restoring torque causing internal actuation member <NUM> to rotate inside cavity <NUM> to stay in alignment with the magnetic flux path created by external magnets 106a and 106b. Alignment of internal actuation member <NUM> with respect to external magnets 106a, 106b and the magnetic flux path results in the lowest magnetic reluctance vis-à-vis misaligned orientations of the internal actuation member <NUM> with respect to external magnets 106a, 106b. For example, when external actuator <NUM> is in the rotational position relative to internal actuation member <NUM> depicted in <FIG>, there may be a relatively high magnetic reluctance experienced by internal actuation member <NUM>. When external actuator <NUM> is in the rotational position relative to internal actuation member <NUM> depicted in <FIG>, there may be relatively low magnetic reluctance experienced by internal actuation member <NUM>. When the external actuator <NUM> is in the rotational position with respect to internal actuation member <NUM> that is depicted in <FIG>, a magnetic flux path from the north pole of external magnet 106a, through the ferromagnetic portion of internal actuation member <NUM>, to the south pole of external magnet 106b may have a magnetic field strength sufficient to cause rotation of the stem when the external actuator <NUM> is rotated.

As described above, rotation of external actuator <NUM> (and thus external magnets 106a, 106b) may cause corresponding rotation of internal actuation member <NUM>. Rotation of internal actuation member <NUM> may actuate stem <NUM> (depicted in <FIG>) which may, in turn, actuate movement of valve member <NUM> (depicted in <FIG>) between the open and closed position or between the closed and open position, depending on the direction of rotation of internal actuation member <NUM>.

In the embodiment depicted in <FIG>, the width of internal actuation member <NUM> corresponds to the width of external magnets 106a and 106b. Matching and/or approximating the dimensions of those portions of internal actuation member <NUM> that are disposed at the interface with the external magnets when the internal actuation member <NUM> is in its lowest reluctance, aligned state, may increase the torque produced when external actuator <NUM> is rotated.

<FIG> depict a magnetic flux path through a magnet-actuated valve including an external magnet <NUM>, in accordance with various aspects of the present disclosure. In <FIG>, magnetic flux is depicted using magnetic flux lines <NUM> with arrows showing the direction of flow in the magnetic flux path. In <FIG>, external actuator <NUM> includes a single magnet <NUM> with a north pole section and a south pole section. In the single magnet example depicted in <FIG>, the external actuator <NUM> may comprise a ferromagnetic material so that the magnetic flux flows from the north pole section of magnet <NUM>, through external actuator <NUM>, through internal actuation member <NUM>, and through external actuator <NUM> to return to the south pole section of magnet <NUM>. Although a single magnet <NUM> is depicted, in various examples, multiple magnets may be included in external actuator <NUM> in the same orientation as magnet <NUM> to intensify the strength of the magnetic field and, in turn, increase the restorative torque generated when internal actuation member <NUM> becomes misaligned from external actuator <NUM> (as shown in <FIG>).

<FIG> depict a magnetic flux path through body <NUM> of a magnet-actuated valve utilizing two external magnets 406a and 406b and including a magnetically inert material <NUM> enclosed within the body <NUM> of the valve, in accordance with various aspects of the present disclosure. The example depicted in <FIG> is similar to the example depicted in <FIG> except that in <FIG>, internal actuation member <NUM> may comprise ferromagnetic material embedded within magnetically inert material <NUM>. Additionally, although two magnets are depicted in <FIG>, a different number of magnets may be used in accordance with the various techniques and embodiments described herein. Examples of magnetically inert material <NUM> may include ceramic, plastics, composites, non-<NUM> series stainless steel, molding material, rubber, etc. In the examples depicted in <FIG>, although internal actuation member <NUM> is depicted as a rectangular bar, internal actuation member <NUM> may instead by separated into a number of different portions embedded within magnetically inert material <NUM>. For example, a number of iron strips, rods, spheres, tabs, and/or other shapes of ferromagnetic materials may be embedded within magnetically inert material <NUM> to create a magnetic flux path through internal actuation member <NUM> inside body <NUM>. The various embedded ferromagnetic materials may be embedded in such a way that results in a lowest magnetic reluctance when internal actuation member <NUM> in at least one position (e.g., the position depicted in <FIG> or a position that is <NUM>° from the position depicted in <FIG>) and a higher magnetic reluctance in another position (e.g., the position depicted in <FIG>).

<FIG> depicts magnetic flux paths <NUM> through body <NUM> of another example magnet-actuated valve, in accordance with various aspects of the present disclosure. In the example depicted in <FIG>, two magnets 106a and 106b produce magnetic flux paths illustrated using flux lines <NUM>. In the example depicted in <FIG>, magnetic flux flows from the north pole section of magnet 106a through ferromagnetic external actuator 130a, through internal actuation member <NUM>, and returns to the south pole section of magnet 106a. Similarly, magnetic flux flows from the north pole section of magnet 106b through ferromagnetic external actuator 130b, through internal actuation member <NUM>, and returns to the south pole section of magnet 106a.

In various examples, actuators 130a and 130b may be a part of the same valve handle. In some examples, a valve handle or actuator may only use a single magnet, such as magnet 106a, and a single actuator (such as ferromagnetic external actuator 130a) to actuate the valve. In various other examples, more than two magnets may be used in a similar configuration to that depicted in <FIG>. For example, in the example depicted in <FIG>, four external magnets are used. Using additional magnets may produce additional torque when rotating the external magnets <NUM> and/or the external actuator <NUM>.

In various examples, the shape of internal actuation member <NUM> may be altered to produce increased torque. For example, the shape of internal actuation member <NUM> may be designed to maximize the magnetic flux density of the magnetic flux path through internal actuation member <NUM>. For example, in <FIG>, instead of the rod-shaped internal actuation member <NUM> depicted in <FIG>, the internal actuation member <NUM> depicted in <FIG> comprises a rounded surface facing away from the center of body <NUM> and toward external magnets 106a, 106b. Additionally, in the example depicted in <FIG>, the surface of internal actuation member <NUM> opposite of the rounded surface is flat. Other shapes and designs of internal actuation member <NUM> may be used in order to reach a desired magnetic flux density for a particular valve type.

<FIG> depicts another magnet-actuated valve including four U-shaped external magnets, in accordance with various aspects of the present disclosure. Similar to the example depicted in <FIG>, the embodiment shown in <FIG> includes four external, U-shaped magnets. Each of the four external U-shaped magnets creates its own magnetic flux path through body <NUM> and through internal actuation member <NUM>.

<FIG> depicts a cross-sectional side view of a magnet-actuated valve including four ferromagnetic actuation members and four sets of external magnets in accordance with various aspects of the present disclosure. Those portions of <FIG> that have been previously described with reference to <FIG> may not be described again herein for purposes of clarity and brevity. The example depicted in <FIG> displays external magnets <NUM> stacked in a vertical orientation with respect to one another. In some examples, each vertical layer of external magnets <NUM> may correspond with its own internal actuation member <NUM>. In some other examples, there may be a single internal actuation member <NUM> that is actuated by rotating external magnets <NUM> and actuators <NUM>. As described previously, using additional external magnets <NUM> may produce additional torque when rotating the external magnets <NUM> along with actuator(s) <NUM>.

<FIG> depicts a cross-sectional side view of a magnet-actuated ball valve, in accordance with some aspects of the present disclosure. Those components in <FIG> that have been described previously with reference to <FIG> may not be described again for purposes of clarity and brevity. In the magnet-actuated ball valve depicted in <FIG>, the valve member <NUM> may be a perforated ball <NUM>. Rotation of external actuator <NUM> (and thus external magnets <NUM>) may cause rotation of internal actuation member <NUM>. Rotation of internal actuation member <NUM> may actuate movement of perforated ball <NUM>. When the opening in perforated ball <NUM> is in line with the flow of material or in line with the direction of intended flow through the valve, the valve may be in an open position. When the opening in perforated ball <NUM> is not in line with the flow of material through or direction of intended flow, the valve may be in a closed position.

<FIG> depicts a cross-sectional side view of a magnet-actuated butterfly valve, in accordance with various aspects of the present disclosure. Those components in <FIG> that have been described previously with reference to <FIG> may not be described again for purposes of clarity and brevity. In the magnet-actuated butterfly valve depicted in <FIG>, the valve member <NUM> may be a plate <NUM> configured to rotate between an open and a shut configuration with the rotation of stem <NUM>. Stem <NUM> may, in turn, be coupled to and rotate with internal actuation member <NUM>. As previously discussed, internal actuation member <NUM> may rotate due to torque caused by rotation of external magnets <NUM>.

<FIG> depicts a cross-sectional side view of a worm gear <NUM> coupled to an actuation mechanism of a magnet-actuated valve, in accordance with various aspects of the present disclosure. Those components of <FIG> that have been previously discussed in reference to <FIG> may not be discussed again herein for purposes of clarity and brevity. Various valve types, such as ball valves (<FIG>) and/or butterfly valves (<FIG>), may require higher torque to actuate relative to other types of valves, such as gate valves. Accordingly, in some examples in accordance with various embodiments described herein, the actuation mechanism of a valve may include a stem <NUM> with a helical ridge (sometimes referred to as a "worm") effective to turn a worm gear <NUM>. The worm gear <NUM> may produce an increased torque when rotated relative to rotation of stem <NUM> alone. Turning worm gear <NUM> may actuate the valve member between an open and a closed position.

<FIG> depicts a cross-sectional side view of a travelling nut actuation mechanism coupled to the stem of a magnet-actuated valve, in accordance with various aspects of the present disclosure. Those components of <FIG> previously described with reference to <FIG> may not be described herein for purposes of brevity and clarity. In various valve types that require more torque to operate, a traveling nut architecture may be used to increase the torque provided by the magnetic actuation mechanism described herein. Accordingly, in some examples in accordance with various embodiments described herein, the actuation mechanism of a valve may include a stem <NUM> with a helical ridge mated to a traveling nut <NUM>. As internal actuation member <NUM> rotates, traveling nut <NUM> may move up (or down, depending on the direction of rotation) stem <NUM>. Upwards and downwards movement of traveling nut <NUM> may, in turn, rotate a lever <NUM>. The lever <NUM> may produce an increased torque when rotated relative to rotation of stem <NUM> alone. Turning lever <NUM> may actuate the valve member between an open and a closed position.

<FIG> depict a cross-sectional view of a lever-operated gate valve of a magnet-actuated valve, in accordance with various aspects of the present disclosure. Those components of <FIG> previously described with reference to <FIG> may not be described herein for purposes of brevity and clarity. <FIG> shows the lever-operated gate valve in a closed position with valve member <NUM> blocking the flow of fluid through the valve (e.g., into and out of the page in the example shown). External magnet <NUM> may be above the exterior of the cross-sectional portion of the lever-operated gate valve depicted in <FIG>. External actuator <NUM> may be rotated around a fulcrum. Rotation of external actuator <NUM> around the fulcrum may apply a magnetic force on internal actuation member <NUM>. Internal actuation member <NUM> may be coupled to valve member <NUM>.

As shown in <FIG>, when external actuator <NUM> is rotated around the fulcrum, internal actuation member <NUM> may move inside body <NUM> of the lever-operated gate valve. In turn, internal actuation member <NUM> may move valve member <NUM> between an open position and a closed position. In some examples, external actuator <NUM> may be a handle with a magnetic pole section situated both "above" the lever-actuated gate valve (e.g., out of the page), and another magnetic pole section situated "below" the lever-actuated gate valve (e.g., into the page). In such examples, the external actuator <NUM> may comprise a ferromagnetic material such that a magnetic flux path exists from the magnetic pole section above the valve, through the ferromagnetic portions of the internal actuation member <NUM>, to the magnetic pole section below the valve, and through the ferromagnetic portions of the external actuator <NUM>.

<FIG> depict a magnetic flux path through a magnet-actuated valve including an external electromagnet <NUM>, in accordance with various aspects of the present disclosure. Although in many of the previous examples, permanent external magnets are shown and described, external electromagnets may be used in various embodiments. For example, <FIG> depict a coil of wire wrapped around ferromagnetic external actuator <NUM>. Supplying an electric current to the coil of wire produces magnetic flux and forms the magnetic flux path shown in <FIG> using flux lines <NUM>. Although a single electromagnet <NUM> is shown, any number of electromagnets may be used in varying orientations in accordance with various examples. In general, when electromagnet <NUM> is powered off, the valve will maintain its current position.

<FIG> depicts a cross-sectional side view of a magnet-actuated valve including a cheater handle, in accordance with various aspects of the present disclosure. In some circumstances, it may be desirable to over-torque a valve actuator. For example, in various industries, such as the petrochemical industry, valves may often become corroded and/or stuck in a particular position, such that a normal amount of torque may be insufficient to actuate the valve. In some cases, "cheater" handles may be used to over-torque the actuation mechanism of stuck valves.

The cheater handle may comprise an actuator <NUM> for a magnet-actuated valve that may be used with various embodiments described herein. The actuator <NUM> of the cheater handle may be coupled to larger and/or more powerful external magnets <NUM> relative to external magnets <NUM> (in terms of pull force and/or magnetic field strength) described in reference to <FIG>. External actuator <NUM> may be a handle, and may further comprise a magnetically permeable material, such as a ferromagnetic material. Magnetically permeable conical portions <NUM> funnel the magnetic flux from external magnets <NUM> through internal actuation member <NUM>. The surface of magnetically permeable conical portions <NUM> that are adjacent to external magnets <NUM> may correspond in size to the size of the external magnets <NUM>. Similarly, the size of the surface of magnetically permeable conical portions <NUM> that are adjacent to internal actuation member <NUM> may correspond in size to the adjacent surface of internal actuation member <NUM>. Magnetically permeable cones <NUM> may be disposed between the external magnets <NUM> and the portions of the body <NUM> adjacent to internal actuation member <NUM>. The amount of torque applied to internal actuation member <NUM> when rotating cheater handle <NUM> and external magnets <NUM> may be larger relative to the amount of torque applied to internal actuation member <NUM> when rotating external actuator <NUM> and external magnets 106a, 106b, depicted in <FIG>. Accordingly, in some cases cheater handle <NUM> may be used to "break" stuck valves so that the valves may be actuated between a closed and open position (or vice versa).

Among other potential benefits, valves in accordance with embodiments of the present disclosure create a magnetic flux circuit through a magnetically asymmetric core of a sealed valve. A ferromagnetic actuation member sealed inside the valve forms a magnetically conductive path in certain orientations. The ferromagnetic actuation member can be oblong in shape or have different permeability in different directions by, for example, being comprised of different materials of different magnetic permeability. Torque may be transmitted from external magnets to the ferromagnetic actuation member. Actuation of the internal member may in turn drive the stem of the valve and may actuate the valve member between an open and a closed position or between a closed and an open position, depending on the direction in which the valve is actuated. The ferromagnetic actuation member has preferred orientations with respect to the external magnets. If the ferromagnetic actuation member is oriented in a position other than the preferred orientation while in the magnetic fields created by the external magnets, the ferromagnetic actuation member will experience a restorative torque, pulling the ferromagnetic actuation member back into the preferred orientation.

The use of external magnets, which may be part of a valve handle or otherwise coupled to an external actuator of a valve, allows the external magnets to be insulated and/or cooled if the valve is to be operated in temperatures exceeding the rated operating temperatures of the external magnets. Additionally, the external magnets may be removed when the valve is constructed and/or serviced in temperatures exceeding the Curie temperatures of the external magnets. Many common commercial magnets, such as Neodymium magnets have relatively low recommended operating temperatures and Curie temperatures. Valves designed in accordance with embodiments of the present disclosure may use such magnets since the magnets may be insulated, cooled, and/or removed prior to the valve reaching temperatures in excess of the Neodymium magnet's recommended operating and/or Curie temperatures. Additionally, valves in accordance with embodiments of the present disclosure may not require a stem seal where the stem extrudes from the body of the valve. Accordingly, stem seal leaks, which are a significant issue with many traditional valves, may be avoided. Generally, while the embodiments depicted in the figures show examples using a certain number of external magnets, different numbers of magnets, apart from what is shown, may be used in accordance with the techniques and valve architectures described herein. For example, while the example magnets in <FIG> depict two external magnets 406a and 406b, a single external magnet may be used instead. Similarly, three or more external magnets may be used in accordance with the present disclosure. The type and/or number of external magnets used in various valve configurations may be chosen based on a desired amount of torque, based on design and manufacturing costs, and/or based on other concerns specific to a particular application. Therefore, the number of magnets shown in the various figures is not meant to be taken in a limiting sense and other, different numbers of external magnets are explicitly contemplated herein.

While the invention has been described in terms of particular embodiments and illustrative figures, those of ordinary skill in the art will recognize that the invention is not limited to the embodiments or figures described.

Claim 1:
A valve (<NUM>) comprising:
a valve body (<NUM>) having an interior portion and an exterior portion, the interior portion defining a cavity (<NUM>);
a movable valve member (<NUM>, <NUM>, <NUM>) movable between an open position and a closed position;
an internal actuation member (<NUM>) having a ferromagnetic portion comprising an impermanent magnet disposed in the cavity, the internal actuation member operatively coupled to the movable valve member such that movement of the internal actuation member actuates movement of the movable valve member between the open position and the closed position;
an external actuator (<NUM>) coupled to the exterior portion of the valve body, the external actuator comprising:
a first magnetic pole section adjacent to the exterior portion of the valve body;
a second magnetic pole section adjacent to the exterior portion of the valve body,
wherein magnetic flux (<NUM>, <NUM>, <NUM>) flows from the first magnetic pole section through the ferromagnetic portion to the second magnetic pole section in a magnetic flux path through the interior portion of the valve to magnetize the impermanent magnet, the magnetic flux having a magnitude sufficient to cause movement of the internal actuation member in response to movement of the external actuator when it rotates around the valve body, and
a ferromagnetic material completing a return flow path for the magnetic flux between the first magnetic pole section and the second magnetic pole section.