Patent Description:
Actuators automate control valves by providing a force and/or torque that causes motion and/or rotation to open or close a valve. In operation, a controller may cause an actuator to position a flow control member of a valve to a desired position to regulate fluid flowing through the valve. Hydraulic override pumps can be used in process control systems to override automatic control of valves or other devices in the process control system. During emergency situations, power failures, or if air supply to a pneumatic actuator is shut down, for example, it may be necessary to manually override the position of a flow control member of a valve to a predetermined position. A human operator can operate a hydraulic override pump to manually pump fluid into the actuator, thereby controlling the state of the valve (e.g., closing the valve).

Document <CIT> discloses a rotary valve (<NUM>) that includes a valve housing (<NUM>) with a plurality of ports, and a rotor valve body (<NUM>) accommodated in an accommodating portion (<NUM>) in the valve housing (<NUM>). The rotary valve (<NUM>) has a pump (P) connected to a supply port (10P), a return port (<NUM>), a first port (10A) connected to a first chamber (<NUM>) of a cylinder (<NUM>), and a second port (10B) connected to a second chamber (<NUM>) of the cylinder (<NUM>). The rotor valve body (<NUM>) consists of a rotating part (12A) and a valve part (12B) with two annular valve grooves (12C). When the rotor valve body (<NUM>) is in the position shown in <FIG>, the supply port (10P) is closed by the rotor valve body (<NUM>), so that no pressure is supplied to the first and second chambers (<NUM>, <NUM>). The rotor valve body (<NUM>) can be rotated to the position in <FIG> so that hydraulic pressure supplied by the pump (P) passes through supply port (10P) to the first port (10A), and the second port (10B) is connected to the return port (10T), or to the position in <FIG>, in which hydraulic pressure supplied by the pump (P) passes through the supply port (10P) to the second port (10B), and the first port (10A) is connected to the return port (10T). <CIT> does not disclose a rotor having a sealing surface with a first pair of openings connected by a first passageway formed in the rotor, a second pair of openings connected by a second passageway formed in the rotor, and a third pair of openings connected by a third passageway formed in the rotor; furthermore, the rotor does not comprise a neutral position in which the first actuator port and the second actuator port are fluidly coupled via the cavity in which the rotor is disposed, and the third passageway fluidly couples the pump port and the reservoir port.

Document <CIT> discloses a hydraulic leveling system used to level a working platform of an aerial work equipment. The system includes a leveling cylinder (<NUM>), a hydraulic pump (<NUM>) for transmitting power, and an electromagnetic reversing valve (<NUM>). D2 mentions that the system also includes an emergency manual leveling device with a manual reversing valve (<NUM>). D2 mentions that the manual reversing valve (<NUM>) is operable in a first working position and a second working position.

Document <CIT> discloses a modular actuator and hydraulic valve assembly for blow-out preventers (<NUM>). Each assembly (<NUM>) includes a hydraulic valve assembly (<NUM>) consisting of a hydraulic valve (<NUM>) to which is mounted an integrated double-action pneumatic actuator (<NUM>). D3 mentions a valve rotor (<NUM>).

An apparatus disclosed herein is according to annexed independent claim <NUM>. Other advantageous features are defined in the annexed dependent claims.

The figures are not to scale. Instead, the thickness of the layers or regions may be enlarged in the drawings. In general, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. As used in this patent, stating that any part (e.g., a layer, film, area, region, or plate) is in any way on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, indicates that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. Stating that any part is in "contact" with another part means that there is no intermediate part between the two parts. Although the figures show layers and regions with clean lines and boundaries, some or all of these lines and/or boundaries may be idealized. In reality, the boundaries and/or lines may be unobservable, blended, and/or irregular.

Actuators are commonly used in process control systems to automate control of certain devices or components of the process control system. For example, actuators are commonly used to automate control valves by providing a force and/or torque that may cause linear and/or rotary motion to open or close a valve. In operation, a controller may cause the actuator to position a flow control member of the valve in a desired position to regulate fluid flowing through the valve. During emergency situations, power failures, and/or if air/hydraulic supply to the actuator is shut down, for example, it may be necessary to manually override the position of the flow control member of the valve to a desired position (e.g., a closed position). Therefore, many actuators include a manual hydraulic override pump that permits a human operator to manually pump hydraulic fluid into or away from the actuator and thereby cause the flow control member to move to the desired position. These manual hydraulic override pumps do not require an outside power source. Instead, known manual hydraulic override pumps include hand pumps and selector valves to direct the pumping fluid to one chamber or another chamber of the actuator.

Known hydraulic override pumps utilize a selector valve having a plunger that is moved in a linear direction to connect the hand pump to one of the chambers of the actuator. However, this type of selector valve requires a relatively large amount of space to accommodate the movement of the plunger. Thus, known hydraulic override pumps are relatively large in size. Further, this type of linear plunger selector valve utilizes rubber seals that tend to wear and degrade over time, which results in leakage and inefficient pumping operation.

Disclosed herein are example apparatus, methods, and articles of manufacture that that address the drawbacks noted above. Example manual hydraulic override pumps are disclosed herein that include a selector valve (which may also be referred to as a flow control valve) having a rotor that is rotatable in a cavity of a manifold. The rotor is rotatable within the cavity to connect various ports on the manifold. The example manual hydraulic override pump can be implemented in connection with an actuator that is used to control a position of a flow control member of a valve. If a controller and/or pump associated with the actuator fails, for example, the example manual hydraulic override pump can be used to manually operate the actuator and thereby move the flow control member (e.g., to open the valve, to close the valve, to partially open the valve, etc.).

In some examples, the manual hydraulic override pump includes a handwheel that is coupled to the rotor by a shaft. A human operator can rotate the handwheel, thereby rotating the rotor in the cavity. The rotor includes a sealing surface that is engaged with and slides along a disk in the manifold. The disk has openings that align with passageways in the manifold connected to different ports. In particular, the manifold has a pump port that is fluidly coupled to a pump, such as a hand pump, a reservoir port that is fluidly coupled to a reservoir of hydraulic fluid, a first actuating port that is fluidly coupled to a first chamber of the actuator, and a second actuating port that is fluidly coupled to a second chamber of the actuator. The rotor has pairs of openings in the sealing surface that are connected by respective passageways in the rotor. The rotor can be rotated (via the handwheel) to align different pairs of the openings with different openings in the disk, thereby fluidly connecting various ones of the ports. In some examples, the rotor and the disk are constructed of metal, such as tungsten carbide. The metal-to-metal contact between the rotor and the disk provides excellent sealing performance. Further, unlike known selector valves that use rubber seals that tend to wear, the example metal-to-metal sealing interface exhibits minimal (if any) wear and, thus, provides increased lifespan.

In some examples, the example rotor can be rotated (via the handwheel) between three positions including a neutral position, a first actuating position, and a second actuating position. In the neutral position, the hand pump is fluidly coupled to the reservoir, such that any pumping of the hand pump has no effect. Further, the first and second chambers of the actuator are fluidly coupled and pressure in the first and second chambers is equalized. Thus, during normal operation of the actuator, the rotor is left in the neutral position. If the actuator becomes inoperable and a human operator desires to move the flow control member of the valve in a first direction, the operator may turn the handwheel (e.g., <NUM>° to the left from the neutral position) to rotate the rotor to the first actuating position. In the first actuating position, the rotor fluidly connects various passageways in the manifold such that the hand pump is fluidly coupled to the first chamber of the actuator, and the reservoir is fluidly coupled to the second chamber of the actuator. The hand pump can then be used to pump hydraulic fluid into the first chamber of the actuator to move the flow control member in a first direction (e.g., to close the valve). If the human operator desires to move the flow control member in the opposite direction, the human operator can turn the handwheel (e.g., <NUM>° to the right from the neutral position) to rotate the rotor to the second actuating position. In the second actuating position, the rotor fluidly connects various passageways in the manifold such that the hand pump is fluidly coupled to the second chamber of the actuator, and the reservoir is fluidly coupled to the first chamber of the actuator. The hand pump can then be used to pump hydraulic fluid into the second chamber of the actuator to move the flow control member in a second direction opposite the first direction (e.g., to open the valve).

The use and arrangement of the rotor in the manifold results in a smaller, more compact override pump. As such, example override pumps disclosed herein can be utilized in more applications or environments than known override pumps that require a larger amount of space. Further, the use of the rotor greatly reduces the number of parts or components, which reduces assembly time and manufacturing costs associated with the override pump.

Also disclosed herein is an example reset cylinder that can be actuated (e.g., via a command signal from a control room) to move the handwheel (and, thus, the rotor) back to the neutral position. Thus, it is not required for a human operator to manually switch the selector valve back to the neutral position.

Turning to the figures, <FIG> is a schematic illustration of an example hydraulic override pump <NUM> constructed in accordance with the teaching of this disclosure. In <FIG>, the example hydraulic override pump <NUM> is shown in connection with an example actuator <NUM> that is used to control a valve <NUM>. In particular, the actuator <NUM> is used to control a position of a flow control member <NUM> of the valve <NUM>, thereby affecting the flow of fluid through the valve <NUM>. The example manual hydraulic override pump <NUM> may be used to manually actuate the actuator <NUM> to control the position of the flow control member <NUM>, as disclosed in further detail herein.

In this example, the actuator <NUM> has a stem or shaft <NUM> that is coupled (e.g., directly, via a valve stem or shaft, etc.) to the flow control member <NUM> of the valve <NUM>. The shaft <NUM> is coupled to a piston <NUM> in the actuator <NUM>. In the illustrated example, a valve controller <NUM>, such as a positioner, for example, is shown. In the illustrated example, the valve controller <NUM> controls the operation of a pump <NUM> (e.g., via a control signal from a control room) to supply pressurized hydraulic fluid to the actuator <NUM> to move the piston <NUM>, thereby moving the flow control member <NUM> of the valve <NUM> to a desired position. In other examples, the valve controller <NUM> may alternatively control the flow of instrument air (rather than hydraulic fluid) to the actuator <NUM> to move the piston <NUM> in a similar manner. In the illustrated example, the actuator <NUM> includes a return spring <NUM> to bias the piston <NUM> against the force of the fluid operating on the opposite side of the piston <NUM>. The valve controller <NUM> may release pressure from the actuator <NUM> to enable the piston <NUM> (and, thus, the flow control member <NUM>) to be moved by the spring <NUM> to the actuator's failure position (i.e., the position of the actuator <NUM> absent an outside force supplied by a pressurized fluid). In other examples, the actuator <NUM> may not include a return spring.

In some instances, the pump <NUM>, the controller <NUM>, or a related component such as an instrument air supply may become inoperable (e.g., due to a failed part, due to a power outage, etc.). In such a situation, the hydraulic manual override pump <NUM> may be used to manually pump fluid into the actuator <NUM> to move the flow control member <NUM> and control the state of the valve <NUM>. In the illustrated example, the actuator <NUM> includes a hydraulic override cylinder <NUM> that is operated by the manual hydraulic override pump <NUM>. In this example, the hydraulic override cylinder <NUM> is a double-acting actuator having a first chamber <NUM> (e.g., a first cylinder) and a second chamber <NUM> (e.g., a second cylinder) separated by a piston <NUM> (which may be referred to as a driver). A stem <NUM> is coupled to the piston <NUM> of the hydraulic override cylinder <NUM>. When the first chamber <NUM> is pressurized and the piston <NUM> moves to the left in <FIG>, the stem <NUM> moves to the left and enables the piston <NUM> of the actuator <NUM> and, thus, the flow control member <NUM> of the valve <NUM>, to move under normal operation based on the balance of forces operating on each side of the piston <NUM> (e.g., in a first direction, to the left in <FIG>). When the second chamber <NUM> is pressurized and the piston <NUM> moves to the right in <FIG>, the stem <NUM> moves the piston <NUM> of the actuator <NUM> to the right in <FIG> and, thus, moves the flow control member <NUM> of the valve <NUM> away from the failure position (e.g., in a second direction). In this manner, the manual hydraulic override pump <NUM> can be used to override the actuator <NUM> and control the flow control member <NUM>. While in the illustrated example the actuator <NUM> is a linear actuator, the manual hydraulic override pump <NUM> and hydraulic override cylinder <NUM> can similarly be used in connection with a rotary actuator that rotates a flow control member of a valve (e.g., a butterfly valve). In such an example, the first and second directions of the shaft <NUM> may be rotating in a clockwise and counter-clockwise directions.

In the illustrated example, the manual hydraulic override pump <NUM> includes a pump <NUM>, a reservoir <NUM> containing hydraulic fluid (e.g., oil), and a manifold <NUM> with a selector valve <NUM>. In this example, the pump <NUM> is a hand pump, referred to herein as the hand pump <NUM>. The manifold <NUM> has fluid lines, flow paths, or passageways that connect to the hand pump <NUM>, the reservoir <NUM>, the first chamber <NUM>, and the second chamber <NUM>. The selector valve <NUM> may be operated to connect various ones of the fluid lines to form flow paths between certain ones of the hand pump <NUM>, the reservoir <NUM>, the first chamber <NUM>, and the second chamber <NUM>.

In the illustrated example, the example manifold <NUM> has a first actuator port <NUM> that is to be fluidly coupled to the first chamber <NUM> of the actuator <NUM>, a second actuator port <NUM> that is to be fluidly coupled to the second chamber <NUM> of the actuator <NUM>, a pump port <NUM> that is to be fluidly coupled to the hand pump <NUM>, and a reservoir port <NUM> that is to be fluidly coupled to the reservoir <NUM>. In this example, the first actuator port <NUM> is fluidly coupled to the first chamber <NUM> via a fluid line <NUM> (e.g., a first fluid line), the second actuator port <NUM> is fluidly coupled to the second chamber <NUM> via a fluid line <NUM> (e.g., a second fluid line), the pump port <NUM> is fluidly coupled to the hand pump <NUM> via a fluid line <NUM> (e.g., a third fluid line), and the reservoir port <NUM> is fluidly coupled to the reservoir <NUM> via a fluid line <NUM> (e.g., a fourth fluid line). While in the illustrated example the hand pump <NUM>, the reservoir <NUM>, and the actuator <NUM> are fluidly coupled to the manifold <NUM> via fluid lines, in other examples, the hand pump <NUM>, the reservoir, and/or the actuator <NUM> may be directly coupled to the manifold <NUM> such that no fluid lines are used.

In the illustrated example, the manifold <NUM> includes a fluid line <NUM> that fluidly couples the first actuator port <NUM> and the selector valve <NUM>. A first check valve and orifice <NUM> are disposed in the fluid line <NUM> to control the flow of fluid through the fluid line <NUM>. Similarly, the manifold <NUM> includes a fluid line <NUM> that fluidly couples the second actuator port <NUM> and the selector valve <NUM>, and a second check valve and orifice <NUM> are disposed in the fluid line <NUM> to control the flow of fluid through the fluid line <NUM>.

In the illustrated example, the manifold <NUM> includes a fluid line <NUM> that fluidly couples the pump port <NUM> and the selector valve <NUM>. A first check valve <NUM> is disposed in the fluid line <NUM>. The manifold also includes a fluid line <NUM> that fluidly couples the reservoir port <NUM> and the selector valve <NUM>. The fluid line <NUM> branches off and is fluidly coupled to the pump port <NUM>. A second check valve <NUM> is disposed in the fluid line <NUM>. When the hand pump <NUM> is operated, fluid from the reservoir <NUM> flows through the second check valve <NUM> and into the hand pump <NUM>, and then the fluid is pushed through the first check valve <NUM> to the selector valve <NUM>.

In the illustrated example, the manifold <NUM> includes a pressure relief valve <NUM> disposed in a fluid line <NUM> between the fluid line <NUM> and the fluid line <NUM> to relieve excess pressure. Further, a third check valve <NUM> is disposed between the fluid line <NUM> and the fluid line <NUM>, which enables instant higher pressure in the fluid line <NUM> (from the reservoir <NUM>) to be released to ensure the safety of the reservoir <NUM>.

In the illustrated example, the selector valve <NUM> is operable between three positions or states including a neutral position <NUM>, a first actuating position <NUM>, and a second actuating position <NUM>. These positions correspond to a position of a rotor <NUM> (<FIG>) of the selector valve <NUM> disclosed in further detail herein. In the neutral position <NUM>, which is the position shown in <FIG>, the selector valve <NUM> fluidly couples the fluid lines <NUM>, <NUM>, <NUM>, <NUM>. As such, the first and second chambers <NUM>, <NUM> are fluidly connected, which enables the pressures in the first and second chambers <NUM>, <NUM> to equalize. Further, because the fluid lines <NUM> and <NUM> are fluidly connected, any pumping of the hand pump <NUM> causes hydraulic fluid to cycle around through the hand pump <NUM> and, thus, has no effect on either of the first or second chambers <NUM>, <NUM>.

In the first actuating position <NUM>, the selector valve <NUM> fluidly couples the fluid line <NUM> and the fluid line <NUM> and, thus, fluidly couples the pump port <NUM> and the first actuator port <NUM>. Then, when the hand pump <NUM> is activated (e.g., via a human operator), hydraulic fluid is supplied to (e.g., pumped into) the first chamber <NUM> of hydraulic override cylinder <NUM>, thereby enabling (e.g., via return force from the return spring <NUM>) the piston <NUM> and the shaft <NUM> to move to the left in <FIG> and, thus, moving the flow control member <NUM>. Further, in the first actuating position <NUM>, the selector valve <NUM> fluidly couples the fluid line <NUM> and the fluid line <NUM> and, thus, fluidly couples the reservoir port <NUM> and the second actuator port <NUM>. As a result, hydraulic fluid in the second chamber <NUM> is pushed back to the reservoir <NUM> as the piston <NUM> moves to the left in <FIG>.

In the second actuating position <NUM>, the selector valve <NUM> fluidly couples the fluid line <NUM> and the fluid line <NUM> and, thus, fluidly couples the pump port <NUM> and the second actuator port <NUM>. Then, when the hand pump <NUM> is activated (e.g., via a human operator), hydraulic fluid is supplied to (e.g., pumped into) the second chamber <NUM> of the hydraulic override cylinder <NUM>, thereby causing the piston <NUM> and the shaft <NUM> to move to the right in <FIG> and, thus, moving the flow control member <NUM>. Further, in the second actuating position <NUM>, the selector valve <NUM> fluidly couples the fluid line <NUM> and the fluid line <NUM> and, thus, fluidly couples the reservoir port <NUM> and the first actuator port <NUM>. As a result, hydraulic fluid in the first chamber <NUM> is pushed back to the reservoir <NUM> as the piston <NUM> is moved to the right in <FIG>.

While in the illustrated example the actuator <NUM> is a single-acting actuator, in other examples, the actuator <NUM> may be implemented as double-acting actuator without a return spring. In such an example, the shaft <NUM> of the hydraulic override cylinder <NUM> may be coupled (directly or indirectly) to the shaft <NUM> of the actuator <NUM> to move the shaft <NUM> in one direction or the other. Further, while in the illustrated example, the hydraulic override cylinder <NUM> is a double-acting actuator, in other examples, the hydraulic override cylinder <NUM> may be implemented as a single-acting actuator with a return spring. In such an example, only one of the first actuating port <NUM> or the second actuator port <NUM> is fluidly coupled to the hydraulic override cylinder <NUM>. In one actuating position, pressure can be applied to the hydraulic override cylinder <NUM>. In the other actuating position, pressure can be relieved from the hydraulic override cylinder <NUM>. In another example, single-acting cylinders can be disposed on opposite sides of a double-acting main actuator (e.g., an actuator with no return spring). In such an example, the first actuating position <NUM> would cause the shaft of the double-acting main actuator to move in one direction, and the second actuating position <NUM> would cause the shaft of the double-acting actuator to move in the opposite direction.

<FIG> illustrate an example physical implementation of the example manual hydraulic override pump <NUM>. The actuator <NUM>, the valve <NUM>, and the fluid lines <NUM>, <NUM> of <FIG> are not shown.

As shown in <FIG>, the manual hydraulic override pump <NUM> includes the hand pump <NUM>, the reservoir <NUM>, and the manifold <NUM>. The reservoir <NUM> is fluidly coupled to the manifold <NUM> via the fluid line <NUM>. In the illustrated example, the hand pump <NUM> includes a pump cylinder <NUM> and a pump rod <NUM>. The pump rod <NUM> is movable within the pump cylinder <NUM> to pull fluid into or push fluid out of a chamber in the pump cylinder <NUM>. As the pump rod <NUM> moves up (out from the pump cylinder <NUM>), backpressure is created in the chamber of the pump cylinder <NUM>, and fluid is pulled from the reservoir <NUM> into the chamber of the pump cylinder <NUM>. When the pump rod <NUM> moves back into the chamber of the pump cylinder <NUM>, the fluid is forced out of the chamber of the pump cylinder <NUM> and toward the selector valve <NUM> (<FIG>) in the manifold <NUM>.

In the illustrated example, the hand pump <NUM> includes a lever <NUM> that rotates to move the pump rod <NUM> within the pump cylinder <NUM>. In the illustrated example, the pump rod <NUM> is rotatably coupled to the lever <NUM> at a first joint <NUM>. Further, as shown in <FIG>, the lever <NUM> is rotatably coupled to an example support <NUM> at a second joint <NUM>. In the illustrated example, the support <NUM> is coupled to the manifold <NUM>. In the illustrated example, an end of the lever <NUM> has a pump handle <NUM> to be grasped by a human operator. During operation, the human operator moves the lever <NUM> up and down (as shown by the arrows) to pump fluid. In this example, the hand pump <NUM> is entirely a manual pump. In other words, the hand pump <NUM> is not activated or actuated via an automatic system.

In some examples, the manual hydraulic override pump <NUM> includes an example extension bar <NUM>. In <FIG>, the extension bar <NUM> is shown as coupled (via clips) to the reservoir <NUM>. The extension bar <NUM> can be detached from the reservoir <NUM> and attached to the pump handle <NUM> of the lever <NUM> (e.g., slid onto the pump handle <NUM>). The extension bar <NUM> can then be used to the move the lever <NUM> up and down. The extension bar <NUM> increases the length of the lever arm and, thus, increases the input force that a human operator can exert on the pump rod <NUM>.

As disclosed above, the manual hydraulic override pump <NUM> includes the selector valve <NUM> (<FIG>) to connect the various ports on the manifold <NUM>. To control the position or state of the selector valve <NUM>, the manual hydraulic override pump <NUM> includes a handwheel <NUM>. The handwheel <NUM> can be rotated or turned by a human operator to select the desired position or state of the selector valve <NUM>. The handwheel <NUM> is rotatable between a neutral position (corresponding to the neutral position <NUM> of the selector valve <NUM> (<FIG>)), a first actuating position (corresponding to the first actuating position <NUM> of the selector valve <NUM> (<FIG>)), and a second actuating position (corresponding to the second actuating position <NUM> of the selector valve <NUM> (<FIG>)). In this example, the neutral position is between the first and second actuating positions.

In <FIG>, the handwheel <NUM> is shown in the neutral position. In the neutral position, the selector valve <NUM> (<FIG>) fluidly couples the hand pump <NUM>, the reservoir <NUM>, the first chamber <NUM> (<FIG>), and the second chamber <NUM> (<FIG>). As such, the pressures in the first and second chambers <NUM>, <NUM> (<FIG>) are equalized, and pumping the hand pump <NUM> has no effect on the actuator <NUM> (<FIG>).

To move the handwheel <NUM> to the first actuating position, the handwheel <NUM> can be rotated counter-clockwise to a first position (e.g., <NUM>° to the left). In the first actuating position, the selector valve <NUM> (<FIG>) fluidly couples the hand pump <NUM> and the first chamber <NUM> (<FIG>) of the actuator <NUM> (<FIG>), and the selector valve <NUM> fluidly couples the reservoir <NUM> and the second cylinder <NUM> (<FIG>) of the actuator <NUM>. Then, when the lever <NUM> of the hand pump <NUM> is moved up and down, hydraulic fluid is pumped from the reservoir <NUM>, through the selector valve <NUM>, and into the first chamber <NUM> of the actuator <NUM> to move the shaft <NUM> (<FIG>) of the actuator <NUM> and/or otherwise enable the shaft <NUM> of the actuator <NUM> to move (e.g., via the return spring <NUM>) in a first direction. Fluid from the second chamber <NUM> of the actuator <NUM> is pushed out of the second chamber <NUM> back to the reservoir <NUM>.

To move the handwheel <NUM> to the second actuating position, the handwheel <NUM> can be rotated clockwise to a second position (e.g., <NUM>° to the right). In the second actuating position, the selector valve <NUM> (<FIG>) fluidly couples the hand pump <NUM> and the second chamber <NUM> (<FIG>) of the actuator <NUM> (<FIG>), and the selector valve <NUM> fluidly couples the reservoir <NUM> and the first chamber <NUM> (<FIG>) of the actuator <NUM>. Then, when the lever <NUM> of the hand pump <NUM> is moved up and down, hydraulic fluid is pumped from the reservoir <NUM>, through the selector valve <NUM>, and into the second chamber <NUM> of the actuator <NUM> to move the shaft <NUM> (<FIG>) of the actuator <NUM> and/or otherwise enable the shaft <NUM> of the actuator <NUM> to move in a second direction opposite the first direction. Further, fluid from the first chamber <NUM> is pushed out of the first chamber <NUM> back to the reservoir <NUM>. In some examples, a small resistance is applied to the handwheel <NUM> at each of the three positions to indicate to the human operator when a particular position is reached. An example detent pin that may be used to create such resistance is described in further detail in conjunction with <FIG>.

In the illustrated example of <FIG>, the manual hydraulic override pump <NUM> includes a tab <NUM> that is coupled and extends outward (e.g., downward) from the handwheel <NUM>. The tab <NUM> can be used to visually indicate the position of the handwheel <NUM> (and, thus, the selector valve <NUM>) to a human operator. As shown in <FIG>, first indicia <NUM> (e.g., "MANUAL CCW") and second indicia <NUM> (e.g., "MANUAL CW") are provided on a plate <NUM>. In the neutral position, the tab <NUM> points downward between the first and second indicia <NUM>, <NUM>. When the handwheel <NUM> is rotated counter-clockwise to the first actuating position, the tab <NUM> points to the first indicia <NUM>. When the handwheel <NUM> is rotated clockwise to the second actuating position, the tab <NUM> points to the second indicia <NUM>.

In the illustrated example, the manual hydraulic override pump <NUM> includes a pneumatic reset cylinder <NUM> (e.g., an actuator) to move the handwheel <NUM> back to the neutral position, which is disclosed in further detail herein.

<FIG> is a front, top perspective view of the example manifold <NUM>, <FIG> is a rear, bottom perspective view of the example manifold <NUM>, and <FIG> is a rear view of the manifold <NUM>. The other parts of the manual hydraulic override pump <NUM> have been removed for clarity. As shown in <FIG>, the manifold <NUM> has a front side <NUM>, a rear side <NUM> opposite the front side <NUM>, a right side <NUM>, a left side <NUM> opposite the right side <NUM>, a bottom side <NUM>, and a top side <NUM> opposite the bottom side <NUM>. These terms are used only for differentiating the various sides of the manifold <NUM>. These terms do not require a certain orientation of the example manifold <NUM>.

As shown in the illustrated example of <FIG>, the top side <NUM> of the manifold <NUM> includes a notch <NUM> to receive a bottom of the pump cylinder <NUM> (<FIG>). The pump port <NUM> is formed in the notch <NUM>. The bottom of the pump cylinder <NUM> (<FIG>) is coupled to the manifold <NUM> via a pin that extends into the pump port <NUM>, shown in further detail in connection with <FIG>. The pin includes a passageway to transfer fluid between the pump port <NUM> and the chamber in the pump cylinder <NUM>. Thus, the pin forms the fluid line <NUM> (<FIG>). In some examples, the pump cylinder <NUM> is pivotable about the pin.

As shown in <FIG>, the first actuating port <NUM> is formed in the top side <NUM> of the manifold <NUM>. The first actuating port <NUM> is to be fluidly coupled (e.g., via the fluid line <NUM> (<FIG>)) to the first chamber <NUM> of the actuator <NUM> (<FIG>). As shown in <FIG>, the second actuating port <NUM> of the illustrated example is formed in the left side <NUM> of the manifold <NUM>. The second actuating port <NUM> is to be fluidly coupled (e.g., via the fluid line <NUM> (<FIG>)) to the second chamber <NUM> of the actuator <NUM> (<FIG>). The reservoir port <NUM> of the illustrated example is formed on the left side <NUM> of the manifold <NUM>. The reservoir port <NUM> is to be fluidly coupled (e.g., via the fluid line <NUM> (<FIG>)) to the reservoir <NUM> (<FIG>). The front side <NUM> of the manifold <NUM>, as shown in <FIG>, includes an opening <NUM> to receive a shaft (shown in <FIG>) that couples the handwheel <NUM> (<FIG>) to a rotor in the manifold <NUM>.

The manifold <NUM> includes a plurality of openings in which the check valves and/or orifices can be inserted. For example, as shown in <FIG>, an opening <NUM> is formed in the front side <NUM> of the manifold <NUM> to receive the first check valve and orifice <NUM> (<FIG>). When the first check valve and orifice <NUM> is/are inserted into the opening <NUM>, the first check valve and orifice <NUM> is/are disposed in the fluid line <NUM> (<FIG>) between the selector valve <NUM> (<FIG>) and the first actuating port <NUM>. Another opening <NUM> is formed in the front side <NUM> of the manifold <NUM> to receive the second check valve and orifice <NUM> (<FIG>). When the second check valve and orifice <NUM> is/are inserted into the opening <NUM>, the second check valve and orifice <NUM> is/are disposed in the fluid line <NUM> (<FIG>) between the selector valve <NUM> (<FIG>) and the second actuating port <NUM>. An opening <NUM> is formed in the front side <NUM> of the manifold <NUM> to receive the first check valve <NUM> (<FIG>). When the first check valve <NUM> is inserted into the opening <NUM>, the first check valve <NUM> is disposed in the fluid line <NUM> (<FIG>) between the pump port <NUM> and the selector valve <NUM> (<FIG>). An opening <NUM> is formed in the right side <NUM> of the manifold <NUM> to receive the second check valve <NUM> (<FIG>). When the second check valve <NUM> is inserted into the opening <NUM>, the second check valve <NUM> is disposed in the fluid line <NUM> (<FIG>) between the reservoir port <NUM>, the selector valve <NUM> (<FIG>), and the pump port <NUM>. Another opening <NUM> is formed in the front side <NUM> of the manifold <NUM> to receive the third check valve <NUM> (<FIG>). When the third check valve <NUM> is inserted into the opening <NUM>, the third check valve <NUM> is disposed between the fluid line <NUM> and the fluid line <NUM>. As shown in <FIG>, an opening <NUM> is formed in the bottom side <NUM> of the manifold <NUM> to receive the pressure relief valve <NUM> (<FIG>). In other examples, any of the ports <NUM>, <NUM>, <NUM>, <NUM> and/or any of the openings <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> can be formed in other sides of the manifold <NUM>.

As shown in <FIG>, a bore <NUM> is formed in the rear side <NUM> of the manifold <NUM>. A block or plug is to be inserted into the bore <NUM> to define a cavity within the manifold <NUM>. As disclosed in further detail herein, a rotor and a disk are disposed in the cavity. The rotor, the disk, and the cavity form the selector valve <NUM>, which is implemented as a rotary valve. A wall <NUM> defining the bore <NUM> includes a plurality of openings. As shown more clearly in <FIG>, the wall <NUM> has four openings including a first opening <NUM> that is fluidly coupled to the fluid line <NUM> (<FIG>) that connects to the first actuating port <NUM>, a second opening <NUM> that is fluidly coupled to the fluid line <NUM> that connects to the second actuating port <NUM>, a third opening <NUM> that is fluidly coupled to the fluid line <NUM> that connects to pump port <NUM>, and a fourth opening <NUM> that is fluidly coupled to the fluid line <NUM> that connects to the reservoir port <NUM>. As disclosed in further detail herein, the rotor connects various ones of the openings to form flow paths between the first actuating port <NUM>, the second actuating port <NUM>, the pump port <NUM>, and the reservoir port <NUM>.

<FIG> is a cross-sectional view of the manual hydraulic override pump <NUM> taken along line A-A of <FIG>. As shown in <FIG>, a block <NUM> is disposed in the bore <NUM>, which defines a cavity <NUM> within the manifold <NUM>. In the illustrated example, the manual hydraulic override pump <NUM> includes a rotor <NUM> that is disposed in the cavity <NUM> of the manifold <NUM>. The rotor <NUM> is rotatable in the cavity <NUM> to fluidly connect various ones of the fluid lines and ports, as disclosed in further detail herein. The manual hydraulic override pump <NUM> includes a shaft <NUM> that is coupled to and extends from the rotor <NUM>. The shaft <NUM> extends through the opening <NUM> in the manifold <NUM>. The handwheel <NUM> is fixedly coupled to the shaft <NUM> (e.g., via a screw or bolt). Thus, rotation of the handwheel <NUM> causes rotation of the rotor <NUM> in the cavity <NUM>.

In the illustrated example, the manual hydraulic override pump <NUM> includes a disk <NUM>. The disk <NUM> is disposed in the cavity <NUM> and fixedly coupled to the wall <NUM> of the cavity <NUM>. The disk <NUM> forms a sealing interface between the rotor <NUM> and the wall <NUM>. As shown in further detail herein, the disk <NUM> includes openings that are aligned with the openings <NUM>-<NUM> (<FIG>) in the wall <NUM>. The rotor <NUM> is engaged with the disk <NUM> and is rotatable to fluidly couple certain ones of the openings <NUM>-<NUM>. The cavity <NUM>, the rotor <NUM>, and the disk <NUM> form the selector valve <NUM>, which, in this example, is a rotary valve.

Also shown in <FIG> is the pumping cylinder <NUM> of the hand pump <NUM>. The pumping cylinder <NUM> has a piston <NUM> disposed in a chamber <NUM> in the pumping cylinder <NUM>. The pump rod <NUM> is coupled to the piston <NUM> to move the piston <NUM> up and down in the chamber <NUM>. The pumping cylinder <NUM> is pivotably coupled to the manifold <NUM> via a pivot pin <NUM>. The pivot pin <NUM> extends into the pump port <NUM> (<FIG>). The pivot pin <NUM> has a channel <NUM> that fluidly couples the chamber <NUM> and the pump port <NUM>. Thus, fluid can be moved between the chamber <NUM> and the pump port <NUM>. When the pump rod <NUM> is moved up, hydraulic fluid from the reservoir <NUM> is drawn into the chamber <NUM>. When the pump rod <NUM> is moved down, the hydraulic fluid is pushed out of the chamber <NUM> toward the selector valve <NUM>.

In some examples, to increase sealing pressure between the rotor <NUM> and the disk <NUM>, the manual hydraulic override pump <NUM> includes means for forcing or biasing the rotor <NUM> into the disk <NUM>. For example, as shown in <FIG>, the manual hydraulic override pump <NUM> includes a piston <NUM> disposed in the manifold <NUM> to bias the rotor <NUM> into the disk <NUM> (to the right in <FIG>). In the illustrated example, the piston <NUM> is disposed in a bore <NUM> formed in the block <NUM>. The piston <NUM> extends outward from the bore <NUM> and into the cavity <NUM>. The bore <NUM> is isolated from the cavity <NUM> by a seal <NUM> (e.g., an O-ring) on the piston <NUM>. The piston <NUM> pushes against a back surface <NUM> of the rotor <NUM> to bias the rotor <NUM> into sealing engagement with the disk <NUM>. In the illustrated example, a thrust bearing <NUM> is disposed between the piston <NUM> and the back surface <NUM> of the rotor <NUM>. The thrust bearing <NUM> enables the rotor <NUM> to rotate smoothly relative to the piston <NUM> as the piston <NUM> applies pressure on the back surface <NUM> of the rotor <NUM>.

To bias the piston <NUM> against the rotor <NUM>, the block <NUM> and/or the manifold <NUM> includes a passageway <NUM> that is fluidly coupled to the fluid line <NUM> (<FIG>) in the manifold <NUM> between the pump port <NUM> (<FIG>) and the selector valve <NUM> (<FIG>). Therefore, when the hand pump <NUM> (<FIG>) is used to supply pressurized fluid to one of the first chamber <NUM> or the second chamber <NUM> (e.g., when the rotor <NUM> is in the first actuating position <NUM> or the second actuating position <NUM>), the bore <NUM> in the block <NUM> is also pressurized, which forces the piston <NUM> into the rotor <NUM>. In other words, the rotor <NUM> receives proportional feedback from the hand pump <NUM>. As such, the higher the pressure, the better the sealing performance. This pressure on the rotor <NUM> helps maintains a high pressure seal between the rotor <NUM> and the disk <NUM>, which is beneficial when pumping high pressure fluid through the rotor <NUM> and the disk <NUM>. This type of design may be referred to as a resilient seated design. When the rotor <NUM> is in the neutral position <NUM>, the pressure in the fluid line <NUM> (<FIG>) is reduce. As such, the pressure in the bore <NUM> is also reduced. In other examples, in addition to or as an alternative to being fluidly coupled to the fluid line <NUM>, the passageway can be fluidly coupled to another pressurized source, such as one or both of the fluid lines <NUM>, <NUM> (<FIG>). In the illustrated example of <FIG>, a spring <NUM> is disposed in the bore <NUM> to provide an initial biasing force on the piston <NUM> when the pressure in the bore <NUM> is relatively low (e.g., when initially switching from the neutral position to one of the first or second actuating positions).

<FIG> is an isolated perspective view of the disk <NUM>. The disk <NUM> has a first side <NUM> and a second side <NUM> opposite the first side <NUM>. The disk <NUM> is coupled to the wall <NUM> (<FIG>) of the manifold <NUM> in the cavity <NUM> (<FIG>) such that the second side <NUM> is in contact with the wall <NUM> (<FIG>). The second side <NUM> is substantially flat.

In the illustrated example, the disk <NUM> has four openings <NUM>, extending between the first and second sides <NUM>, <NUM>, that are aligned with the openings <NUM>-<NUM> (<FIG>) in the wall <NUM> (<FIG>). Thus, the openings <NUM> correspond to the pump port <NUM>, the reservoir port <NUM>, the first actuator port <NUM>, and the second actuator port <NUM>. In the illustrated example, the first side <NUM> includes annular raised ridges or rings <NUM> around the openings <NUM>. The annular raised ridges <NUM> create a tight sealing interface between the disk <NUM> and the rotor <NUM>, which is shown in further detail in <FIG>.

In the illustrated example, the disk <NUM> has a central opening <NUM>. The shaft <NUM> (<FIG>) extends through the central opening <NUM>. The disk <NUM> also has four fastener openings <NUM> to receiver fasteners (e.g., screws, bolts, etc.) for fastening the disk <NUM> to the manifold <NUM>. In other examples, the disk <NUM> may include more or fewer fastener openings. Additionally or alternatively, the disk may be coupled to the wall <NUM> of the manifold <NUM> via other mechanical and/or chemical fastening techniques (e.g., friction fit, welding, an adhesive, etc.).

<FIG> is an isolated perspective view of the rotor <NUM>. The body of the rotor <NUM> is shown as transparent in <FIG> to expose the internal passageways. The example rotor <NUM> has a sealing surface <NUM> (e.g., a first side or surface), the back surface <NUM> (e.g., a second side or surface) opposite the sealing surface <NUM>, and an outer peripheral surface <NUM> between the sealing surface <NUM> and the back surface <NUM>. The sealing surface <NUM> may also be referred to as a sealing face. The sealing surface <NUM> is to be engaged with the disk <NUM>, as shown in <FIG>. In the illustrated example, a central bore <NUM> is defined in the sealing surface <NUM> that extends partially into the rotor <NUM>. The shaft <NUM> (<FIG>) is to be inserted into the central bore <NUM> and coupled to the rotor <NUM>.

In the illustrated example, the sealing surface <NUM> includes pairs of openings that are connected by respective passageways or channels formed in the rotor <NUM>. In other words, the rotor <NUM> has passageways, each of which connects two of the openings in the sealing surface <NUM>. For example, the sealing surface <NUM> in the illustrated example has a first pair of openings 608a, 608b that are connected by a first passageway <NUM> formed in the rotor <NUM>, a second pair of openings 612a, 612b that are connected by a second passageway <NUM> formed in the rotor <NUM>, and a third pair of openings 616a, 616b that are connected by a third passageway <NUM> formed in the rotor <NUM>. The first, second, and third passageways <NUM>, <NUM>, <NUM> are isolated from each other and are parallel to each other. Depending on the orientation of the rotor <NUM>, the first, second, and/or third pairs of openings 608a, 608b, 612a, 612b, 614a, 614b may align with the openings <NUM> in the disk <NUM> (<FIG>) to fluidly couple corresponding ones of the openings <NUM>-<NUM> in the manifold <NUM> (<FIG>), as shown in further detail in connection with <FIG>.

In the illustrated example of <FIG>, the rotor <NUM> has a first notch <NUM> formed in the sealing surface <NUM> that extends to a first flattened surface <NUM> on the outer peripheral surface <NUM>. The rotor <NUM> also has a second notch <NUM> formed in the sealing surface <NUM> that extends to a second flattened surface <NUM> on the outer peripheral surface <NUM> opposite the first notch <NUM> and the first flattened surface <NUM>. When the rotor <NUM> is disposed in the cavity <NUM>, the first and second flattened surfaces <NUM>, <NUM> enable the first and second notches <NUM>, <NUM> to be in fluid communication via the cavity <NUM>. The rotor <NUM> may be rotated to align certain ones of the openings <NUM>-<NUM> (<FIG>) with the notches <NUM>, <NUM> to fluidly connect certain ones of the openings <NUM>-<NUM> via the cavity <NUM>. The first, second, and third pairs of openings 608a, 608b, 612a, 612b, 616a, 616b and the first and second notches <NUM>, <NUM> are equally spaced from a central axis <NUM> of the rotor <NUM>.

In the illustrated example, the rotor <NUM> has first, second, and third detent grooves 628a, 628b, 628c formed in the outer peripheral surface <NUM>. The first, second, and third detent grooves 628a, 628b, 628c are arranged to receive a detent pin to hold the rotor <NUM> in a specific position, as shown in further detail in conjunction with <FIG>.

<FIG> shows the alignment between the pairs of openings 608a, 608b, 612a, 612b, 616a, 616b and the notches <NUM>, <NUM> in the rotor <NUM> (<FIG>) with the openings <NUM>-<NUM> in the manifold <NUM> (<FIG>) when the rotor <NUM> is in the neutral position <NUM>. In the neutral position <NUM>, the first notch <NUM> is aligned with the first opening <NUM> (corresponding to the first actuating port <NUM> for the first chamber <NUM> (<FIG>), labeled "C1"). As such, the first actuating port <NUM> (<FIG>) is in fluid communication with the cavity <NUM> (<FIG>). Similarly, the second notch <NUM> is aligned with the second opening <NUM> (corresponding to the second actuator port <NUM> for the second chamber <NUM> (<FIG>), labeled "C2"). Therefore, the second actuating port <NUM> (<FIG>) is also in fluid communication with the cavity <NUM> (<FIG>). Thus, when the rotor <NUM> is in the neutral position <NUM>, the first and second actuating ports <NUM>, <NUM> (<FIG>) are fluidly coupled by the cavity <NUM> (<FIG>). As such, the pressures in first and second chambers <NUM>, <NUM> of the hydraulic override cylinder <NUM> (<FIG>) are equalized.

Further, as shown in <FIG>, the third pair of openings 616a, 616b in the rotor <NUM> are aligned with the third opening <NUM> (corresponding to the pump port <NUM> for the hand pump <NUM> (<FIG>), labeled "P") and the fourth opening <NUM> (corresponding to the reservoir port <NUM> for the reservoir <NUM> (<FIG>), labeled "R"), respectively. Therefore, when the rotor <NUM> is in the neutral position <NUM>, the third passageway <NUM> fluidly couples the pump port <NUM> and the reservoir port <NUM> and, thus, fluidly couples the hand pump <NUM> and the reservoir <NUM>. As such, pumping the hand pump <NUM> does not have any effect on the first or second chambers <NUM>, <NUM> (<FIG>). Further, as shown in <FIG>, a portion of the fluid line <NUM> is fluidly coupled to the cavity <NUM>. Therefore, in the neutral position, the first and second actuator ports <NUM>, <NUM> (<FIG> and <FIG>) are also fluidly coupled to the reservoir port <NUM> (<FIG>) and, thus, the pump port <NUM> (<FIG>). Therefore, all of the ports are fluidly coupled and the fluid pressure in fluid lines is equalized. In the neutral position, the first and second pairs of openings 608a, 608b, 612a, 612b are not aligned with any openings.

<FIG> shows the alignment between the pairs of openings 608a, 608b, 612a, 612b, 616a, 616b and the notches <NUM>, <NUM> in the rotor <NUM> (<FIG>) with the openings <NUM>-<NUM> in the manifold <NUM> (<FIG>) when the rotor <NUM> is in the first actuation position <NUM>. As shown in <FIG>, the rotor <NUM> has been rotated (e.g., via the handwheel <NUM> (<FIG>)) counter-clockwise <NUM>° from the neutral position <NUM> in <FIG>. In the first actuating position <NUM>, the first pair of openings 608a, 608b is aligned with the third opening <NUM> (corresponding to the pump port <NUM> for the hand pump <NUM> (<FIG>), labeled "P") and the first opening <NUM> (corresponding to the first actuating port <NUM> for the first chamber <NUM> (<FIG>), labeled "C1"), respectively. Thus, when the rotor <NUM> is in the first actuating position <NUM>, the first passageway <NUM> fluidly couples the pump port <NUM> and the first actuating port <NUM>. As a result, hydraulic fluid can be pumped from the hand pump <NUM> into the first chamber <NUM> of the actuator <NUM>.

Further, in the first actuating position <NUM>, the second pair of openings 612a, 612b is aligned with the second opening <NUM> (corresponding to the second actuator port <NUM> for the second chamber <NUM> (<FIG>), labeled "C2") and the fourth opening <NUM> (corresponding to the reservoir port <NUM> for the reservoir <NUM> (<FIG>), labeled "R"), respectively. Thus, when the rotor <NUM> is in the first actuating position <NUM>, the second passageway <NUM> fluidly couples the second actuating port <NUM> and the reservoir port <NUM>. As a result, hydraulic fluid from the second chamber <NUM> of the actuator <NUM> can be pushed back into the reservoir <NUM> as the piston <NUM> of the hydraulic override cylinder <NUM> moves.

<FIG> shows the alignment between the pairs of openings 608a, 608b, 612a, 612b, 616a, 616b and the notches <NUM>, <NUM> in the rotor <NUM> (<FIG>) with the openings <NUM>-<NUM> in the manifold <NUM> (<FIG>) when the rotor <NUM> is in the second actuating position <NUM>. As shown in <FIG>, the rotor <NUM> has been rotated (e.g., via the handwheel <NUM> (<FIG>)) clockwise <NUM>° from the neutral position <NUM> in <FIG>. In the second actuating position <NUM>, the second pair of openings 612a, 612b is aligned with the third opening <NUM> (corresponding to the pump port <NUM> for the hand pump <NUM> (<FIG>), labeled "P") and the second opening <NUM> (corresponding to the second actuator port <NUM> for the second chamber <NUM> (<FIG>), labeled "C2"), respectively. Thus, when the rotor <NUM> is in the second actuating position <NUM>, the second passageway <NUM> fluidly couples the pump port <NUM> and the second actuating port <NUM>. As a result, hydraulic fluid can be pumped from the hand pump <NUM> into the second chamber <NUM> of the actuator <NUM>.

Further, in the second actuating position <NUM>, the first pair of openings 608a, 608b is aligned with the first opening <NUM> (corresponding to the first actuating port <NUM> for the first chamber <NUM> (<FIG>), labeled "C1") and the fourth opening <NUM> (corresponding to the reservoir port <NUM> for the reservoir <NUM> (<FIG>), labeled "R"), respectively. Thus, when the rotor <NUM> is in the second actuating position <NUM>, the first passageway <NUM> fluidly couples the first actuating port <NUM> and the reservoir port <NUM>. As a result, hydraulic fluid from the first chamber <NUM> of the actuator <NUM> can be pushed back into the reservoir <NUM> as the piston <NUM> of the hydraulic override cylinder <NUM> moves.

<FIG> is a rear view of the rotor <NUM> in the cavity <NUM> of the manifold <NUM>. As shown in <FIG>, a detent pin <NUM> is disposed in a bore <NUM> formed in the manifold <NUM>. A spring <NUM> is disposed in the bore <NUM> and biases the detent pin <NUM> toward the rotor <NUM>. In the illustrated example, the detent pin <NUM> is settled in the second detent groove 628b of the rotor <NUM>, which corresponds to the neutral position of the rotor <NUM>. The detent pin <NUM> holds the rotor <NUM> in the neutral position until a sufficient rotational force is applied to rotate the rotor <NUM>. When the rotor <NUM> is rotated, the detent pin <NUM> is pushed back into the bore <NUM>. When the rotor <NUM> reaches one of the first or third detent grooves 628a, 628c (which correspond to the first actuating position and the second actuating position, respectively), the detent pin <NUM> settles into the corresponding detent groove to hold the rotor <NUM>. This resistance provides a haptic feeling or feedback to the human operator to indicate when a corresponding position has been reached. In the illustrated example, the outer peripheral surface <NUM> of the rotor <NUM> is spaced apart from an inner sidewall <NUM> defining of the cavity <NUM>. In other examples, the diameter of the rotor <NUM> may be larger, such that the outer peripheral surface <NUM> of the rotor <NUM> is closer to the inner sidewall <NUM> of the cavity <NUM> and/or in contact with (e.g., slides along) the inner sidewall <NUM> of the cavity <NUM>.

<FIG> is a perspective view of the rotor <NUM> and the shaft <NUM>. The shaft <NUM> is coupled to and extends from the rotor <NUM> (e.g., along a central axis of the rotor <NUM>). As shown in <FIG>, the shaft <NUM> is partially disposed in the central bore <NUM> in the rotor <NUM>. To couple the rotor <NUM> and the shaft <NUM>, a spring pin <NUM> (which may be referred to as a roll pin) extends through the rotor <NUM> and the shaft <NUM>. As such, the shaft <NUM> can rotate the rotor <NUM>.

<FIG> is a cross-sectional view of the rotor <NUM> and the shaft <NUM> taken along line B-B of <FIG>. <FIG> also illustrates the sealing interface between the rotor <NUM> and the disk <NUM>. The sealing surface <NUM> of the rotor <NUM> is in contact with the disk <NUM>. An enlarged view of the encircled section in <FIG> is shown in the callout.

In some examples, to provide a tight sealing interface between the disk <NUM> and the sealing surface <NUM> of the rotor <NUM>, the outer surfaces of the annular raised ridges <NUM> are convex or bowed outward toward the sealing surface <NUM> of the rotor <NUM>. For example, as shown in the callout in <FIG>, a sealing surface <NUM> of the annular raised ridge <NUM> is convex toward the opening <NUM>. This creates a single line of contact (at point <NUM>), in a circle, between the sealing surfaces <NUM>, <NUM> immediately around the opening <NUM>. This line of contact ensures a full, complete engagement between the sealing surfaces <NUM>, <NUM> to achieve maximum sealing performance and prevent leakage. Further, the convex profile reduces or eliminates trapped air between the rotor <NUM> and the disk <NUM> that could cause vacuum trapping and that would require more force to rotate the rotor <NUM> out of a position. Thus, the convex profile minimizes pressure drop to achieve the highest flow performance. The other annular raised ridges <NUM> are similarly convex shaped and form a line of contact around the respective openings <NUM>.

While in the illustrated example the first side <NUM> of the disk <NUM> includes the annular raised ridges <NUM>, in other examples, no annular raised ridges are formed around the openings <NUM>. Instead, the first side <NUM> of the disk <NUM> may be substantially flat or smooth. In some such examples, small convex features (e.g., bumps) may be formed around each of the openings <NUM> to create the lines of contact around each of the openings <NUM>.

In some examples, both the rotor <NUM> and the disk <NUM> are constructed of a hard metal, such as tungsten carbide. The metal-to-metal contact between the rotor <NUM> and the disk <NUM> creates an excellent seal with minimal (if any) wear. Tungsten carbide, for example, provides high resistance to erosion, wear, abrasion, and galling where the porosity is non-existent. Thus, the example metal-to-metal seal has better sealing performance and a longer life span than known override pumps that utilize rubber seals. In some examples, the rotor <NUM> is constructed of a single unitary part or component (e.g., a single piece of tungsten carbide). For example, the rotor <NUM> may be constructed of two more pieces of tungsten carbide that are sintered together during a sintering operation to form a single part or component of tungsten carbide. In another example, the rotor <NUM> may be constructed of a single piece of tungsten carbide (e.g., molded in the shape of the rotor <NUM>) and cross-holes may be drilled in the rotor <NUM>. Then, the ends of the cross-holes can be plugged, and the resulting passageways form the passageways <NUM>, <NUM>, <NUM>. Similarly, in some examples, the disk <NUM> is constructed of a single unitary part or component (e.g., a single piece of tungsten carbide). The rotor <NUM> and/or the disk <NUM> may be manufactured utilizing a powered metal sintering process. In other examples, the rotor <NUM> and/or the disk <NUM> may be constructed of other materials (e.g., stainless steel) and/or constructed of two or more parts or components coupled together. In other examples, the rotor <NUM> and/or the disk <NUM> may be manufactured using other manufacturing process, such as additive manufacturing (e.g., 3D printing).

In some examples the sealing surface <NUM> of the rotor <NUM> and the sealing surface <NUM> of the annular raised ridges <NUM> of the disk <NUM> are polished to a mirror finish (e.g., via a grinding or polishing process, using a PDC bit with industrial diamond, etc.). As such, the sealing surfaces <NUM>, <NUM> are extremely smooth and provide excellent sealing contact between the rotor <NUM> and the disk <NUM>. Further, by having the annular raised ridges <NUM>, less surface area of the disk <NUM> has to be polished, which reduces manufacturing time and costs.

While in some examples the manual hydraulic override pump <NUM> includes the disk <NUM> to form the sealing interface between the rotor <NUM> and the wall <NUM> in the manifold <NUM>, in other examples, the disk <NUM> may not be included. Instead, the rotor <NUM> may interface directly with (e.g., contact) the wall <NUM> of the manifold <NUM>. In some such examples, raised and/or convex features may be formed around the openings <NUM>-<NUM> in the wall, similar to the annular raised ridges <NUM> on the disk <NUM>.

<FIG> is an enlarged cross-sectional view of the rotor <NUM>, the shaft <NUM>, and the spring pin <NUM> that couples the rotor <NUM> and the shaft <NUM>. As shown in <FIG>, the spring pin <NUM> extends through an opening <NUM> in the rotor <NUM> (that traverses the central bore <NUM>) and an opening <NUM> in the shaft <NUM> aligned with the opening <NUM> in the rotor <NUM>. To assemble the shaft <NUM> and the rotor <NUM>, an end <NUM> of the shaft <NUM> is inserted into the central bore <NUM> of the rotor <NUM>. The openings <NUM>, <NUM> are aligned. Then, the spring pin <NUM> is inserted through the openings <NUM>, <NUM>. In some examples, the spring pin <NUM> is held in the opening <NUM> of the shaft <NUM> via interference fit (e.g., friction fit). For example, the diameter of the opening <NUM> of the shaft <NUM> is slightly smaller than the outer diameter of the spring pin <NUM>. As a result, the spring pin <NUM> is compressed when being inserted into the opening <NUM> of the shaft <NUM> and expands into the sides of the opening <NUM> of the shaft <NUM>. The friction between the spring pin <NUM> and the opening <NUM> of the shaft <NUM> holds the spring pin <NUM> in place. In some examples, the spring pin <NUM> has a c-shaped cross-section.

As disclosed above, in some examples the rotor <NUM> is constructed of a relatively hard material such as tungsten carbide. While extremely hard, tungsten carbide is brittle or fragile under impact forces. Therefore, to reduce the risk of compromising (e.g., cracking) the rotor <NUM> when inserting the spring pin <NUM> into the opening <NUM> of the rotor <NUM>, the diameter of the opening <NUM> in the rotor <NUM> is larger than the outer diameter of the spring pin <NUM>. As such, any impact forces that may be applied to the spring pin <NUM> when inserting the spring pin <NUM> (e.g., by hammering the spring pin <NUM> into the opening <NUM>) are not transferred directly to the rotor <NUM>.

As disclosed above, a clearance exists between the spring pin <NUM> and the opening <NUM> in the rotor <NUM>. As a result, the rotor <NUM> can pivot relative to the shaft <NUM> about an axis (e.g., extending out of the page) that is perpendicular to a longitudinal axis of the shaft <NUM>. For example, the rotor <NUM> can pivot in the direction of the arrows shown in <FIG>. As such, if the shaft <NUM> is not perfectly centered in the central bore <NUM>, the clearance enables the rotor <NUM> to pivot or twist relative to the shaft <NUM> so that the sealing surface <NUM> of the rotor <NUM> settles flat or parallel to the disk <NUM> (<FIG>). This clearance ensures a tight sealing interface between the rotor <NUM> and the disk <NUM>. This clearance also allows for lower manufacturing tolerances, which reduces manufacturing time and costs. In some examples, the spring pin <NUM> is constructed of stainless steel. In other examples, the spring pin <NUM> can be constructed of other materials.

In some examples, the manual hydraulic override pump <NUM> includes means for automatically moving the handwheel <NUM> back to the neutral position. For example, as shown in <FIG>, the manual hydraulic override pump <NUM> includes the pneumatic reset cylinder <NUM>. A top <NUM> of the pneumatic reset cylinder <NUM> is coupled to a bracket <NUM> that is coupled to the manifold <NUM>.

<FIG> is a partial cross-sectional view of the top <NUM> of the pneumatic reset cylinder <NUM> from callout A of <FIG>. As shown in <FIG>, the top <NUM> of the pneumatic reset cylinder <NUM> is pivotably coupled to the bracket <NUM> via a pin <NUM> that is coupled to and extends from the bracket <NUM>. As such, the top <NUM> of the pneumatic reset cylinder <NUM> can pivot about the pin <NUM>.

<FIG> is a partial cross-sectional view of a bottom of the pneumatic reset cylinder <NUM> from callout B of <FIG>. As shown in <FIG>, a shaft <NUM> extends from a bottom <NUM> of the pneumatic reset cylinder <NUM>. The shaft <NUM> is connected to a piston within the pneumatic reset cylinder <NUM>. A pivot pin <NUM> is coupled to and extends outward from the shaft <NUM> and into the handwheel <NUM>. When a human operator rotates the handwheel <NUM> to the first actuating position (counter-clockwise) or the second actuating position (clockwise), the piston shaft <NUM> is extended or pulled out of the bottom <NUM> of the pneumatic reset cylinder <NUM>. Additionally, the pneumatic reset cylinder <NUM> pivots about the pivot pin <NUM>.

For example, <FIG> shows the handwheel <NUM> after being rotated (clockwise) to the first actuating position. As shown, the shaft <NUM> has been pulled from the bottom <NUM> of the pneumatic reset cylinder <NUM>. The pneumatic reset cylinder <NUM> has also pivoted (about the pivot pin <NUM> (<FIG>)). The handwheel <NUM> has been cross-sectioned in <FIG> to expose example first and second stop pins <NUM>, <NUM> that extend from the plate <NUM> or another structure (e.g., the manifold <NUM> (<FIG>)). The tab <NUM> on the handwheel <NUM> engages the second stop pin <NUM> when the handwheel <NUM> is rotated to the first actuating position (counter-clockwise), and the tab <NUM> on the handwheel <NUM> engages the first stop pin <NUM> when the handwheel <NUM> is rotated to the second actuating position (clockwise). The first and second stop pins <NUM>, <NUM> form limits that prevent the handwheel <NUM> (and, thus, the rotor <NUM>) from being rotated beyond the first and second actuating positions. In other examples stop pins or other tabs or structures can be employed inside of the manifold <NUM> to limit movement. In the illustrated example, third indicia <NUM> (e.g., "AUTO") is provided on the plate <NUM> to indicate with the handwheel <NUM> is in the neutral position.

When the pneumatic reset cylinder <NUM> is actuated, the piston shaft <NUM> is retracted or pulled back into the pneumatic reset cylinder <NUM>. This force overcomes the force from the detent pin <NUM> (<FIG>) and causes the handwheel <NUM> to rotate back to the neutral position. As such, the handwheel <NUM> is rotated back to the neutral position and the pneumatic reset cylinder <NUM> is pivoted back to the vertical position shown in <FIG>. The pneumatic reset cylinder <NUM> may be actuated by receiving high pressure air provided by an air source (e.g., a compressed air tank). As shown in <FIG>, a tube <NUM> is coupled to the pneumatic reset cylinder <NUM> to provide high pressure air to the pneumatic reset cylinder <NUM>. The pneumatic reset cylinder <NUM> may be actuated remotely, for example, via a control signal from a control room. In other examples, other types of devices may be used, such as a hydraulic powered device or an electrical powered device (e.g., an electro-mechanical solenoid). In some examples, an additional device may be used to retract the detent pin <NUM> (<FIG>) from the respective detent groove 628a-628c (<FIG>) to reduce the force required by the pneumatic reset cylinder <NUM> to rotate the handwheel <NUM> back to the neutral position.

As an example operation, assume the pump <NUM> for the actuator <NUM> has become inoperable and a human operator desires to move the flow control member <NUM> of the valve <NUM> to a specific position (e.g., fully closed, fully open, etc.). The operator can turn the handwheel <NUM> of the example manual hydraulic override pump <NUM> from the neutral position to the first actuating position or the second actuating position. Then, the human operator can use the lever <NUM> of the hand pump <NUM> to pump fluid to the actuator <NUM> to move the flow control member of the valve <NUM> to the desired position. Once the desired position of the flow control member <NUM> is reached, the operator can then leave the handwheel <NUM> (and, thus, the selector valve <NUM>) in the current state. Then, at a later time, assume the pump <NUM> becomes operational again. The operator or another person can send a signal from a remote location (e.g., a control room) to activate the pneumatic reset cylinder <NUM>, which moves the handwheel <NUM> (and, thus, the selector valve <NUM>) back to the neutral position. Thus, the pneumatic reset cylinder <NUM> enables remote resetting of the handwheel <NUM> so that an operator does not have to manually turn the handwheel <NUM> back to the neutral position.

In other examples, the manual hydraulic override pump <NUM> may not include a mechanism or means for automatically moving the handwheel <NUM> back to the neutral position. In such an example, the human operator manually rotates the handwheel <NUM> back to the neutral position.

While in the illustrated examples the rotor <NUM> is used to fluidly couple the four openings <NUM>-<NUM> in the wall <NUM> of the manifold <NUM> (<FIG>), in other examples, the rotor <NUM> can be used to fluidly couple more (e.g., five, six, etc.) or fewer openings or fluid lines. For example, the wall <NUM> may have eight openings, and the rotor <NUM> may have more or fewer pairs of openings connected by passageways to connect the various openings. Also, while in the illustrated example the rotor <NUM> is movable between three positions, in other examples, the rotor <NUM> can be moveable to more or fewer positions.

Further, while the example hydraulic override pump <NUM> is described in connection with an actuator for a valve, it is understood that the example hydraulic override pump <NUM> can similarly be used in connection with any other type of device, such as a pressure regulator, a metering valve, and/or any other device controlled by an actuator.

Claim 1:
An apparatus (<NUM>) comprising:
a manifold (<NUM>) including:
a reservoir port (<NUM>) to be fluidly coupled to a reservoir (<NUM>) of fluid;
a pump port (<NUM>) to be fluidly coupled to a pump (<NUM>);
a first actuator port (<NUM>) to be fluidly coupled to a first chamber (<NUM>) of an actuator (<NUM>); and
a second actuator port (<NUM>) to be fluidly coupled to a second chamber (<NUM>) of the actuator (<NUM>);
a rotor (<NUM>) disposed in a cavity (<NUM>) formed in the manifold (<NUM>), the rotor (<NUM>) having a sealing surface (<NUM>) with a first pair of openings (608a, 608b) connected by a first passageway (<NUM>) formed in the rotor (<NUM>), a second pair of openings (612a, 612b) connected by a second passageway (<NUM>) formed in the rotor (<NUM>), and a third pair of openings (616a, 616b) connected by a third passageway (<NUM>) formed in the rotor (<NUM>), the rotor (<NUM>) rotatable between:
a first actuating position in which the first passageway (<NUM>) of the rotor (<NUM>) fluidly couples the first actuator port (<NUM>) and the pump port (<NUM>), and the second passageway (<NUM>) of the rotor (<NUM>) fluidly couples the second actuator port (<NUM>) and the reservoir port (<NUM>);
a second actuating position in which the second passageway (<NUM>) of the rotor (<NUM>) fluidly couples the second actuator port (<NUM>) and the pump port (<NUM>), and the first passageway (<NUM>) of the rotor (<NUM>) fluidly couples the first actuator port (<NUM>) and the reservoir port (<NUM>); and
a neutral position in which the first actuator port (<NUM>) and the second actuator port (<NUM>) are fluidly coupled via the cavity (<NUM>) in which the rotor (<NUM>) is disposed, and the third passageway (<NUM>) fluidly couples the pump port (<NUM>) and the reservoir port (<NUM>).