Valve incorporating a turbine for energy recovery

Abstract

An exemplary valve includes a seat member; a spool configured to seat on the seat member to block fluid flow from the first port to the second port when the valve is in a closed state, where fluid at the first port exerts a fluid force on the spool; a spring biasing the spool toward the seat member such that the fluid force overcomes the biasing force, causing the spool to move proximally and away from the seat member thereby allowing fluid flow from the first port to the second port through a flow through area formed between the spool and the seat member; a turbine configured to rotate when fluid flowing through the flow through area flows downstream through the turbine; and a generator coupled to the turbine such that the generator generates power when the turbine rotates.

Description

Technical Field

[0001] The present invention relates to a valve incorporating a turbine for energy recovery.

[0002] [Cross - Reference to Related Applications] This application claims priority to U.S. Patent Application No. 17 / 739,293, filed May 9, 2022, entitled "Valve with an Integrated Turbine for Energy Harvesting", which claims priority to U.S. Provisional Patent Application No. 63 / 209,441, filed Jun. 11, 2021, entitled "Pressure - Compensated Flow Control Valve with an Integrated Turbine for Energy Harvesting or Flow Rate Sensing", and the entire contents of all of those documents are hereby incorporated by reference as if fully set forth herein.

Background Art

[0003] A hydraulic valve directs the flow of a liquid medium, usually oil, through a hydraulic system. The direction of the oil flow is determined by the position of a movable element such as a spool, piston, or poppet. The size of the valve can be determined by the maximum flow rate of the hydraulic system passing through the valve and the maximum pressure of the system.

[0004] The movable element of the valve can be disposed within a housing or sleeve and can be made movable by fluid forces. When the spool moves, a flow area or orifice is created, which allows fluid flow from a first port to a second port.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Whenever fluid flows through an orifice at a specific flow rate, causing a pressure drop across the orifice, power is lost in the form of heat generated when the fluid flows through the valve. The power loss can be the product of the fluid flow rate and the pressure difference across the orifice. Therefore, in order to make the system more efficient, it may be desirable to recover at least a portion of such power loss. In view of these and other considerations, the present disclosure is presented herein.

Means for Solving the Problem

[0006] The present disclosure describes embodiments related to a valve incorporating a turbine for energy recovery.

[0007] In a first exemplary embodiment, the present disclosure describes a valve. The valve includes a seat member; a spool configured to seat on the seat member when the valve is in a closed state and block the flow of fluid from a first port to a second port, wherein the fluid at the first port applies a fluid force to the spool in the proximal direction; a spring applying a biasing force to the spool in the distal direction toward the seat member, such that when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling the flow of fluid from the first port to the second port through a flow-through region formed between the spool and the seat member; a turbine configured to rotate when the fluid flowing through the flow-through region flows downstream through the turbine, and the turbine is attached to a turbine shaft configured to rotate with the turbine; and a generator coupled to the turbine shaft such that the generator generates electrical power when the turbine shaft rotates with the turbine.

[0008] In a second exemplary implementation, the present disclosure describes a system. The system includes a hydraulic actuator having a first chamber and a second chamber; a fluid source; a fluid reservoir; a direction control valve having an inlet port fluidly coupled to the fluid source, a first work port fluidly coupled to the first chamber of the hydraulic actuator, a second work port fluidly coupled to the second chamber of the hydraulic actuator, and a return port; and a valve of the first exemplary implementation. The first port of the valve is fluidly coupled to the return port of the direction control valve, and the second port of the valve is fluidly coupled to the fluid reservoir.

[0009] In a third exemplary implementation, the present disclosure describes a method. The method includes operating a valve in a closed state where a spool seats on a seat member to block fluid flow from a first port to a second port, fluid at the first port applies a fluid force to the spool in a proximal direction, and a spring applies a biasing force to the spool in a distal direction toward the seat member; opening a main flow path that enables fluid flow from the first port to the second port through a flow region formed between the spool and the seat member by the fluid force overcoming the biasing force to move the spool in the proximal direction away from the seat member; rotating a turbine coupled to a generator such that the generator generates power when the turbine rotates as fluid flows through the main flow path; and opening a bypass flow path that enables a portion of the fluid to bypass the turbine and flow directly from the first port to the second port by moving the spool further in the proximal direction as the pressure level of the fluid at the first port increases.

[0010] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, implementations, and characteristics described above, further aspects, implementations, and characteristics will become apparent by reference to the figures and the following detailed description.

[0011] The features considered to be characteristic of the illustrative examples and the novel characteristics are set forth in the appended claims. However, the illustrative examples as well as preferred modes of use, further objects and descriptions thereof will be best understood by reference to the following detailed description of the illustrative examples of the present disclosure in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Best Mode for Carrying Out the Invention

[0013] In each example, a flow control valve (flow control valve) can have a movable element such as a spool, and the movable element blocks the flow of fluid from a first port to a second port until the pressure level at the first port exceeds a threshold pressure. When the pressure level reaches the threshold pressure, the spool can move to allow the flow of fluid from the first port to the second port.

[0014] In the disclosed exemplary valve, a turbine is incorporated within the valve. The term "turbine" is used herein to refer to a rotary mechanical device (rotary machine) such as an impeller that extracts energy from a fluid flow. As the fluid flows through the turbine, the fluid causes the turbine to rotate, converting it into kinetic energy, and this kinetic energy can be used to produce an effective action.

[0015] In one example, the turbine is coupled to a shaft that rotates within a generator. Thus, when the shaft rotates, electrical power is generated by the generator. In such a configuration, at least a portion of the hydraulic power is recovered in the form of electrical power, which in other cases would be lost in the form of heat when the fluid flows through the valve. Such recovered electrical power can be used to enhance the efficiency of other parts of the hydraulic system or, alternatively, to supply electrical power to parts of the machine that do not otherwise have access to electrical power.

[0016] FIG. 1 shows a side cross-sectional view of a valve 100 incorporating a turbine and a generator for energy recovery, according to an exemplary implementation. The valve 100 can be inserted into or screwed into a manifold having ports corresponding to the ports of the valve 100 described below, and the manifold can fluidly couple the valve 100 to other components of the hydraulic system.

[0017] The valve 100 includes a housing 102 having an internal longitudinal cylindrical cavity (a longitudinally extending cylindrical cavity). The longitudinal cylindrical cavity of the housing 102 is configured to accommodate the components of the valve 100. The valve 100 further includes a sleeve 104, which is partially fixedly disposed within the longitudinal cylindrical cavity of the housing 102. The sleeve 104 has an individual longitudinal cylindrical cavity inside.

[0018] Valve 100 includes a nose piece 106, which is coupled to a sleeve 104 and disposed at the distal end of the sleeve 104. The nose piece 106 has a plurality of through holes, such as through hole 107 and through hole 108, which are arranged in a circular array at the distal end of the nose piece 106. Valve 100 also includes a seat member (seat member) 110, and the seat member 110 is coupled to the nose piece 106 via a screw 111.

[0019] The valve further includes a stator (stator vane row) 112, which is annular and disposed radially between the seat member 110 and the sleeve 104. In one example, the stator 112 includes a plurality of blades or fins, which are used to direct the flow of fluid and spin it to increase the energy recovery efficiency as described below.

[0020] Valve 100 also includes a spool 114, which is disposed within the longitudinal cylindrical cavity of the sleeve 104. The spool 114 can also be called a piston or a poppet. The spool 114 is slidably received within the sleeve 104 such that the outer surface of the spool 114 slides against the inner surface of the sleeve 104. Accordingly, the spool 114 is axially movable within the sleeve 104. The term "slidably received" is used throughout this specification to indicate that the first component (e.g., the spool 114) is not stationary, locked, or fixedly disposed within the valve 100, but rather is capable of moving relative to the second component (e.g., the sleeve 104).

[0021] Furthermore, the seat member 110 operates as a seat for the spool 114. In particular, when the valve 100 is in the closed state shown in FIG. 1, the inner surface of the spool 114 fits snugly against the seat member 110 at the seat (seat) 115.

[0022] The valve 100 includes a first port 116 at the distal end of the sleeve 104. The first port 116 includes, for example, a plurality of through holes 107, 108 in the nose piece 106. The valve 100 further includes a second port 118. The second port 118 includes two sets of intersecting holes, and each set is formed in the sleeve 104 in a circumferential arrangement (circumferential array). The first set of intersecting holes can be referred to as main flow intersecting holes and includes, for example, a main flow intersecting hole 119A and a main flow intersecting hole 119B. The second set of intersecting holes can be referred to as bypass flow intersecting holes and includes, for example, a bypass flow intersecting hole 120A and a bypass flow intersecting hole 120B. The first set of intersecting holes (e.g., main flow intersecting holes 119A, 119B) and the second set of intersecting holes (e.g., bypass flow intersecting holes 120A, 120B) are axially spaced apart from each other along the length of the sleeve 104.

[0023] As shown in FIG. 1, the spool 114 has a plurality of spool intersecting holes, such as a spool intersecting hole 121A and a spool intersecting hole 121B, which are formed in the spool 114 in a circumferential arrangement (circumferential array). In the position shown in FIG. 1, the spool 114 blocks the bypass flow intersecting holes 120A, 120B. However, in the position shown in FIG. 1, the main flow intersecting holes 119A, 119B are fluidly coupled to the spool intersecting holes 121A, 121B of the spool 114.

[0024] The term "fluidly coupled" is used throughout this specification to indicate that fluid can flow or pass between two fluid passages, chambers, ports, or openings. The term "block (prevent)" is used throughout this specification to indicate, for example, substantially preventing fluid flow except for a leakage flow of a few drops per minute or a minimum. The term "hole" is generally used in this specification to indicate, for example, a hollow location (e.g., a cavity) in a solid body or surface. The term "cross-hole" is used in this specification to include any type of opening (e.g., a slot, window, hole, etc.) formed to intersect or cross the passage of another hole, cavity, or channel.

[0025] The valve 100 further includes a turbine 122, which is disposed within the spool 114 and attached to a turbine shaft 124. The turbine 122 is attached to the turbine shaft 124 such that the turbine shaft 124 rotates with the rotation of the turbine 122.

[0026] FIG. 2 shows a perspective view of the turbine 122 according to an exemplary implementation, and FIG. 3 shows a perspective cross-sectional view of the turbine 122. The turbine 122 has a plurality of fins or blades 200 disposed on the outer surface of the turbine 122. When the fluid strikes (collides with) the blades 200 at a sufficient speed, the turbine 122 rotates.

[0027] The turbine 122 is hollow so that the turbine shaft 124 can be disposed therethrough. The turbine 122 has a hexagonal inner surface 202, and the turbine shaft 124 has a shaft portion 125 (see FIG. 1) with a corresponding hexagonal outer surface to facilitate the attachment of the turbine 122. In such a configuration, when the turbine 122 rotates, the turbine shaft 124 rotates therewith.

[0028] The turbine 122 further includes an inward flange portion (inner flange portion) 204, against which the shaft portion 125 abuts. In this way, the turbine 122 is prevented from moving in the proximal direction.

[0029] Returning to FIG. 1, the distal end of the turbine shaft 124 is received within the seat member 110 and is supported by a radial bearing 126 (e.g., a ball bearing) that is at least partially attached within the seat member 110. The radial bearing 126 maintains the turbine shaft 124 centered and facilitates (promotes) its low-friction rotation.

[0030] The valve 100 further includes a spring 127, a spring cap 128, a seal carrier 130, and a seal support member 132 disposed within the housing 102. The spring cap 128, the seal carrier 130, and the seal support member 132 are ring-shaped and are attached to the turbine shaft 124.

[0031] The seal carrier 130 and the seal support member 132 are fixedly disposed within the housing 102 and are configured to support radial seals such as the seals 133 and 134. The spring cap 128 abuts against the seal carrier 130 and is thus also stationary.

[0032] The proximal end of the spring 127 abuts against the spring cap 128, and the distal end of the spring 127 abuts against the spool 114. In such a configuration, the spring 127 applies a biasing force to the spool 114 in the distal direction toward the seat member 110 so that the spool 114 seats on the seat portion 115 when the valve 100 is in the closed state.

[0033] The valve 100 further includes a thrust bearing 136 attached to the turbine shaft 124. The thrust bearing 136 is held axially between the spring cap 128 and the seal carrier 130. The thrust bearing 136 can be any type of thrust bearing such as a thrust ball bearing, a cylindrical thrust roller bearing, a tapered roller thrust bearing, a spherical roller thrust bearing, a fluid bearing, a magnetic bearing, or a needle bearing.

[0034] The thrust bearing 136 facilitates (promotes) the rotation of the turbine shaft 124 by virtue of low friction. In particular, the thrust bearing 136 has a distal race 138 against which the extended shaft portion 139 of the turbine shaft 124 abuts. The thrust bearing 136 also includes a proximal race 140 which is configured as a cage (e.g., a nylon cage) that contacts (is connected to) the seal carrier 130. The proximal race 140 is configured as a carrier or retainer for the balls of the thrust bearing 136. In such a configuration, when the turbine 122 rotates and, therewith, the turbine shaft 124 rotates, the thrust bearing 136 supports the axial load received by the turbine 122 and transmitted to the thrust bearing 136 via the extended shaft portion 139 while facilitating the low-friction rotational movement of the turbine 122.

[0035] The valve 100 further includes a generator 142. In one example, the generator 142 has a stator and a rotor (not shown). The stator can include a wire winding wound around the body of the stator (e.g., a laminated stack). The rotor is disposed within the stator and the generator 142 can include magnets attached to the rotor in the annular space between the stator and the rotor. The rotor can have a rotor shaft 144 extending within the valve 100.

[0036] The rotor shaft 144 can be coupled to the turbine shaft 124, so that when the turbine shaft 124 rotates, the rotor shaft 144 rotates therewith. As an example, the valve 100 can include a connector 146 configured to couple the rotor shaft 144 to the turbine shaft 124. For example, the proximal end 147 of the turbine shaft 124 can have a hexagonal outer surface, and the connector 146 can have a corresponding hexagonal inner surface that is attached to the hexagonal outer surface of the proximal end 147 of the turbine shaft 124. In this way, when the turbine shaft 124 rotates, the connector 146 rotates therewith. Also, the rotor shaft 144 can be press-fitted (press-fit) into the connector 146, so that the connector 146 is coupled to the rotor shaft 144.

[0037] In one example, the connector 146 can have a hole 148. The rotor shaft 144 can be deformed and a tool can be inserted through the hole 148 so that the rotor shaft 144 is securely coupled to the connector 146. Thus, when the connector 146 rotates with the turbine shaft 124, the rotor shaft 144 (and the rotor of the generator 142) rotates therewith.

[0038] The valve 100 can further include an adapter 150 that couples the generator 142 to the housing 102. For example, the adapter 150 can be cylindrical and hollow. The adapter 150 is screwed (passed) onto the inner surface of the housing 102 via a thread 152. The adapter 150 can have a plurality of threaded holes such as threaded holes 154, and the generator 142 can have a plurality of corresponding threaded holes such as threaded holes 156. Therefore, by attaching screws through the plurality of threaded holes of the adapter 150 and each threaded hole of the generator 142, the generator 142 can be coupled to the adapter 150, and the adapter 150 is coupled to the housing 102 via the thread 152.

[0039] The seal carrier 130 and the seal support member 132 abut (adjacent) against the distal end of the adapter 150, and the adapter 150 is screwed into the housing 102 and thus is stationary. In this way, the seal carrier 130, the seal support member 132, and the spring cap 128 also remain stationary.

[0040] In one example, the valve 100 can be used as a check valve, and the check valve allows fluid flow from the first port 116 to the second port 118 and blocks fluid flow from the second port 118 to the first port 116. In this example, the first port 116 can be fluidly coupled to a fluid source (e.g., a chamber of a hydraulic actuator, an accumulator, a pump, etc.), and the second port 118 can be fluidly coupled to a fluid reservoir (a liquid container).

[0041] In particular, in addition to the closed state shown in FIG. 1, the valve 100 is configured to operate in at least two operating modes. In the first operating mode, the valve 100 allows fluid to flow from the first port 116 through the turbine 122 and then through the main flow intersection holes 119A, 119B of the second port 118. In the second operating mode, the valve 100 allows a portion of the fluid (a portion of the fluid) to flow from the first port 116 through the turbine 122 and then through the main flow intersection holes 119A, 119B of the second port 118, and allows another portion of the fluid (another portion of the fluid) to bypass the turbine 122 and flow directly from the first port 116 to the second port 118 via the bypass flow intersection holes 120A, 120B.

[0042] The fluid at the first port 116 applies a fluid force to the spool 114 in the proximal direction against the spring 127, and the spring 127 applies a biasing force to the spool 114 in the distal direction. Unless the pressure level of the fluid at the first port 116 is sufficient to overcome the biasing force of the spring 127, the spring 127 maintains the spool 114 seated against the seat member 110 at the seat 115.

[0043] As a simplified example, assume that spring 127 is a spring of 100 pounds per square inch (psi), and assume that the pressure level at the second port 118 is zero psi. As long as the pressure level at the first port 116 is less than 100 psi, the spool 114 can remain seated. When the pressure level at the first port 116 reaches 100 psi, the spool 114 can move in the proximal direction.

[0044] When the spool 114 moves in the proximal direction, the spring 127 is compressed and its biasing force increases. The spool 114 can move in the proximal direction until a specific axial position is reached where a force balance is achieved between the forces acting on the spool 114. In the first operating mode, the spool 114 moves away from the seat 115, enabling the flow of fluid between the spool 114 and the seat member 110. However, the spool 114 remains blocking the bypass flow intersection holes 120A, 120B.

[0045] FIG. 4 shows a side cross-sectional view of a valve 100 operating in a first mode that allows fluid to flow from a first port 116 to a second port 118 with fluid flowing through a turbine 122 according to an exemplary implementation. As shown in FIG. 4, the spool 114 moves an axial distance sufficient for the distal end of the spool 114 to move away from the seat member 110, thereby forming an annular flow-through region (flow passage region) 400, while the bypass flow intersection holes 120A, 120B remain blocked by the spool 114.

[0046] As a result, the fluid at the first port 116 flows through the through holes 107, 108 of the nose piece 106 and then through the stator 112, which can create a vortex or spin in the flow and direct a fluid jet through the annular flow-through region 400 towards the turbine 122. In particular, the stator 112 can create a flow having a radial velocity component such that the fluid jet strikes the turbine 122 at an angle that improves the efficiency of the turbine 122.

[0047] When the spool 114 is unseated and separated from the seat portion 115, and the annular flow region 400 begins to open and fluid can flow through it, the annular flow region 400 operates as an orifice of the flow rate limiting means (throttle), so a pressure drop occurs in the annular flow region 400. In other words, the pressure level upstream of the annular flow region 400 (e.g., the outlet of the stator 112) is higher than the pressure level at the turbine 122 downstream of the annular flow region 400.

[0048] Based on Bernoulli's principle, such a pressure difference in the annular flow region 400 accelerates the fluid through the annular flow region 400. In other words, the velocity of the fluid substantially increases when flowing through the annular flow region 400. As an example for illustration, when the pressure drop in the annular flow region 400 is 100 psi, the velocity of the fluid passing through the annular flow region 400 can reach 15 meters per second. Therefore, the fluid discharged from the annular flow region 400 flows downstream and hits the turbine 122 at such a high speed.

[0049] Therefore, even when the fluid flow rate is small when the spool 114 starts to move and separate from the seat portion 115, the fluid hits the turbine 122 at a high speed, and the turbine 122 overcomes its inertia and friction and rotates. Then, the fluid flowing through the turbine 122 can pass through the spool intersection holes 121A, 121B and then through the main flow intersection holes 119A, 119B of the second port 118.

[0050] When the fluid flows through the turbine 122, a pressure drop occurs there. The product of the pressure drop at the turbine 122 and the flow rate of the fluid passing through the valve 100 represents the power (work amount) that can be recovered via the generator 142.

[0051] In particular, when the turbine 122 rotates, the turbine shaft 124 rotates with it, and in so doing, the rotor shaft 144 of the rotor of the generator 142 rotates. When the rotor rotates within the stator of the generator 142 together with the magnets coupled thereto, a current is generated in the wire windings of the stator (assuming an electrical load or resistance is electrically connected to the generator 142). Thus, power is generated by the generator 142 as fluid passes through the valve 100. In other exemplary implementations, different types of generators, such as generators without magnets, may be used.

[0052] The electrical load connected to the generator 142 can be made equal to the torque applied to the turbine 122 when fluid passes through the turbine 122. In the absence of an electrical load connected to the generator 142, the turbine 122 can rotate freely without torque.

[0053] The power recovered can be made equal to the torque of the turbine 122 multiplied by the rotational speed of the turbine 122, assuming no losses (e.g., frictional losses). The power recovered can also be made equal to the pressure drop across the turbine 122 multiplied by the flow rate of the fluid passing through it.

[0054] In some applications, the valve 100 may be placed in the hydraulic line of a machine where the expected amount of fluid flow (flow rate) may exceed the capacity of the valve 100. When such an excessive fluid flow occurs, the pressure level at the first port 116 rises and the pressure drop across the valve 100 increases, which may not be desirable. Thus, the valve 100 is configured to have a bypass flow path to divert the excessive flow away from the turbine 122 and limit the pressure drop across the valve 100.

[0055] FIG. 5 shows a side cross-sectional view of the valve of FIG. 1 operating in a second mode that allows fluid to flow from the first port 116 to the second port 118 with a portion of the fluid flowing through the turbine 122 and another portion bypassing the turbine 122. When an excessive fluid flow rate occurs at the first port 116, the pressure level at the first port 116 may begin to rise. As a result, the fluid force acting on the spool 114 increases and may move the spool 114 farther proximally as compared to FIG. 4, as shown in FIG. 5.

[0056] At such an axial position of the spool 114 shown in FIG. 5, the bypass flow cross holes 120A, 120B are not blocked by the spool 114. Rather, the bypass flow cross holes 120A, 120B are exposed, forming a bypass flow region (flow-through region) 500. Accordingly, a portion of the fluid flows from the first port 116 through the through holes 107, 108, the stator 112, the annular flow region 400, the turbine 122, the spool cross holes 121A, 121B, and the main flow cross holes 119A, 119B of the second port 118, and another portion of the fluid flows from the first port 116 through the through holes 107, 108, the stator 112, the bypass flow region 500, and through the bypass flow cross holes 120A, 120B of the second port 118. In other words, a portion of the fluid flows through the turbine 122 and another portion of the fluid bypasses the turbine 122 and flows directly to the second port 118.

[0057] As a result of such an additional bypass flow path being open directly from the first port 116 to the second port 118, the increase in the pressure level at the first port 116 due to excessive flow is limited. Accordingly, the bypass flow cross holes 120A, 120B allow the valve 100 to be used in a hydraulic machine fluid line where higher flow rates are expected without causing an unduly large pressure drop in the valve 100. For example, the pressure drop across the valve 100 can be limited to about 150 psi.

[0058] In the case of such a configuration, the pressure drop in the turbine 122 is designed not to exceed a specific level. In this way, the turbine 122 and the generator 142 are protected from excessive torque and speed. Furthermore, such a configuration of the valve 100 can reliably recover a specific range of power, and by doing so, it is possible to facilitate the configuration of the generator that handles such a range.

[0059] The recovered power can be used for several purposes. For example, it can be used to charge the battery of a vehicle in which the valve 100 is used (such as a construction machine like a wheel loader or an excavator). In another example, the power can be used to operate other components. For example, it can be used to supply an electrical signal or power to the solenoids of solenoid valves and sensors. This can be particularly beneficial when such valves are located far from the power source and when wires and cables extend over long distances, which may compromise the reliability of the system and increase its complexity. The power recovered by the valve 100, which can be placed near the solenoid valve or sensor instead of using wires that extend over long distances, can be used to power the solenoid valve or sensor. In another example, when the power of the machine stops (e.g., the battery charge runs out), the fluid passing through the valve 100 generates power, and that power can supply power to or operate other components to put the machine's implements in a safe state or move them to a safe position.

[0060] FIG. 6 shows a hydraulic system 600 according to an exemplary implementation. The hydraulic system 600 includes a valve 100 represented by symbols. The main flow path (the flow of fluid from the first port 116 to the second port 118 through the turbine 122) is represented by a spring-loaded check valve 602, and the bypass flow path (the direct flow from the first port 116 to the second port 118 that does not flow through the turbine 122) is represented by a bypass valve portion 604.

[0061] Hydraulic system 600 includes a fluid source 606, such as a pump, an accumulator, or another part of the hydraulic system. Hydraulic system 600 also includes a fluid reservoir 608 that can store fluid at a low pressure (e.g., 0 to 70 psi). The second port 118 of valve 100 is fluidly coupled to fluid reservoir 608.

[0062] Hydraulic system 600 includes a hydraulic actuator 610. Hydraulic actuator 610 includes a cylinder 612 and an actuator piston 614 slidably received within cylinder 612. Actuator piston 614 includes a piston head 616 and a piston rod 618 extending from piston head 616 along the longitudinal central axis of cylinder 612. Piston head 616 divides the inner space of cylinder 612 into a first chamber 620 and a second chamber 622. As an example, a hydraulic cylinder actuator is used herein. Other types of actuators (e.g., hydraulic motors) or other hydraulic devices (hydraulic consumers) can be used.

[0063] Hydraulic system 600 includes a direction control valve 624 that directs fluid to and from hydraulic actuator 610. In one example, direction control valve 624 can include four ports, namely, an inlet port fluidly coupled to source 606, a return port fluidly coupled to the first port 116 of valve 100, a first valve working port fluidly coupled to the first chamber 620 of hydraulic actuator 610, and a second valve working port fluidly coupled to the second chamber 622.

[0064] In one example, the directional control valve 624 can be a spool-type valve having a spool that is axially movable within the bore of the valve body of the directional control valve 624. In that example, the spool can be biased to a neutral position by two springs on both sides of the spool, as indicated by the symbols in FIG. 6. In the exemplary implementation of FIG. 6, in such a neutral position, the two valve work ports can be fluidly coupled to the first port 116 of the valve 100. In other examples, the spool can block all ports in the neutral position.

[0065] Furthermore, although the directional control valve 624 is shown as a single valve, in other exemplary implementations, the directional control valve 624 can comprise two separate valves, each valve independently controlling the flow of fluid to each chamber of the hydraulic actuator 610. Accordingly, any valve assembly or valve configuration that performs the operation of the directional control valve 624 is contemplated herein.

[0066] The directional control valve 624 can be electrically actuated. For example, the directional control valve 624 can have a first solenoid 626 and a second solenoid 628 that move the spool within the directional control valve 624 when energized.

[0067] The hydraulic system 600 further includes a controller 630. The controller 630 can include one or more processors or microprocessors and can include data storage (e.g., memory, temporary computer-readable medium, non-temporary computer-readable medium, etc.). The data storage can store therein instructions that cause the controller 630 to perform the operations described herein when executed by one or more processors of the controller 630. The signal lines to and from the controller 630 are shown as dashed lines in FIG. 6. The signal lines connect the controller 630 to the first solenoid 626. Note that the signal lines connecting the controller 630 to the second solenoid 628 are not shown so as not to make the drawing visually cluttered.

[0068] The controller 630 can receive input information or an input (input) including an input command for operating the hydraulic actuator 610. In response, the controller 630 provides electrical signals to various components of the hydraulic system 600, such as the first solenoid 626 and the second solenoid 628.

[0069] For example, the controller 630 can receive a command or input information that requests the actuator piston 614 to be extended (e.g., moved to the right in FIG. 6). In response, the controller 630 actuates the first solenoid 626. In this way, fluid is supplied from the source 606 to the inlet port of the direction control valve 624, and the direction control valve 624 directs the fluid to the first valve work port and then through the fluid line 632 to the first chamber 620 to extend (advance) the actuator piston 614. The fluid discharged from the second chamber 622 flows through the fluid line 634 to the second valve work port of the direction control valve 624, and the direction control valve 624 directs the fluid to the return port. The fluid discharged from the return port flows to the first port 116 of the valve 100.

[0070] If the pressure level at the first port 116 is sufficient to overcome the spring 127, the spool 114 of the valve 100 moves as previously described with respect to FIG. 4, and the main flow path opens to allow fluid flow through the spring-utilizing check valve 602 and the turbine 122, thereby enabling the generator 142 to generate electrical power, which is effectively used in the hydraulic system 600 as previously described (e.g., charging the battery, or operating the first solenoid 626 or the second solenoid 628 or some other electrically actuated component not shown in the hydraulic system 600). Then, the fluid flows to the second port 118 and then to the fluid reservoir 608.

[0071] If the flow rate of the fluid discharged from the second chamber 622 exceeds the capacity of the valve 100, the pressure level at the first port 116 rises, causing the spool 114 to move further as previously described with respect to FIG. 5, and opening a bypass flow path through the bypass valve portion 604 (i.e., the spool 114 moves to a position where the bypass flow cross holes 120A, 120B are exposed, allowing fluid flow therethrough). Then, such bypass fluid flows directly to the second port 118.

[0072] To retract the actuator piston 614, the controller 630 can send a signal to the second solenoid 628 of the direction control valve 624. In this way, the fluid from the supply source 606 can be directed to the second chamber 622, and the fluid discharged from the first chamber 620 can be directed to pass through the valve 100, and the valve 100 operates based on the flow rate of the fluid discharged from the first chamber 620 and the pressure level at the first port 116 as previously described.

[0073] The configuration of the hydraulic system 600 is a simplified example for illustration. Other system configurations, components, types of direction control valves, etc. can be used.

[0074] FIG. 7 is a flowchart of a method 700 for operating a valve according to an exemplary implementation. The method 700 can be used, for example, to operate the valve 100.

[0075] Method 700 can include one or more operations, functions, or actions represented by one or more of blocks 702-708. Although those blocks are shown in a sequential order, they can be performed in parallel and / or in an order different from that described herein. Also, depending on the desired implementation, various blocks can be combined into fewer blocks, divided into additional blocks, and / or removed. With respect to this and other processes and methods disclosed herein, it should be understood that the flowchart depicts the functions and operations of one possible implementation of the example. Within the scope of the examples of the present disclosure, alternative implementations are included, in which, as would be understood by one of ordinary skill in the art, functions can be performed in an order other than that shown or discussed, including substantially simultaneously or in a reverse order, depending on the relevant functions.

[0076] In block 702, method 700 includes operating valve 100 in a closed state where spool 114 seats on seat member 110 to block the flow of fluid from first port 116 to second port 118, the fluid at first port 116 applies a fluid force to spool 114 in the proximal direction, and spring 127 applies a biasing force to spool 114 in the distal direction toward seat member 110.

[0077] In block 704, method 700 includes opening a main flow path that allows the flow of fluid from first port 116 to a second port through a flow area (e.g., annular flow area 400) formed between spool 114 and seat member 110 by moving spool 114 in the proximal direction away from seat member 110 as the fluid force overcomes the biasing force.

[0078] In block 706, method 700 includes rotating turbine 122 coupled to generator 142 such that the fluid flowing through the main flow path rotates turbine 122 and generator 142 generates power.

[0079] At block 708, method 700 includes opening a bypass flow path that moves spool 114 further distally in response to an increase in the pressure level of the fluid at first port 116, enabling a portion of the fluid to bypass turbine 122 and flow directly from first port 116 to second port 118.

[0080] Method 700 can further include other steps described herein.

[0081] The foregoing detailed description has described various features and operations of the disclosed system with reference to the accompanying figures. The illustrative implementations described herein are not meant to be limiting. Certain aspects of the disclosed system can be arranged and combined in a wide variety of different configurations not all contemplated herein.

[0082] Furthermore, unless the context indicates otherwise, the features shown in each figure may be used in combination with each other. Thus, the figures should be viewed schematically as aspects of one or more overall implementations, understanding that not all features illustrated are required for each implementation.

[0083] Additionally, any listing of elements, blocks, or steps in this specification or the claims is for ease of understanding. Accordingly, such listings should not be construed as indicating that those elements, blocks, or steps are essential to a particular mechanism or that they are required or suggested to be performed in a particular order.

[0084] Furthermore, the device or system can be used or configured to perform the functions shown in the figures. In some examples, the components of the device and / or system can be configured to perform their functions such that the components are actually configured and constructed (using hardware and / or software) to enable such performance. In other examples, the components of the device and / or system can be adapted to perform the functions, capable of performing the functions, or arranged to be suitable for performing the functions, such as when operating in a particular mode.

[0085] The terms "substantially" or "about" mean that it is not necessary to achieve the described features, parameters, or values exactly, but that deviations or variations can occur, for example, due to tolerances, measurement errors, limits of measurement accuracy, and other factors known to those skilled in the art, by an amount that does not prevent the effect intended to be provided by that feature.

[0086] The mechanisms described herein are for illustrative purposes only. Thus, those skilled in the art will understand that other mechanisms and other elements (such as machines, interfaces, operations, sequences, and groupings of operations, etc.) can be used instead, and that some elements can be omitted together depending on the desired results. Furthermore, many of the described elements are functional entities that can be implemented as separate or distributed components or in combination with other components, in any suitable combination and location.

[0087] Although various aspects and implementations have been disclosed herein, other aspects and implementations will be apparent to those skilled in the art. The various aspects and implementations disclosed herein are for illustrative purposes and not intended to be limiting, and the true scope is shown by the appended claims, along with the full scope of equivalents to which those claims are entitled. Also, the technical terms used herein are for the purpose of describing a particular implementation only and are not intended to be limiting.

[0088] Accordingly, an embodiment of the present disclosure can relate to one of the exemplary embodiments (EEE: enumerated example embodiment) in the enumerated form described below.

[0089] EEE1 is a valve comprising: a seat member; a spool configured to seat on the seat member when the valve is in a closed state to block the flow of fluid from a first port to a second port, wherein the fluid at the first port applies a fluid force to the spool in the proximal direction; a spring applying a biasing force to the spool in the distal direction toward the seat member, wherein when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling the flow of fluid from the first port to the second port through a flow region formed between the spool and the seat member; a turbine configured to rotate when the fluid flowing through the flow region flows downstream through the turbine, and attached to a turbine shaft configured to rotate with the turbine; and a generator coupled to the turbine shaft such that the generator generates electric power when the turbine shaft rotates with the turbine.

[0090] EEE2 is the valve according to EEE1, wherein when the pressure level of the fluid at the first port increases, the spool moves further in the proximal direction, thereby enabling a first portion of the fluid to flow through the flow region and the turbine, and enabling a second portion of the fluid to bypass the turbine and flow directly from the first port to the second port.

[0091] EEE3 is the valve according to EEE2, further comprising a sleeve having a longitudinally cylindrical cavity, wherein the spool is disposed within the cylindrical cavity and is axially movable, and the second port comprises a first set of main flow intersection holes formed in the sleeve and a second set of bypass flow intersection holes formed in the sleeve, wherein a first portion of the fluid flowing through the turbine flows to the second port through the first set of main flow intersection holes, and a second portion of the fluid bypassing the turbine flows to the second port through the second set of bypass flow intersection holes.

[0092] EEE4 further includes a nose piece coupled to the distal end of the sleeve, the first port includes a plurality of through holes formed in the nose piece, and the seat member is coupled to the nose piece, which is the valve described in EEE3.

[0093] EEE5 is the valve according to any one of EEE3 - 4, wherein the spool includes a plurality of spool intersection holes, and a first portion of the fluid flowing through the turbine flows through the plurality of spool intersection holes and then through a first set of main flow intersection holes of the sleeve.

[0094] EEE6 is the valve according to any one of EEE1 - 5, further including a stator disposed upstream of the turbine and the flow region, and the stator is configured to direct the fluid to impinge on the turbine at an angle.

[0095] EEE7 is the valve according to any one of EEE1 - 6, further including a radial bearing at least partially mounted on the turbine shaft within the seat member, and the radial bearing is configured to support the turbine shaft within the seat member.

[0096] EEE8 is the valve according to any one of EEE1 - 7, further including a thrust bearing that supports the turbine shaft against axial loads and facilitates the rotation of the turbine shaft with the turbine.

[0097] EEE9 is the valve according to any one of EEE1 - 8, wherein the generator includes a rotor shaft coupled to the turbine shaft such that when the turbine shaft rotates, the rotor shaft of the generator rotates therewith.

[0098] EEE10 is the valve according to EEE9, further including a connector that couples the turbine shaft to the rotor shaft, and when the turbine shaft rotates, the connector rotates, thereby causing the rotor shaft to rotate therewith.

[0099] EEE11 further includes a housing and an adapter coupled to the housing, and is the valve according to any one of EEE1 to 10, wherein a generator is coupled to the adapter.

[0100] EEE12 is a hydraulic system, comprising: a hydraulic actuator having a first chamber and a second chamber; a fluid supply source; a fluid reservoir; a direction control valve having an inlet port fluidly coupled to the fluid supply source, a first work port fluidly coupled to the first chamber of the hydraulic actuator, a second work port fluidly coupled to the second chamber of the hydraulic actuator, and a return port; a valve, the valve comprising: a first port fluidly coupled to the return port of the direction control valve and a second port fluidly coupled to the fluid reservoir; a seat member; a spool configured to seat on the seat member when the valve is in a closed state to block the flow of fluid from the first port to the second port, wherein the fluid at the first port applies a fluid force to the spool in the proximal direction; a spring applying a biasing force to the spool in the distal direction toward the seat member, wherein when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling the flow of fluid from the first port to the second port through a flow region formed between the spool and the seat member; a turbine configured to rotate when the fluid flowing through the flow region flows downstream through the turbine, and is attached to a turbine shaft configured to rotate with the turbine; and a generator coupled to the turbine shaft such that when the turbine shaft rotates with the turbine when the fluid discharged from the return port flows through the valve to the fluid reservoir, the generator generates electric power.

[0101] EEE13 is the hydraulic system according to EEE12, in which when the pressure level of the fluid at the first port rises, the spool moves further in the proximal direction, thereby enabling the first part of the fluid to flow through the flow region and the turbine, and enabling the second part of the fluid to bypass the turbine and flow directly from the first port to the second port.

[0102] EEE14 is the hydraulic system according to EEE13, in which the valve further includes a sleeve having a longitudinal cylindrical cavity, a spool is disposed in the cylindrical cavity and is axially movable, the second port includes a first set of main flow intersection holes formed in the sleeve and a second set of bypass flow intersection holes formed in the sleeve, the first part of the fluid flowing through the turbine flows to the second port through the first set of main flow intersection holes, and the second part of the fluid bypassing the turbine flows to the second port through the second set of bypass flow intersection holes.

[0103] EEE15 is the hydraulic system according to any one of EEE12 - 14, in which the valve further includes a stator disposed upstream of the turbine and the flow region, and the stator is configured to direct the fluid so as to impinge on the turbine at an angle.

[0104] EEE16 is the hydraulic system according to any one of EEE12 - 15, in which the valve further includes a radial bearing that is at least partially attached to the turbine shaft within a seat member and is configured to support the turbine shaft within the seat member, and a thrust bearing that supports the turbine shaft against axial loads and facilitates the rotation of the turbine shaft with the turbine.

[0105] EEE17 is a hydraulic system according to any one of EEE12 - 16, in which the generator includes a rotor shaft coupled to the turbine shaft such that when the turbine shaft rotates, the rotor shaft of the generator rotates with it, the valve further includes a connector that couples the turbine shaft to the rotor shaft, and when the turbine shaft rotates, the connector rotates, thereby causing the rotor shaft to rotate with it.

[0106] EEE18 is a hydraulic system according to any one of EEE12 - 17, in which the valve includes a housing and an adapter coupled to the housing, and the generator is coupled to the adapter.

[0107] EEE19 includes operating the valve in a closed state where the spool seats on the seat member to block the flow of fluid from the first port to the second port, fluid at the first port applies a fluid force to the spool in the proximal direction, and the spring applies a biasing force to the spool in the distal direction towards the seat member; opening a main flow path that allows the flow of fluid from the first port to the second port through a flow area formed between the spool and the seat member by overcoming the biasing force with the fluid force to move the spool in the proximal direction away from the seat member; rotating a turbine coupled to the generator such that when the turbine rotates, the generator generates electricity as the fluid flows through the main flow path; and opening a bypass flow path that allows a portion of the fluid to bypass the turbine and flow directly from the first port to the second port by moving the spool further in the proximal direction as the pressure level of the fluid at the first port increases.

[0108] EEE20, in which the valve comprises a sleeve having a longitudinally cylindrical cavity, within which a spool is disposed and is axially movable; the second port comprises a first set of main flow intersection holes and a second set of bypass flow intersection holes formed in the sleeve; enabling the flow of fluid from the first port to the second port via the main flow path includes enabling fluid to flow to the second port via the first set of main flow intersection holes; enabling a portion of the fluid to flow directly from the first port to the second port through the bypass flow path includes enabling fluid to flow to the second port via the second set of bypass flow intersection holes; is the method according to EEE19. Furthermore, the claims at the time of filing were as follows. [Claim 1] A valve, comprising: a seat member; a spool configured to seat on the seat member when the valve is in a closed state and block the flow of fluid from a first port to a second port, wherein fluid at the first port applies a fluid force to the spool in a proximal direction; the spool; a spring that applies a biasing force to the spool in a distal direction toward the seat member, wherein when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling fluid to flow from the first port to the second port through a flow-through region formed between the spool and the seat member; the spring; a turbine configured to rotate when fluid flowing through the flow-through region flows downstream through the turbine; the turbine; a generator; and wherein the turbine is attached to a turbine shaft configured to rotate with the turbine, the generator is coupled to the turbine shaft such that when the turbine shaft rotates with the turbine, the generator generates electric power. A valve. [Claim 2] The valve according to claim 1, wherein as the pressure level of the fluid at the first port increases, the spool moves further in the proximal direction, thereby enabling a first portion of the fluid to flow through the flow-through region and the turbine, and enabling a second portion of the fluid to bypass the turbine and flow directly from the first port to the second port. [Claim 3] The valve according to claim 2, further comprising a sleeve having a longitudinally extending cylindrical cavity, wherein the spool is disposed within the cylindrical cavity and is axially movable, the second port comprises a first set of main flow intersection holes formed in the sleeve and a second set of bypass flow intersection holes formed in the sleeve, the first portion of the fluid flowing through the turbine flows to the second port through the first set of main flow intersection holes, and the second portion of the fluid bypassing the turbine flows to the second port through the second set of bypass flow intersection holes. [Claim 4] The valve according to claim 3, further comprising a nose piece coupled to the distal end of the sleeve. The first port includes a plurality of through holes formed in the nose piece, and the seat member is coupled to the nose piece. The valve according to claim 3. [Claim 5] The spool includes a plurality of spool cross holes. The first portion of the fluid flowing through the turbine flows through the plurality of spool cross holes and then through the first set of main flow cross holes of the sleeve. The valve according to claim 3. [Claim 6] Further comprising a stator disposed upstream of the turbine and upstream of the flow region. The stator is configured to direct the fluid to impinge on the turbine at an angle. The valve according to claim 1. [Claim 7] Further comprising a radial bearing at least partially mounted on the turbine shaft within the seat member. The radial bearing is configured to support the turbine shaft within the seat member. The valve according to claim 1. [Claim 8] Further comprising a thrust bearing for supporting the turbine shaft against axial loads. The thrust bearing facilitates rotation of the turbine shaft with the turbine. The valve according to claim 1. [Claim 9] The generator includes a rotor shaft, and the rotor shaft of the generator is coupled to the turbine shaft such that the rotor shaft of the generator rotates with the turbine shaft when the turbine shaft rotates. The valve according to claim 1. [Claim 10] Further comprising a connector for coupling the turbine shaft to the rotor shaft. When the turbine shaft rotates, the connector rotates, thereby causing the rotor shaft to rotate with the connector. The valve according to claim 9. [Claim 11] A housing, An adapter coupled to the housing, Further comprising, The generator is coupled to the adapter. The valve according to claim 1. [Claim 12] A hydraulic system, A hydraulic actuator having a first chamber and a second chamber, A fluid supply source, A fluid reservoir, An inlet port fluidly coupled to the fluid supply source, a first work port fluidly coupled to the first chamber of the hydraulic actuator, a second work port fluidly coupled to the second chamber of the hydraulic actuator, and a return port. A direction control valve having, A valve, Comprising. The valve is, a first port fluidly coupled to the return port of the direction control valve, and a second port fluidly coupled to the fluid reservoir, a seat member, a spool configured to seat on the seat member when the valve is in a closed state to block the flow of fluid from the first port to the second port, wherein fluid in the first port applies a fluid force to the spool in the proximal direction, the spool, a spring that applies a biasing force to the spool in a distal direction toward the seat member, and when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling the flow of fluid from the first port to the second port through a flow passage region formed between the spool and the seat member, the spring, a turbine configured to rotate when fluid flowing through the flow passage region flows downstream through the turbine, the turbine, a generator, and includes, the turbine is attached to a turbine shaft configured to rotate with the turbine, the generator is coupled to the turbine shaft such that the generator generates electric power when the turbine shaft rotates with the turbine when fluid discharged from the return port flows through the valve to the fluid reservoir, a hydraulic system. [Claim 13] When the pressure level of the fluid in the first port increases, the spool moves further distally in the proximal direction, thereby enabling a first portion of the fluid to flow through the flow passage region and the turbine, and enabling a second portion of the fluid to bypass the turbine and flow directly from the first port to the second port, the hydraulic system according to claim 12. [Claim 14] The valve further includes a sleeve having a longitudinally cylindrical cavity, and the spool is disposed in the cylindrical cavity and is axially movable, the second port includes a first set of main flow intersection holes formed in the sleeve and a second set of bypass flow intersection holes formed in the sleeve, the first portion of the fluid flowing through the turbine flows to the second port through the first set of main flow intersection holes, The second portion of the fluid bypassing the turbine flows to the second port via the second set of bypass flow intersection holes, the hydraulic system according to claim 13. [Claim 15] The valve further comprises a stator disposed upstream of the turbine and upstream of the flow region, The stator is configured to direct the fluid to impinge on the turbine at an angle, the hydraulic system according to claim 12. [Claim 16] The valve, A radial bearing at least partially mounted to the turbine shaft within the seat member, A thrust bearing supporting the turbine shaft against axial loads, Further comprising, The radial bearing is configured to support the turbine shaft within the seat member, The thrust bearing facilitates rotation of the turbine shaft with the turbine, the hydraulic system according to claim 12. [Claim 17] The generator comprises a rotor shaft, and the rotor shaft of the generator is coupled to the turbine shaft such that the rotor shaft of the generator rotates with the turbine shaft when the turbine shaft rotates, The valve further comprises a connector coupling the turbine shaft to the rotor shaft, When the turbine shaft rotates, the connector rotates, whereby the rotor shaft rotates with the connector, the hydraulic system according to claim 12. [Claim 18] The valve, A housing, An adapter coupled to the housing, Further comprising, The generator is coupled to the adapter, the hydraulic system according to claim 12. [Claim 19] Operating the valve in a closed state where the spool seats on the seat member to block fluid flow from the first port to the second port, fluid at the first port applies a fluid force to the spool in the proximal direction, and a spring applies a biasing force to the spool in the distal direction toward the seat member, Overcoming the biasing force by the fluid force to move the spool in the proximal direction away from the seat member to open a main flow path allowing fluid flow from the first port to the second port through a flow region formed between the spool and the seat member, causing a fluid flowing through the main flow path to rotate a turbine coupled to the generator such that the generator generates electric power when the turbine rotates; opening a bypass flow path that allows a portion of the fluid to bypass the turbine and flow directly from the first port to the second port by moving the spool further distally by an increase in the pressure level of the fluid at the first port; A method comprising: [Claim 20] The valve includes a sleeve having a longitudinal cylindrical cavity, and the spool is disposed within the cylindrical cavity and is axially movable; The second port includes a first set of main flow intersection holes and a second set of bypass flow intersection holes formed in the sleeve; Enabling fluid to flow from the first port to the second port via the main flow path includes enabling fluid to flow to the second port via the first set of main flow intersection holes; The method according to claim 19, wherein enabling a portion of the fluid to flow directly from the first port to the second port through the bypass flow path includes enabling fluid to flow to the second port via the second set of bypass flow intersection holes.

Claims

1. A valve, comprising: a seat member; a spool configured to seat on the seat member when the valve is in a closed state and block the flow of fluid from a first port to a second port, wherein fluid at the first port applies a fluid force to the spool in the proximal direction; the spool; a spring that applies a biasing force to the spool in a distal direction toward the seat member, wherein when the fluid force overcomes the biasing force, the spool moves in the proximal direction away from the seat member, thereby enabling fluid to flow from the first port to the second port through a flow passage area formed between the spool and the seat member; the spring; a turbine configured to rotate when fluid flowing through the flow passage area flows downstream through the turbine; the turbine; a radial bearing; a generator; The valve further comprising: The turbine is attached to a turbine shaft configured to rotate with the turbine; The radial bearing is at least partially attached to the turbine shaft within the seat member; The radial bearing is configured to support the turbine shaft within the seat member; The generator is coupled to the turbine shaft such that the generator generates electrical power when the turbine shaft rotates with the turbine.

2. The valve according to claim 1, wherein an increase in the pressure level of the fluid at the first port causes the spool to move further in the proximal direction, thereby enabling a first portion of the fluid to flow through the flow passage area and the turbine and enabling a second portion of the fluid to bypass the turbine and flow directly from the first port to the second port.

3. The valve according to claim 2, further comprising a sleeve having a longitudinally extending cylindrical cavity, wherein the spool is disposed within the cylindrical cavity and is axially movable; The second port comprises a first set of main flow intersection holes formed in the sleeve and a second set of bypass flow intersection holes formed in the sleeve; The first portion of the fluid flowing through the turbine flows to the second port through the first set of main flow intersection holes; The second portion of the fluid bypassing the turbine flows to the second port through the second set of bypass flow intersection holes.

4. further comprising a nose piece coupled to the distal end of the sleeve, wherein the first port comprises a plurality of through holes formed in the nose piece, and the seat member is coupled to the nose piece, the valve according to claim 3.

5. wherein the spool comprises a plurality of spool cross holes, wherein the first portion of the fluid flowing through the turbine flows through the plurality of spool cross holes and then through the first set of main flow cross holes of the sleeve, the valve according to claim 3.

6. further comprising a stator disposed upstream of the turbine and upstream of the flow region, wherein the stator is configured to direct the fluid to impinge on the turbine at an angle, the valve according to claim 1.

7. further comprising a thrust bearing for supporting the turbine shaft against axial loads, wherein the thrust bearing facilitates rotation of the turbine shaft with the turbine, the valve according to claim 1.

8. wherein the generator comprises a rotor shaft, and the rotor shaft of the generator is coupled to the turbine shaft such that the rotor shaft of the generator rotates with the turbine shaft when the turbine shaft rotates, the valve according to claim 1.

9. further comprising a connector for coupling the turbine shaft to the rotor shaft, wherein the connector rotates when the turbine shaft rotates, whereby the rotor shaft rotates with the connector, the valve according to claim 8.

10. a housing, an adapter coupled to the housing, further comprising, wherein the generator is coupled to the adapter, the valve according to claim 1.

11. a hydraulic system, a hydraulic actuator having a first chamber and a second chamber, a fluid supply source, a fluid reservoir, a direction control valve having an inlet port fluidly coupled to the fluid supply source, a first work port fluidly coupled to the first chamber of the hydraulic actuator, a second work port fluidly coupled to the second chamber of the hydraulic actuator, and a return port, the valve according to any one of claims 1 to 10, comprising. The first port of the valve is fluidly coupled to the return port of the direction control valve, and the second port of the valve is fluidly coupled to the fluid reservoir. A hydraulic system in which the generator generates electric power when the fluid discharged from the return port of the direction control valve flows through the valve to the fluid reservoir. **Claim 12** Operating the valve in a closed state where the spool seats on the seat member to block the flow of fluid from the first port to the second port, the fluid in the first port applies a fluid force to the spool in the proximal direction, and the spring applies a biasing force to the spool in the distal direction toward the seat member. Overcoming the biasing force by the fluid force to move the spool in the proximal direction away from the seat member to open a main flow path that allows the flow of fluid from the first port to the second port through a flow region formed between the spool and the seat member. Rotating the turbine coupled to the generator such that the generator generates electric power when the turbine rotates as the fluid flows through the main flow path. Increasing the pressure level of the fluid in the first port to move the spool further in the proximal direction to open a bypass flow path that allows a portion of the fluid to bypass the turbine and flow directly from the first port to the second port. A method comprising the above. **Claim 13** The valve includes a sleeve having a longitudinally cylindrical cavity, and the spool is disposed within the cylindrical cavity and is axially movable. The second port includes a first set of main flow intersection holes and a second set of bypass flow intersection holes formed in the sleeve. Enabling the flow of fluid from the first port to the second port through the main flow path includes enabling the fluid to flow to the second port through the first set of main flow intersection holes. The method according to claim 12, wherein enabling a portion of the fluid to flow directly from the first port to the second port through the bypass flow path includes enabling the fluid to flow to the second port through the second set of bypass flow intersection holes.

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