Rotary shear valve

Abstract

A rotor for a directional control valve includes a rotor body defining a sealing surface, a circumferential side surface, and a rod that receives a rotation input to rotate the rotor about an axis. A first opening is formed in the sealing surface and defines a first perimeter. The first opening is positioned to move along a path of rotation upon rotation of the rotor body and has a first notch extending along the path of rotation from the first perimeter toward a centerline of the rotor body, the centerline being perpendicular to the axis. A second opening is formed in the sealing surface and defines a second perimeter. The second opening is positioned to move along the rotation path when the rotor body rotates, and has a second notch extending from the second periphery toward the centerline of the rotor body and along the rotation path.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 508,250, filed on June 14, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the technical field of valves, and more particularly, to systems and methods for directional control valves. Background Art

[0004] Hydraulic tools and pumps may include one or more control valves, such as directional control valves, to connect and disconnect fluid pathways (including portions of a hydraulic circuit). Some control valves may include a rotary shear seal valve having a rotor. Summary of the invention

[0005] Examples of the present invention provide systems and methods for directional control valves. The directional control valve may include a rotary valve, such as a rotary shear seal valve. Some examples of rotary shear seal valves include a four-way three-position valve.

[0006] According to one aspect of the present disclosure, a rotor for a directional control valve may include a rotor body defining a sealing surface, a circumferential side surface, and a rod. The rod may receive a rotational input to rotate the rotor about an axis. The rotor may also include a first opening formed in the sealing surface and defining a first periphery. The first opening is positioned to move along a rotational path when the rotor body rotates. The first opening has a first recess, and the first recess extends along the rotational path from the first periphery toward the center line of the rotor body, and the center line is perpendicular to the axis. The rotor may also include a second opening formed in the sealing surface and defining a second periphery. The second opening may be positioned to move along the rotational path when the rotor body rotates. The second opening has a second recess extending from the second periphery toward the center line of the rotor body and along the rotational path.

[0007] In some examples, each of the first perimeter and the second perimeter has a circular shape, and each of the first notch and the second notch may be formed as a triangular portion.

[0008] In some examples, the triangular portion may define an arcuate base and an apex opposite the arcuate base. The rotation path may bisect the arcuate base and intersect the apex.

[0009] In some examples, the rotor may further include a third opening formed in the sealing surface and defining a third perimeter. The third perimeter may define a circular shape having an opening area that is smaller than the opening area of ​​the first opening. The rotor may further include a fourth opening formed in the sealing surface that defines a fourth perimeter. The fourth perimeter may define a circular geometry and a surface area that is smaller than the first perimeter of the first opening.

[0010] In some examples, the first opening and the second opening can be in fluid communication with each other.The third opening and the fourth opening can be in fluid communication with each other.

[0011] In some examples, the first and second notches may be shaped to promote a linear decrease in pressure as the rotor rotates.

[0012] In some examples, the directional control valve can rotate between three positions. The first position can fluidly couple the first opening to the pressure source and the second opening to the tank. The second position can fluidly couple the first opening to the tank and the second opening to the pressure source. The third position can be a position where the first opening and the second opening are not fluidly coupled to the tank or the pressure source.

[0013] In some examples, the first position may correspond to an extension of the piston rod within the cylinder of the piston-cylinder assembly. The second position may correspond to a retraction of the piston rod within the cylinder of the piston-cylinder assembly.

[0014] According to another aspect of the present disclosure, a shear seal control valve may include a valve body defining a first port and a second port, and a rotor rotatably received in the valve body, the rotor having a plurality of openings formed in a mating surface of the rotor. The plurality of openings may be arranged to allow the first port and the second port to selectively couple when the rotor rotates in the valve body. The plurality of openings may include a first opening and a second opening, each of the first opening and the second opening defining a perimeter having a partially circular portion and a triangular portion. The respective triangular portions may define recesses of the respective first opening and the second opening.

[0015] In some examples, the plurality of openings may include third and fourth openings that define a surface area that is smaller than a perimeter of the first and second openings.

[0016] In some examples, the first opening and the second opening can be in fluid communication with each other.The third opening and the fourth opening can be in fluid communication with each other.

[0017] In some examples, the notch may provide a linear pressure reduction in hydraulic pressure as the rotor rotates from the first position to the second position.

[0018] In some examples, in the first position, the first opening may be coupled to the pressure source and the second opening may be coupled to the tank.

[0019] In some examples, in the second position, the first opening may be coupled to the canister and the second opening may be coupled to the pressure source.

[0020] According to another aspect of the present disclosure, a method of operating a piston via a rotary shear seal valve may include rotating a rotor to a first position. A pressure source may be fluidly coupled to a first opening. A second opening may be fluidly coupled to a tank. The piston may extend within a cylinder of a piston-cylinder assembly, which causes operation on a workpiece. The rotor may be rotated to a second position. A first recess of the first opening may be fluidly coupled to the tank. A second recess of the second opening may be fluidly coupled to a pressure source. The piston may be retracted into the cylinder of the piston-cylinder assembly.

[0021] In some examples, the rotor can rotate in a first rotational direction to reach the first position. The rotor can rotate in a second rotational direction to reach the second position. The first rotational direction can be opposite to the second rotational direction.

[0022] In some examples, the method may further include rotating the rotor to a third position.The first opening, the second opening, the pressure source, and the tank may be fluidly decoupled.

[0023] In some examples, the third position may be a neutral position between the first position and the second position that blocks fluid flow through the first opening and the second opening.

[0024] In some examples, the first notch and the second notch may be located on a rotational path of the rotor that increases flow metering.

[0025] In some examples, the first notch and the second notch can be triangular-shaped. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present invention and, together with the detailed description, serve to explain the principles of embodiments of the present invention:

[0027] Figure 1 is a bottom isometric view of a rotor for a rotary valve according to aspects of the present disclosure.

[0028] Figure 2 is a side isometric view of a rotary shear valve including a rotor and a valve disc.

[0029] Figure 3 is a side isometric view of a rotary valve including a valve disk and a first port and a second port.

[0030] Figure 4 yes Figure 3 Top isometric view of a rotary valve.

[0031] Figure 5 is a side isometric view of a rotary valve.

[0032] Fig. 6A is a bottom view of the rotor of the rotary valve in a first position.

[0033] Figure 6B yes Fig. 6A Bottom view of the rotary valve in the middle position.

[0034] Figure 6C yes Fig. 6A Bottom view of the rotary valve in the second position.

[0035] Figure 7 is an equidistant cross section of the rotary valve in the first position.

[0036] Figure 8 It is a bottom view of the rotary valve in the middle position.

[0037] Fig. 9 is an enlarged view of the notch on the rotor of a rotary valve.

[0038] Fig.10 yes Figure 1 Schematic diagram of the surface of the rotor.

[0039] Fig.11 Is from Figure 8 A schematic diagram of an enlarged view of the port.

[0040] Fig.12 yes Figure 1 Schematic diagram of the surface of a rotor showing exemplary internal passages of the rotor.

[0041] Fig.13A is a schematic diagram of the valve in a first position.

[0042] Fig. 13B yes Fig.13A Schematic diagram of the valve in the middle position.

[0043] Fig. 13C yes Fig.13A Schematic diagram of the valve in the second position.

[0044] Fig.14A is a schematic diagram of the valve in a first position and in communication with the piston.

[0045] Fig. 14B yes Fig.14A Schematic diagram of the valve being in the second position and connected to the piston. DETAILED DESCRIPTION

[0046] The following discussion is presented to enable those skilled in the art to make and use embodiments of the present invention. Various modifications to the illustrated embodiments will be apparent to those skilled in the art, and the general principles herein may be applied to other embodiments and applications without departing from embodiments of the present invention. Therefore, embodiments of the present invention are not intended to be limited to the illustrated embodiments, but to conform to the widest scope consistent with the principles and features disclosed herein. The following detailed description will be read with reference to the accompanying drawings, in which the same elements in different drawings have the same reference numerals. The accompanying drawings are not necessarily drawn to scale, depicting selected embodiments, and are not intended to limit the scope of embodiments of the present invention. Those skilled in the art will recognize that the examples provided herein have many useful alternatives and fall within the scope of embodiments of the present invention.

[0047] Before explaining any embodiment of the present invention in detail, it should be understood that the present invention is not limited in its application to the details of the construction and arrangement of the components set forth in the following description or shown in the accompanying drawings. The present invention can have other embodiments and can be practiced or executed in various ways. Moreover, it should be understood that the words and terms used herein are for descriptive purposes and should not be considered as limiting. For example, "including", "comprising" or "having" and variations thereof used herein are meant to cover the items listed thereafter and their equivalents and additional items.

[0048] A pump (including a hydraulic tool having a pump) may include one or more valves to control the flow of fluid within the tool. Hydraulic tools can be used to perform various operations, including crimping, cutting, and extrusion work. Some hydraulic tools may include valves, such as shear valves. For example, a shear valve may be found in or near a sprocket assembly of a pump of a hydraulic tool. In some cases, the shear valve may be connected to a camshaft of a rotary drive system. In other cases, the rotor of a rotary shear sealing valve may be connected to a shaft operatively coupled to the rotor to rotate the rotor and move the valve to different positions. The shaft may be rotated by a motor, manually, or a combination thereof.

[0049] Directional control valve (directional control valve, DCV) is a device capable of controlling the direction of a fluid. DCV can connect or disconnect parts of a hydraulic circuit. Some DCVs, including the DCV described herein, can be configured as four-way and three-position rotary shear seal valves. Typically, a rotary shear seal valve can include a rotor with a limited layout for port communication. By rotating the rotor, the communication between the ports can be changed. The rotary shear seal valve also includes a shear seal disk, which contacts the rotor base to seal the port. The four-way and three-position DCV has four passages (e.g., ports), including a first port, a second port, a third port, and a fourth port. For example, the first port can be a pump port (P) connected to a pump, the second port can be a first working port (e.g., port A (A)) connected to a working function (e.g., a first end of a hydraulic actuator), the third port can be a third working port (e.g., port B (B)) connected to a working function (e.g., a second end of a hydraulic actuator), and the fourth port can be a tank port (T) connected to a tank. The valve can be moved between three positions to selectively connect four ports. In one particular example, a first position (e.g., position "A") can connect a pump port to a first working port, and can connect a second working port to a tank port. A second position (e.g., position "B") can connect a pump port to a second working port, and can connect a first working port to a tank port. A third position (e.g., a neutral position or position "N") can connect a pump port to a tank port while blocking the first working port and the second working port. In this regard, the first position and the second position can be working positions that enable working operations to be performed, while the third position is an intermediate position that allows hydraulic fluid to be discharged directly to the tank. Thus, when the rotor is switched from the intermediate position to the A or B position, the fluid port in the valve body will align with the fluid port in the rotor to allow fluid to flow to the selected port.

[0050] Typically, some hydraulic tools can be used to perform cutting or crimping on a workpiece (e.g., a cable, connector, or other object). Typically, a hydraulic tool includes a cylinder and piston configuration, wherein the piston is configured to extend and retract within the cylinder, and thereby move a jaw or any other device coupled to the piston to perform a task (crimping, cutting, lifting, retracting, etc.). In some hydraulic tools, the hydraulic circuit may include a two-position (or multi-position) valve. In a three-position valve, the fluid may be directed to extend the piston, which corresponds to the first valve position. In the second position, the fluid may be directed to retract the piston. And in the third or intermediate position, the fluid may be prevented from entering or leaving the piston.

[0051] Some embodiments of the present invention provide a rotor for a rotary shear seal valve. The rotor may generally be configured as a disk defining a rotor surface (e.g., a flat rotor surface). The rotor may include a plurality of outlet (or inlet) openings formed in the flat rotor surface. In addition, the rotor may include one or more auxiliary control paths, turns, or recesses that communicate with a respective one of the plurality of outlet ports.

[0052] In use, a flow path turn or notch formed at the periphery of the outlet port can improve flow metering while reducing loads during lifting applications. Typically, lifting applications can include extending a piston (e.g., a hydraulic piston) to overcome a force (e.g., gravity) to move a load. The notch can define a triangular (or other) geometric shape that can help a user control backflow to achieve a greater range of motion during rotor rotation. The notch can advantageously facilitate backflow control and help manage flow metering. An embodiment of the present invention provides a rotor having a notch or flow path turn at a first port outlet and a second port outlet (or other) on a rotor of a rotary shear seal valve.

[0053] Typically, during valve rotation, the notch in the rotor crosses the periphery of the port (i.e., the periphery of the port formed in the flat surface), which creates an opening area (e.g., a flow path turning portion) that allows flow from the pressurized port to the reservoir (e.g., a tank). As the rotation angle increases, the flow rate can increase due to the increase in the opening area formed at the periphery of the notch / port. Therefore, depending on the angular position of the notch relative to the periphery of the flat surface of the port, the user can accurately control the opening area for flow by controlling the angle of the rotor. Without the notch, the angle for controlling the opening area is minimal and difficult to accurately manipulate or adjust. That is, by providing the notch, the rate of change of the opening area per degree of rotation at the notch increases compared to the main part of the opening. As a result, when only the notch is exposed to form a portion of the flow path, a larger rotation is required to increase the opening area, which allows the opening area to be more accurately controlled by the controller during flow metering, and also enhances flow stability.

[0054] Figure 1-14 shows various aspects of an exemplary valve 102 that allow for improved flow control, such as providing flow metering, particularly at low flow rates. The valve 102 is configured as a rotary shear valve 102 that can be used to control work operations in power tools, particularly hydraulic power tools (e.g., crimpers or cutters), and other applications for controlling fluid flow. The rotary shear valve 102 generally includes a valve body 126 having a base 140 and a valve cover 138 connected together and defining a plurality of ports 142. As shown, the valve 102 is configured as a four-way, three-position valve having a first port 142b, a second port 142a, a third port 142c, and a fourth port 142d. In this case, the first port 142b is a first working port coupled to a work function, the second port 142 is a second working port coupled to a work function, the third port 142c is a pump port coupled to a pump, and the fourth port is a tank port configured to be coupled to a tank. Typically, the fluid flows from the third port 142c and may flow into the first port 142b, the second port 142a, or to the fourth port 142d depending on the position of the rotor 100, as will be discussed further below. In other applications, more or fewer ports may be provided, and the ports may be coupled to other external components to meet the needs of a particular application. To this end, each port 142 may be provided with a connector (e.g., a threaded connection, a quick-connect fitting, or another type of connection interface) to facilitate connection to an external component.

[0055] The valve is operable between a plurality of positions to selectively connect the ports to provide flow control. To connect the ports, the valve includes a control member that is movable to selectively connect the ports. In the example shown, the valve 102 includes a control member that is configured as a rotor 100 rotatably retained in a valve body 126. That is, the rotor 100 is rotatable within the valve body 126 to selectively connect the ports 142, and will be described in more detail below. Figure 1As shown, the rotor 100 includes a rotor body 104 defining a mating surface 106 (e.g., a sealing surface), a circumferential side surface 108, and a rod 110. Generally, the rod 110 can provide rotational control of the rotor 100 and include an input receiving portion 112. The input receiving portion 112 can receive a manual or motorized input to rotate the rotor body 104. The rotor 100 can also define a plurality of openings 114 to selectively connect to ports 142 in the valve body 126. For example, a first opening 114a, a second opening 114b, a third opening 114c, and a fourth opening 114d can be formed in the mating surface 106 and arranged along the rotational path 116 of the rotor 100, so that when the rotor 100 rotates, the opening 114 can be positioned to provide a connection between the ports 142, as described in more detail below. In addition, (auxiliary) openings 114e, 114f can also be provided in the mating surface 106. In the illustrated embodiment, opening 114e may be formed at a central position relative to mating surface 106 and rotational path 116, and opening 114f may be configured as a through hole extending through the disk portion of the rotor in an axial direction (eg, along the rotor's rotational axis).

[0056] In some cases, the openings 114 form an internal passageway within the rotor body 104. In some cases, the openings 114 on the mating surface can be connected to openings on another surface to allow the openings 114 to connect with one or more of the ports 142. For example, with continued reference to Figure 1 , the rotor body 104 may also include openings 120a, 120b disposed on the circumferential surface 108 of the rotor body 104. In the example shown, the opening 120a may be in fluid communication with each of the openings 114a and 114b, and the opening 120b may be in fluid communication with each of the openings 114c and 114d. However, other configurations are also possible. In addition, one or more of the openings 120 may include a plug 128a. For example, the opening 120a may be plugged so that the fluid passage only visibly exists between the first port 114a and the second port 114b formed in the mating surface 106.

[0057] Each of the openings 114a-f may define a corresponding opening perimeter 122 that defines an opening to a corresponding port 142. For example, the first and second openings 114a, 114b define corresponding first and second perimeters 122a, 122b. As will be further described below with reference to FIGS. 6 and 7, the first and second perimeters 122a, 122b may define corresponding notches 124a, 124b. The notches 124a, 124b typically form triangular notches in the mating surface 106 that are in fluid communication with each of the first and second openings 114a, 114b. That is, for example, if the outer flat surface is planarly aligned and abuts against the mating surface 106 of the rotor 100 in the axial direction 118 (e.g., flush with the mating surface 106), discrete paths will be formed between the first notch 124a, the first opening 114a, the second opening 114b, and the second notch 124b. In other examples, notches of different shapes or sizes may be provided to achieve desired flow characteristics.

[0058] Now refer to Figure 2 , shows an exemplary assembly of a rotor 100 having openings 120a, 120b on the circumferential side surface 108. As described above, the openings 120a, 120b may be in fluid communication with the plurality of openings 114 on the mating surface 106 of the rotor 100. Figure 2 The assembly also includes a set of disks 132 and a set of springs 134, which are positioned adjacent to the mating surfaces. In the illustration, three disks 132 and three springs 134 are shown in the disk set 132 and spring set 134, respectively; however, other configurations are possible. In addition, the valve 102 may include first and second valve ports 142a, 142b (e.g., ports A and B) that are connected from the base 140 ( Figure 3 ) extend laterally outward and are fluidically coupled to the plurality of openings 114 of the rotor 100. Figure 3 As shown, the disc 132 is received in the base 140 and is biased by a spring 134 (e.g., or another type of resilient member, such as a bushing) to contact the mating surface 106 of the rotor 100, thereby providing a seal between the plurality of openings 114 and the valve ports 142a, 142b. More specifically, as shown in FIG. Figure 4 As shown, the disk 132 is aligned with the first valve port 142b (e.g., port A), the second valve port 142a (e.g., port B), and the third port 142c (e.g., port P). In some cases, the fourth port 142d (e.g., port T) may also include a disk and a spring. This alignment allows fluid to flow through each port while preventing fluid from leaking between each port and the mating surface 106 of the rotor 100.

[0059] refer to Figure 5, the assembly structure of the rotary shear valve 102 shows the rotary shear valve 102 further including the rotor 100, the valve cover 138, the base 140 and the sensor 144. The sensor 144 can be used to control the position of the rotor 100. The sensor 144 can include a sensor arm 146, which is coupled to the rotor 100 and is in fluid communication with the plurality of openings 114. The sensor 144 can be a ZMID (zinc metal ion detector) sensor or a Hall sensor, however other sensors are also possible (e.g., a contact switch, a position sensor, etc.).

[0060] In use, as the valve 102 (i.e., the rotor 100) rotates between a plurality of positions, the valve 102 connects the plurality of openings 114 of the rotor 100 to the ports 142 of the base 140 to direct flow between the fourth port 142d, the third port 142c, and various combinations of the first port 142a and the second port 142b.

[0061] Fig. 6A -C shows an exemplary orientation of a rotor (e.g., rotor 100) rotating between different positions. For example, in Fig. 6A , a first position is shown. In the first position, pressure port P (third port 142c) is in fluid communication with port A (first port 142b), and tank T (fourth port 142d) is in fluid communication with port B (second port 142a). As valve 102 rotates, it connects the cavities to direct flow accordingly. Fig. 6A Rotate to the direction shown Figure 6B In the third position shown, the valve moves to a middle or neutral position in which neither the tank T nor the pressure P is in communication with either port A or B. When the rotor 100 rotates again, the pressure port P can be in fluid communication with port B, and the tank T can be in fluid communication with port B. Fig. 6A As shown in FIG. 1-C, plugs 128a, 128b may be provided to block the flow of fluid through the openings 120a, 120b provided on the circumferential surface 108 at each position to further regulate the flow of fluid, control the fluid pressure, and prevent fluid leakage. In particular, as shown in FIG. Figure 6C As shown, plug 128a covers opening 120a when fluid flows to tank T and plug 128b covers opening 120b when fluid flows from pressure port P to port B, and thus, plugs 128a, 128b can further provide a measure for gradually releasing fluid pressure. Conversely, plug 128a partially covers opening 120a when fluid flows into port A, and plug 128b covers opening 120b when fluid flows from port B into tank T, and thus, plugs 128a, 128b can allow a stable pressure to build up.

[0062] Figure 7 Shows Fig. 6A, wherein the pressure or third port 142c (P) is in fluid communication with the first valve port 142b (A). As a result, fluid can flow from the pressure source to the first port 142b (A), such as Figure 7 As shown by the arrow in the reference Figure 8 and Fig. 9 When the rotor 100 begins to rotate toward the middle (eg, neutral) position, the fluid diversion path or notch 124 allows bypass flow to the cavity in the valve cover 138, which is connected to the tank. For example, the notch 124 allows the fluid to flow through the sealing surface formed by the disk 132.

[0063] The notch 124 is located on the rotational path 116, which advantageously allows a wider range of rotation angles in which the notch 124 provides flow metering. Therefore, the user can move the rotor 100 to a certain angle and slowly control and meter the flow. Having the notch 124 that provides controlled flow allows flow metering at higher pressures and reduces or prevents sudden losses of load or pressure drop. Generally, the notch allows fluid or pressure to be slowly released to the tank and can provide more finely tuned flow metering than a rotor that has no notch and is only slowly rotated. For example, the notch can provide a linear pressure reduction in the system as the rotor rotates.

[0064] Fig.10 A schematic bottom view of the rotor 100 and a plurality of openings 114a-f is shown. Each of the first, second, third, and fourth openings 114a-d is disposed along a rotational path 116. The rotational path 116 defines a circumference around which the first, second, third, and fourth openings 114a-d are positioned and travel as the rotor 100 rotates, and the rotational path generally corresponds to the complementary positioning of the disk 132 engaging the mating surface 106 at the corresponding opening 114. In the illustrated embodiment, there are four openings 114a-d disposed around the rotational path 116. However, in other embodiments, additional ports or fewer ports may be formed in the mating surface 106 around the rotational path 116 or otherwise.

[0065] As briefly described, each of the openings 114 can define a corresponding perimeter 122. The perimeters 122c, 122d of the openings 114c, 114d define a generally circular geometry. In contrast, the perimeters 122a, 122d define a partially circular geometry with cutouts defining corresponding recesses 124a, 124b. In this case, the recess 124 has a triangular geometry; however, other geometries are also possible. The recesses 124a, 124b increase the opening area of ​​the corresponding perimeters 122a, 122b of the openings 114a, 114b (e.g., compared to the perimeters 122c, 122d of the openings 114c, 114d). In general, the recesses can improve the performance of the valve in lifting applications. In particular, the recesses 124a, 124b can facilitate a controlled reduction in active load by allowing finer control of the flow rate.

[0066] Fig.11 An enlarged form of the recess 124a is shown. As shown, the perimeter 122a of the opening 114a includes a generally circular portion 148a and a generally triangular portion 150a defining the recess 124a. The triangular portion 150a includes a base 152a defining the same radius of curvature as the circular portion 148a of the perimeter 122a. In some cases, the recess 124 is positioned so that the base 152a is bisected by the rotation path 116. In addition, the triangular portion 150a includes a vertex 154a. The vertex 154a is disposed along the rotation path 116. In some embodiments, the triangular portion 150a can generally define an unequal-sided triangle such that each of the three sides has a different length. However, other geometric shapes are also possible. In addition, it should be understood that, although not shown in detail, the recess 124b can define a similar (although not in the embodiment of the embodiment of the present invention) to the recess 124a. Figure 8 156) features and geometries. Notably, each vertex of the notches 124a, 124b extends along the corresponding perimeter 122a, 122b and the rotational path 116 toward the centerline 156 of the rotor 100. That is, the portion of each perimeter 122a, 122b closest to the centerline 156 is the corresponding vertex (i.e., the vertex 154a for the opening 114a). This arrangement allows the notches to become exposed depending on the direction of rotation of the rotor 100, as may allow flow metering.

[0067] In other embodiments, the perimeter (e.g., perimeters 122a, 122b) may define other geometric shapes that provide a controllable or metered flow when the rotor 100 moves from the high pressure fluid communication position. For example, the perimeter or port shape may define an elliptical or kidney bean shape. Additionally or alternatively, the recess may also include a triangular geometry with curved sides to provide a linear or otherwise controlled flow to the tank or reservoir as the rotor rotates. In general, the perimeter geometries described herein may provide an increased range of rotation of the rotor to meter the flow of high pressure fluid to the tank, for example, during a load reduction event.

[0068] Fig.12 Another schematic bottom view of the rotor 100 is shown. As shown, the first opening 114a and the second opening 114b can be fluidly connected via a first internal passage 160 extending through the rotor body 104. Similarly, the third opening 114c and the fourth opening 114d can be fluidly connected via a second internal passage 162. The internal passages 160, 162 can be configured as holes (e.g., blind holes) formed by drilling (or milling, etc.) through the circumferential side surface 108 of the rotor 100. Depending on the rotor configuration (e.g., the number of locations and paths), additional or fewer ports and passages can be formed in the body 104 of the rotor 100. In addition, one or more of the internal passages 160, 162 can be blocked or opened at the circumferential side surface 108 to provide a port on the circumferential side surface 108 (e.g., Figure 1 openings 120a, 120b).

[0069] Fig.13A -C shows a rotary shear valve, such as valve 102, in three different positions. These positions correspond roughly to Fig. 6A -C. For example, Fig.13A In the embodiment, the first port 142b (A) can be fluidly connected to the third port 142c (eg, a pressure source (P)), and the second port 142a (B) can be fluidly connected to the fourth port 142d (eg, a tank (T)). Fig. 13B The valve is shown in an intermediate or neutral position, wherein neither the first or second ports 142a, 142b (A and B) are connected to the fourth or third ports 142d, 142c (eg, a tank or pressure source). Fig. 13C The valve 102 is shown in a second position, wherein the first port 142b (A) is in fluid communication with the fourth port 142d (eg, a tank (T)) and the second port 142a (B) is in fluid communication with the third port 142c (eg, a pressure source (P)).

[0070] Fig.14A and 14BA schematic diagram of the rotary shear valve 102 and fluid communication with an exemplary piston-cylinder assembly 170 is shown. Fig.14A The valve 102 is shown in a first position corresponding to the extension of the piston rod 172 within the cylinder 174 of the piston-cylinder assembly 170 . Fig. 14B 1 and 2. The valve 102 is shown in a second position, which corresponds to the retraction of the piston rod 172 within the cylinder 174. In some embodiments, when the valve 102 is in a Fig. 14B In the second position shown, the first opening 114a (A) having the notch 124a can communicate with the fluid (e.g., high pressure fluid) discharged from the cylinder 174. The notches 124a, 124b can improve flow metering while reducing load during lifting applications, and can help the user control the return flow during the rotation of the rotor 100 for a wider range of motion.

[0071] Thus, embodiments of the disclosed invention may provide systems and methods for advancing and retracting a piston of a hydraulic tool via a rotary shear seal valve. The previous description of the disclosed embodiments is provided to enable a person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but should be consistent with the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A rotor for a directional control valve, the rotor comprising: a rotor body defining a sealing surface, a circumferential side surface, and a stem receiving a rotational input to rotate the rotor about an axis; a first opening formed in the sealing surface and defining a first perimeter, the first opening being positioned to move along a rotational path as the rotor body rotates, and the first opening having a first notch extending from the first perimeter toward a centerline of the rotor body and along the rotational path, the centerline being perpendicular to the axis; as well as A second opening is formed in the sealing surface and defines a second periphery, the second opening is positioned to move along the rotational path when the rotor body rotates, and the second opening has a second notch extending from the second periphery toward the centerline of the rotor body and along the rotational path.

2. The rotor according to claim 1, wherein: Each of the first perimeter and the second perimeter has a circular shape, and each of the first recess and the second recess is formed as a triangular portion.

3. The rotor according to claim 2, wherein: The triangular portion defines an arcuate base and an apex opposite the arcuate base, and wherein the rotational path bisects the arcuate base and intersects the apex.

4. The rotor according to claim 1, further comprising: a third opening formed in the sealing surface and defining a third perimeter defining a circular shape and having an opening area that is smaller than an opening area of ​​the first opening; as well as A fourth opening is formed in the sealing surface and defines a fourth perimeter defining a circular geometry and a surface area that is smaller than the first perimeter of the first opening.

5. The rotor according to claim 4, wherein: The first opening and the second opening are in fluid communication with each other, and the third opening and the fourth opening are in fluid communication with each other.

6. The rotor according to claim 1, wherein: The first notch and the second notch are shaped to facilitate a linear reduction in pressure as the rotor rotates.

7. The rotor according to claim 1, wherein: The directional control valve can rotate between three positions as follows: a first position fluidly coupling the first opening with a pressure source and fluidly coupling the second opening with a tank; a second position fluidly coupling the first opening with the tank and fluidly coupling the second opening with the pressure source; as well as A third position in which the first opening and the second opening are not fluidly coupled to the tank or the pressure source.

8. The rotor according to claim 7, wherein: The first position corresponds to an extension of the piston rod within a cylinder of a piston-cylinder assembly, and the second position corresponds to a retraction of the piston rod within the cylinder of the piston-cylinder assembly.

9. A shear seal control valve, comprising: a valve body defining a first port and a second port; as well as a rotor rotatably received in the valve body and having a plurality of openings formed in a mating surface of the rotor, the plurality of openings being arranged to allow selective coupling of the first port and the second port as the rotor rotates in the valve body, The plurality of openings includes a first opening and a second opening, each of the first opening and the second opening defining a perimeter having a partially circular portion and a triangular portion, the respective triangular portion defining a recess of the respective first opening and the second opening.

10. The shear seal control valve according to claim 9, wherein: The plurality of openings also include third and fourth openings defining a surface area that is smaller than a perimeter of the first and second openings.

11. The shear seal control valve according to claim 10, wherein: The first opening and the second opening are in fluid communication with each other, and the third opening and the fourth opening are in fluid communication with each other.

12. The shear seal control valve according to claim 9, wherein: The notch provides a linear pressure reduction in hydraulic pressure as the rotor rotates from a first position to a second position.

13. The shear seal control valve of claim 12, wherein: In the first position, the first opening is coupled to a pressure source and the second opening is coupled to a tank.

14. The shear seal control valve of claim 13, wherein: In the second position, the first opening is coupled to the tank and the second opening is coupled to the pressure source.

15. A method of operating a piston via a rotary shear seal valve, the method comprising: rotating the rotor to a first position; fluidly coupling a pressure source to the first opening and fluidly coupling the second opening to the tank; extending a piston within a cylinder of a piston-cylinder assembly, which causes operation on a workpiece; rotating the rotor to a second position; fluidly coupling a first recess of the first opening to the tank and fluidly coupling a second recess of the second opening to the pressure source; as well as The piston is retracted into the cylinder of the piston-cylinder assembly.

16. The method according to claim 15, wherein: The rotor rotates in a first rotational direction to reach the first position and rotates in a second rotational direction to reach the second position, the first rotational direction being opposite to the second rotational direction.

17. The method according to claim 15, further comprising: rotating the rotor to a third position; as well as The first opening, the second opening, the pressure source, and the tank are fluidly decoupled.

18. The method according to claim 17, wherein: The third position is a neutral position between the first position and the second position, the neutral position blocking fluid flow through the first opening and the second opening.

19. The method according to claim 15, wherein: The first notch and the second notch are located on a rotational path of the rotor that increases flow metering.

20. The method according to claim 19, wherein: The first notch and the second notch are triangular in shape.

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