Method and system for flow isolation valve arrangement and three-chamber cylinder hydraulic structure

Abstract

Disclosed is a hydraulic circuit including one or more i) linear, or ii) rotary hydraulic actuators having a total number of cylinder chambers, N, M pressure rails, M hydraulic rail ports respectively coupled to the pressure rails, N hydraulic chamber ports respectively coupled to chambers of the one or more actuators, N proportional valves each corresponding to one of the N hydraulic chamber ports, X sets of on / off valves and check valves coupling two or more hydraulic rail ports to respective supply sides of the N proportional valves, Y sets of on / off valves and check valves coupling two or more hydraulic rail ports to respective return sides of the N proportional valves, and a controller configured to operate the N proportional valves and associated on / off valves in real time to achieve one or more desired functional parameters.

Description

[Technical field]

[0001] <CROSS REFERENCE TO RELATED APPLICATIONS> This patent application is related to and claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 257,537, filed October 19, 2021, entitled "A THREE CHAMBER CYLINDER HYDRAULIC ARCHITECTURE," U.S. Provisional Patent Application No. 63 / 257,540, filed October 19, 2021, entitled "FLOW-ISOLATED VALVE ARRANGEMENT," and U.S. Provisional Patent Application No. 63 / 257,545, filed October 19, 2021, entitled "METHOD AND SYSTEM FOR A FLOW-ISOLATED VALVE ARRANGEMENT," the contents of each of which are incorporated by reference in their entirety into this disclosure.

[0002] <Government Funding Statement> none.

[0003] <Technical field> The present disclosure relates generally to hydraulic architecture, and in particular to a three-chamber cylinder hydraulic architecture that is particularly useful in construction machinery as well as flow-isolated valve arrangements. [Background technology]

[0004] <Background> This section introduces aspects that may be helpful to facilitate a better understanding of the present disclosure. As such, these statements should be read in this light and not understood as admissions about what is or is not prior art.

[0005] Hydraulic systems utilized in heavy machinery are very well known. Early on, simple hydraulic cylinders were used to generate a force to move an object based on the hydraulic pressure in the cylinder and the effective area of ​​the piston moving within the cylinder, creating a load force. A typical cylinder uses two chambers, each with its own effective area, and such a configuration creates a force in each direction. The net force of the resultant of the pressurized fluid acting on both areas of the cylinder is typically referred to as the cylinder load. Traditional applications usually act on the flow rate into / out of one chamber while keeping the remaining chamber at the lowest possible pressure to reduce system losses.

[0006] Although the original concept was quite simple, different hydraulic control architectures have been developed over the years, especially as the number of hydraulic actuators per machine increases. Typically, these architectures use a shared hydraulic power source, such as a hydrostatic pump, and a dedicated control valve for each actuator. The challenges associated with these architectures are twofold: first, controllability of multiple actuators with a single shared hydraulic source, and second, energy efficiency. While different approaches in the prior art have been successful with respect to the first challenge, most circuits currently available on the market still suffer from low efficiency when powering more than one actuator at a time.

[0007] When multiple hydraulic actuators share the same hydraulic supply, the pressure supplied must be slightly higher than the maximum pressure requirement of the system. Any other hydraulic actuators that require lower pressure to achieve a desired load therefore require throttle control to reduce the supply pressure to the desired level, which results in power loss. In this disclosure, the term "hydraulic actuator" refers to either a rotary actuator or a linear actuator. Any system aimed at energy efficiency therefore needs to minimize the pressure difference between the supply system and the respective pressure requirements of multiple actuators sharing the same supply.

[0008] To achieve such a condition, it is possible to 1) increase the number of supply pressure rails so that more than one supply pressure is available, and 2) increase the number of cylinder chambers so that different combinations of connections between chambers and supply rails can be used to minimize throttling requirements and therefore reduce system losses. In short, with more options for combining different chamber areas and pressures, the difference between supply pressure and chamber pressure can be smaller, reducing throttling losses, to achieve the same load (effective cylinder force). As a result, the more combinations (cylinder modes) available, the more efficient the cylinder should be in theory.

[0009] The relationship between the pressure rail and the number of chambers, which achieves a discretized number of possible connections between the pressure rail and the cylinder chambers (modes) for different applications, is governed by the following equation: Number of discrete modes = (number of chambers) 圧力レールの数 These different combinations of connections between the supply pressure and the cylinder chambers are sometimes referred to as discrete force levels available to the actuator.

[0010] One example of such a multi-chamber configuration is provided in U.S. Patent No. 10,704,569 to Sipola et al., which introduced at least a four-chamber actuator utilizing two pressure rails identified as high pressure (HP) and low pressure (LP). As shown in FIG. 1a, each chamber is coupled to each of the pressure rails utilizing a system of parallel valves. That is, each chamber is coupled to both the high pressure rail and the low pressure rail utilizing two separate valves, one between each pressure rail and the chamber. In this case, proportional valves were utilized to synchronize the opening and closing of the valves, but ultimately, non-throttle control was used. Thus, the proportional valves are maintained either fully open or fully closed (except during transient periods) since any partial opening of the valves would introduce the fluid throttling that characterizes throttle control.

[0011] Based on the above formula, in the example shown in Figure 1a, the number of discretized forces is 4 2 and is equal to 16, and FIG. 1b shows a graph of the discretized force per index ranging from 1 to 16. This means that if non-throttled control is used, as described in the '569 patent, only a load force of 16 is achievable, limiting the accuracy of speed tracking, especially at low speeds. This is because any mismatch between the load force and the actual actuator force requirement results in cylinder acceleration. Therefore, if accurate motion control is to be achieved, continuous throttling in at least one of the chambers is required, thus creating a trade-off between control accuracy and efficiency.

[0012] The approaches shown in the '569 patent are typical in the prior art (see, for example, WO 2014081353 A1). However, these approaches have drawbacks. For example, the number of chambers in the cylinder and the number of pressure rails (two in the '569 patent) reduces the number of discretized forces, while a larger number of chambers requires a complex cylinder design. As mentioned above, in the '569 patent, a combination of four chambers and two pressure rails resulted in 16 discretized forces. In the WO 2014081353 A1 publication, a five-chamber actuator could be used with two pressure rails to result in 25 discretized forces. However, in all these iterations, only two pressure rails were used, resulting in an expensive and complex cylinder configuration with a reduced number of discretized forces. Also, including an additional pressure rail in the above-mentioned structure would not be cost-effective since a large number of valves would be required.

[0013] Furthermore, both references refer to the use of non-throttle controls, or a mixture of on / off (or open / close / on / off) and proportional valves, limiting the achievable efficiency and performance of such systems.

[0014] Another aspect to consider is that in these types of constructions, the cylinder controller constantly changes the supply lines connected to each chamber. This means that for a short transient, one valve (i.e., connecting the chamber to the high pressure line) is closing while the other valve (i.e., connecting the same chamber to the low pressure line) is opening. Because these valves are not infinitely fast, both valves are opened for a short period of time, creating a short circuit between the high pressure and low pressure supply lines. This eventually causes significant leakage and reduces system efficiency.

[0015] The short circuit phenomenon described above exists regardless of the use of on / off or proportional valves. The rationale for using proportional valves in the prior art described above is based on the need to synchronize and delay the opening and closing of valves connecting different rails to a given chamber. Such an approach may reduce the impact of this short circuit on the system efficiency. Nevertheless, such a solution cannot eliminate the problem. In addition, such a solution requires a proportional valve with a very short closing time, and since no throttle control was used, the cylinder is still limited to a finite number of available forces. DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0016] Thus, there exists an unmet need for new approaches in hydraulic structures and control methods that can achieve more precise operational control without significant increase in system losses due to throttling control and without increasing the complexity of cylinder design, as well as new method and system approaches that can provide isolated flow between any two pressure rails without shorting when one pressure rail is switched to the other. [Means for solving the problem]

[0017] <Summary> According to one embodiment, a valve arrangement is disclosed that includes M hydraulic rail ports, each configured to be coupled to a pressure rail, N hydraulic chamber ports, each configured to be coupled to a chamber of one or more actuators, and N proportional valves, each corresponding to one of the N hydraulic chamber ports. Each proportional valve includes a rail side coupled to the M hydraulic rail ports and a chamber side coupled to the corresponding hydraulic chamber port. Each rail side of the N proportional valves is divided into a supply side configured to supply hydraulic fluid to the corresponding hydraulic chamber port and a return side configured to receive hydraulic fluid from the corresponding hydraulic chamber port. The valve arrangement further includes X sets of on / off valves and check valves that couple two or more hydraulic rail ports to each of the supply sides of each of the N proportional valves, and Y sets of on / off valves and check valves that couple two or more hydraulic rail ports to each of the return sides of each of the N proportional valves. Selective operation of each of the on / off valves and the proportional valve provides selective pressure or flow to each one of the N hydraulic chamber ports.

[0018] According to one embodiment, in the valve device, X has a maximum number M-1.

[0019] According to one embodiment, in said valve device, X has a minimum number of 1.

[0020] According to one embodiment, in said valve device, Y has a maximum number M-1.

[0021] According to one embodiment, in said valve device, Y has a minimum number of 1.

[0022] According to one embodiment, in the above valve arrangement, the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to selectively define the pressure on the supply side of the proportional valve.

[0023] According to one embodiment, in the above valve arrangement, the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

[0024] According to one embodiment, in the above valve arrangement, the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to selectively define the pressure on the return side of the proportional valve.

[0025] According to one embodiment, in the above valve arrangement, the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

[0026] According to another embodiment, there is also disclosed a hydraulic circuit including one or more i) linear or ii) rotary hydraulic actuators, each having one or more cylinder chambers disposed therein, with a total number of cylinder chambers N, M pressure rails, each with a corresponding pressure, and a valve arrangement. The valve arrangement includes M hydraulic rail ports each configured to be coupled to a pressure rail, N hydraulic chamber ports each configured to be coupled to a chamber of one or more actuators, N proportional valves each corresponding to one of the N hydraulic chamber ports, each proportional valve including a rail side coupled to the M hydraulic rail ports and a chamber side coupled to a corresponding hydraulic chamber port, each rail side of the N proportional valves being divided into a supply side configured to supply hydraulic fluid to the corresponding hydraulic chamber port and a return side configured to receive hydraulic fluid from the corresponding hydraulic chamber port, X sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the supply sides of each of the N proportional valves, and Y sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the return sides of each of the N proportional valves. Selective operation of each of the on / off valves and proportional valves provides a selective pressure or flow to each one of the N hydraulic chamber ports. The hydraulic circuit also includes a controller configured to receive one or more desired functional parameters for the one or more cylinder chambers and, in real time, i) receive data from a plurality of sensors associated with the one or more cylinder chambers, and ii) activate and deactivate the N proportional valves and associated on / off valves to achieve the one or more desired functional parameters.

[0027] According to one embodiment, in said hydraulic circuit, X has a maximum number M-1.

[0028] According to one embodiment, in said hydraulic circuit, X has a minimum number of 1.

[0029] According to one embodiment, in said hydraulic circuit, Y has a maximum number M-1.

[0030] According to one embodiment, in said hydraulic circuit, Y has a minimum number of 1.

[0031] According to one embodiment, in the hydraulic circuit, the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to selectively define the pressure on the supply side of the proportional valve.

[0032] According to one embodiment, in the hydraulic circuit, the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

[0033] According to one embodiment, in the hydraulic circuit, the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to selectively define the pressure on the return side of the proportional valve.

[0034] According to one embodiment, in the hydraulic circuit, the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

[0035] According to one embodiment, in the above hydraulic circuit, each of the M pressure rails is supplied from one or more power sources.

[0036] According to one embodiment, in the hydraulic circuit, the power source is an internal combustion engine.

[0037] According to one embodiment, in the hydraulic circuit, the power source is one or more electric motors.

[0038] According to one embodiment, in the hydraulic circuit, pressure in the pressure rail is maintained at a desired level by one or more hydrostatic pumps, either fixed or variable displacement.

[0039] According to one embodiment, in the hydraulic circuit, real-time measured conditions including pressure, force, torque, position, and velocity are used to regulate the desired pressure level and associated range of variation in the pressure rail.

[0040] According to one embodiment, in said hydraulic circuit, the one or more functional parameters include force.

[0041] According to one embodiment, in the hydraulic circuit, the one or more functional parameters include speed.

[0042] According to one embodiment, in the hydraulic circuit, the one or more functional parameters include position.

[0043] According to one embodiment, in the hydraulic circuit described above, a controller controls the N proportional valves and associated on / off valves based on minimizing the energy loss between the supply side and return side of each of the N proportional valves.

[0044] According to one embodiment, in the hydraulic circuit, the controller utilizes data from multiple sensors associated with one or more cylinder chambers in one or more feedback loops.

[0045] Also disclosed is a hydraulic force generator for use with heavy machinery, comprising a hydraulic actuator having three chambers disposed therein, three hydraulic rails consisting of i) a high pressure rail, ii) a medium pressure rail, and iii) a low pressure rail, and at least 3 NM proportional control hydraulic valves coupled to the hydraulic linear actuator, each chamber being coupled to the N hydraulic rails via a proportional valve, and continuous force control is achieved by proportionally controlling the opening area of ​​each valve, where M is the number of optionally removable valves, and 0≦M≦2. N-2 It is.

[0046] According to one embodiment, in the hydraulic power generator, the N hydraulic rails are supplied from a single power source.

[0047] According to one embodiment, in the hydraulic power generator, the single power source is an internal combustion engine.

[0048] According to one embodiment, in the hydraulic power generating device, the single power source is one or two electric motors powered by a battery pack.

[0049] According to one embodiment, in the hydraulic power generator, each of the N hydraulic rails represents hydraulic power provided by a single hydrostatic pump having an outlet that feeds (or serves) each of the N hydraulic rails via a directional valve.

[0050] According to one embodiment, in the hydraulic power generator, two or more hydrostatic pumps are used to provide hydraulic power to the N hydraulic rails.

[0051] According to one embodiment, in the hydraulic force generator, the hydrostatic pump is based on one of a fixed or variable displacement.

[0052] According to one embodiment, in the above hydraulic force generator, N is 3.

[0053] According to one embodiment, in the above hydraulic force generator, N is 2.

[0054] According to one embodiment, in the hydraulic force generator, real-time measured conditions including pressure, force, position and velocity are used to regulate the desired pressure level and associated range of variation in the pressure rail.

[0055] Also disclosed is a hydraulic control system for use with heavy machinery, comprising a hydraulic actuator having three chambers arranged in a central portion, three hydraulic rails consisting of i) a high pressure rail, ii) a medium pressure rail, and iii) a low pressure rail, and at least 3 NM proportionally controlled hydraulic valves coupled to the hydraulic actuator, each chamber being coupled to N hydraulic rails via a proportional valve, and continuous force control being achieved by proportionally controlling the opening area of ​​each valve, where M is the number of optionally removable valves, and 0≦M≦2. N-2 The hydraulic control device also includes a control unit which serves to adjust the opening of the proportional valve so that a pressure closed-loop control by fluid throttling can be achieved in each one of the multi-chamber cylinder chambers. Such a pressure controller may also be used as an inner-loop of a closed-loop speed or position control.

[0056] According to one embodiment, in the hydraulic control system, the multi-chamber cylinder includes pressure sensors in the hydraulic lines above and downstream of each proportional valve.

[0057] According to one embodiment, in the hydraulic control system, a position or velocity sensor is included so that closed loop position / velocity control can be achieved.

[0058] According to one embodiment, in the hydraulic control system, the N hydraulic rails are supplied from a single power source.

[0059] According to one embodiment, in the above hydraulic control system, the power source is an internal combustion engine.

[0060] According to one embodiment, in the above hydraulic control system, the power source is one or two electric motors powered by a single battery pack.

[0061] According to one embodiment, in the above hydraulic control system, each of the N hydraulic rails represents hydraulic power provided by a single hydrostatic pump having an outlet that supplies (or serves) each of the N hydraulic rails via a directional valve.

[0062] According to one embodiment, in the hydraulic control system, two or more hydrostatic pumps are used to provide hydraulic power to the N hydraulic rails.

[0063] According to one embodiment, in the above hydraulic control system, the hydrostatic pump is based on one of a fixed or variable displacement.

[0064] According to one embodiment, in the above hydraulic control system, N is three.

[0065] According to one embodiment, in the above hydraulic control system, N is two. [Brief description of the drawings]

[0066] <Brief Description of the Drawings> [Figure 1a] FIG. 1a is a schematic diagram of a hydraulic circuit according to the prior art.

[0067] [Figure 1b] FIG. 1b is a graph showing the discretized force numbers according to the hydraulic circuit of FIG. 1a.

[0068] [Diagram 2] FIG. 2 is a schematic diagram of a valve arrangement according to the present disclosure.

[0069] [Figure 3a-c] 3a, 3b and 3c are hydraulic circuits according to the present disclosure.

[0070] [Figure 4] FIG. 4 is a schematic diagram of an embodiment of a valve device according to the present disclosure having two chambers with opposing flow directions.

[0071] [Diagram 5] FIG. 5 is a schematic diagram of an embodiment of a valve device according to the present disclosure in a three chamber system.

[0072] [Figure 6] FIG. 6 is a schematic diagram of a control scheme for the valve arrangement of the present disclosure, according to one embodiment.

[0073] [Figure 7] FIG. 7 is a schematic diagram of a block diagram representing the outer loop control shown in FIG.

[0074] [Figure 8a-b] 8a and 8b depict a single flow chart spread across two pages illustrating the control scheme according to the present disclosure.

[0075] [Figure 9] FIG. 9 is a block diagram of pressure control according to the present disclosure.

[0076] [Figure 10] FIG. 10 is a schematic diagram of a hydraulic system for a heavy equipment system including a linear actuator with three chambers and three pressure rails resulting in 27 discretized force modes.

[0077] [Figure 11] FIG. 11 is a schematic diagram of a control scheme for the hydraulic circuit shown in FIG. 10, according to one embodiment.

[0078] [Figure 12] FIG. 12 is a block diagram of pressure control according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0079] <Detailed Description> For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the principles of the disclosure, it being understood nevertheless that no limitation of the scope of the disclosure is intended thereby.

[0080] In this disclosure, the term "about" can refer to a degree of variation of a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated range limit.

[0081] In this disclosure, the term "substantially" can refer to a degree of variation of a value or range, for example, within 90%, within 95%, or within 99% of a stated value or of the limits of a stated range.

[0082] Provided herein is a novel valve arrangement in hydraulic structures that can provide independent chamber pressure control between any two pressure rails with pressure rail isolated flow without short circuit when one pressure rail is switched to the other pressure rail. Additionally provided herein is a novel method and system approach in hydraulic structures that utilizes the aforementioned novel valve arrangement. To this end, reference is made to FIG. 2, in which a schematic diagram of a valve arrangement 100 according to the present disclosure is shown. In the embodiment shown in FIG. 2 and all other embodiments of the present disclosure, the valve arrangement includes M hydraulic rail ports 1011, 1012, 1013 each configured to be coupled to a pressure rail (in FIG. 2, M=3 including high pressure (HP) 102, medium pressure (MP) 104, and low pressure (LP) 106), N hydraulic chamber ports each configured to be coupled to an actuator chamber, and N or 2N proportional valves 110 (in FIG. 2, N=1). Each proportional valve includes a rail side 112 that can be coupled to up to M hydraulic rail ports and a chamber side that is coupled to a corresponding hydraulic chamber port 108. When N proportional valves are used, each rail side of the N proportional valves is divided into a supply side configured to supply hydraulic fluid to a corresponding hydraulic chamber port and a return side configured to receive hydraulic fluid from the corresponding hydraulic chamber port. It is also possible to use 2N two-way valves, one connecting the chamber to the supply side and the other connecting the chamber to the return side. In addition, the valve device of the present disclosure includes X sets of on-off valves 1201, 1202 and check valves 1221, 1222 (X=2 in FIG. 2) that couple two or more hydraulic rail ports 1011, 1012, 1013 to each of the supply sides 116 of each of the N proportional valves 110. X has a maximum number M-1 (in this case, M=3 and X=2). The minimum value of X is 1. Additionally, the valve gear of the present disclosure includes Y sets of on / off valves 1241, 1242 and check valves 1261, 1262 coupling two or more hydraulic rail ports 1011, 1012, 1013 to each of the return sides 118 of each of the N proportional valves 110 (in FIG. 2, Y=2), with a maximum number M−1. The minimum number for Y is 1.As described below, selective operation of each of the on / off valves and the proportional valve provides accurate and efficient pressure control to each one of the N hydraulic chamber ports.

[0083] Further, the on / off valves 1201, 1202 and the check valves 1221, 1222 on the supply side 116 of each of the N proportional valves 110 cooperate to selectively define a pressure on the supply side 116 of the proportional valve 110. Further, the on / off valves 1201, 1202 and the check valves 1221, 1222 on the supply side 116 of each of the N proportional valves 110 cooperate to prevent fluid flow between the hydraulic rail ports 1011, 1012, 1013 having a first pressure and the hydraulic rail ports 1011, 1012, 1013 having a second pressure, the first pressure being higher than the second pressure. Further, the on / off valves 1241, 1242 and the check valves 1261, 1262 on the return side 118 of each of the N proportional valves 110 cooperate to selectively define a pressure on the return side 118 of the proportional valve 110. Further, the on / off valves 1241, 1242 and check valves 1261, 1262 on the return side 118 of each of the N proportional valves 110 cooperate to prevent fluid flow between the hydraulic rail ports 1011, 1012, 1013 having a first pressure and the hydraulic rail ports 1011, 1012, 1013 having a second pressure, the first pressure being higher than the second pressure.

[0084] As mentioned above, the valve arrangement 100 shown in Fig. 2 is coupled to three pressure rails, namely, high pressure rail 102, medium pressure rail 104, and low pressure rail 106. These three pressure rails are coupled to the actuator chambers via a combination of on / off valves 1201, 1202, 1241, 1242 (shown as 1V2, 1V3, 1V7, and 1V9) and check valves 1221, 1222, 1221, 1222 (shown as 1V4, 1V5, 1V6, and 1V8) and proportional valve 110 (shown as 1V1). In the illustrated embodiment, the inlet port 130 of the 3 / 3 proportional valve 110 (1V1) is coupled to the high pressure rail 102 via on / off valve 1201 (1V2). The same port is also coupled to the medium pressure rail 104 via on / off valve 1202 (1V3) and check valve 1221 (1V4). The inlet port 130 is also coupled to the low pressure rail 106 via a check valve 1221 (1V5). Similarly, the outlet port 132 of the proportional valve 110 (1V1) is coupled to the high pressure rail 102 via a check valve 1261 (1V6), to the medium pressure rail 104 via an on / off valve 1242 (1V9) and a check valve 1262 (1V8), and to the low pressure rail 106 via an on / off valve 1241 (1V7). A pre-loaded check valve 128, identified as 1V10, can be added to avoid cavitation in the chamber. Additionally, a relief valve 130, identified as 1V11, is used as a safety device to limit the maximum pressure in the chamber.

[0085] To better explain the operation of the valve arrangement 100 shown in FIG. 2, the following scenario is provided as an example. Assume that the on / off valve 1202 (1V2) is initially turned on to provide high pressure from the high pressure rail 102 to the proportional valve 110 (1V1). When the supply side 116 wants to change the pressure to medium pressure by coupling the proportional valve 110 (1V1) to the medium pressure rail 104, the on / off valve 1201 (1V2) is deactivated and at the same time, the on / off valve 1202 (1V3) is activated. The short circuit problem mentioned above with respect to the prior art is mitigated by the check valves 1221 (1V4) and 1222 (1V5), and the high pressure fluid from the proportional valve 110 (1V1) is blocked from the medium pressure rail 104 (MP line) and the low pressure rail 106 (LP line) by the check valves 1221 (1V4) and 1222 (1V5), respectively.

[0086] It should be understood that the device 100 shown in FIG. 2 is merely exemplary. The valve device of the present disclosure may include a greater or lesser number of pressure rails. It should also be noted that different valve assemblies may be possible while using the same concept. For example, depending on the application, it may not be necessary to couple both inlet / outlet ports 130 / 132 of the proportional valve 110 (1V1) to all three pressure rails. In this scenario, the number of on / off valves may be reduced. Examples of such circuits are shown in FIGS. 3a, 3b, and 3c, each showing an example hydraulic circuit.

[0087] Figure 3a is similar to Figure 2 in that proportional valve 210 (2V1) is coupled to two on / off valves 220 (2V2) and 224 (2V4). Figure 3b is similar to Figure 2 in that proportional valve 310 (3V1) is coupled to three on / off valves 320 (3V2), 324 (3V4), and 326 (3V7). Figure 3c is similar to Figure 2 in that proportional valve 410 (4V1) is coupled to three on / off valves 420 (4V2), 424 (4V4), and 426 (4V6).

[0088] Similarly, in the case of two chambers with opposite flow directions (i.e., a cylinder with two opposing chambers), the two associated proportional valves coupled to each chamber can share the same set of on / off and check valves, as shown in FIG. 4, which provides a schematic diagram of an embodiment of a valve arrangement according to the present disclosure having two chambers with opposite flow directions.

[0089] In the present disclosure, the valve arrangement 100 of Figure 2, or possible variations thereof within the skill set of one of ordinary skill in the art, is used to control pressure in a linear actuator chamber. It should be emphasized that it is also possible to extend the concept to structures having more than two chambers by replicating the configurations shown in Figures 2 and / or 4 as required for use. An example of a system having multiple chambers is shown in Figure 5, which provides a schematic diagram of an embodiment of a valve arrangement according to the present disclosure in a system having three chambers.

[0090] Referring to Figure 5, assume that the multi-chamber cylinder is extended with chambers A and C expanding and chamber B retracting. The control mechanism responsible for operating the valves is commanded to move proportional valve 6V10 to remain between a center position and a left-most position, connecting the chamber side of the proportional valve to the supply side and allowing flow from the rail to the chamber to control the pressure in each chamber as desired. Similarly, proportional valve 6V15 is maintained between a center position and a right-most position, connecting the chamber side to the return side and allowing flow from the chamber to the rail to control the pressure in each chamber.

[0091] To minimize throttling losses at (or across) valve 6V10, the supervisory controller selects between the available pressure levels on the supply side of the proportional valve and commands the state of on / off valves 6V11 and 6V12. Similarly, valve 6V15 InTo minimize throttling losses, the controller selects between the pressure levels available on the return side and determines the state of the on / off valves 6V17 and 6V19. The set of valves connected to chamber C is controlled similarly to that of chamber A, while the remaining on / off valves 6V7 and 6V9 remain closed.

[0092] During retraction of the cylinder, operation is similar, but in this case proportional valve 6V10 is between the center position and the rightmost position, connecting chamber A to the return side, while proportional valve 6V15 is between the center position and the leftmost position, connecting chamber B to the supply side. The pressure in chamber C is controlled in the same way as chamber A, with its own dedicated valve set. If a fourth chamber is added to the cylinder in the opposite direction to chamber B, it can also share the set of on / off and check valves used to supply proportional valve 6V1.

[0093] The disclosed valve arrangement for controlling pressure in a multi-chamber cylinder offers several advantages over the prior art arrangements discussed above. First, the disclosed valve arrangement avoids any shorting between pressure rails when the valve is switched from one pressure rail to another. At the same time, no complex control mechanisms are required to appropriately delay the valves as discussed above. This simple and elegant structure allows for instant switching between pressure rails (high pressure rail to mid pressure rail, mid pressure rail to low pressure rail, high pressure rail to low pressure rail, mid pressure rail to high pressure rail, and mid pressure rail to low pressure rail) without crosstalk or shorting between the rails, since the proportional valve provides a degree of downstream pressure control, while still providing independent pressure control in each one of the chambers of the multi-chamber cylinder. Thus, by adjusting the proportionality of the valve opening, fine-tune control may be achieved given a choice of supply and return rails. Second, only a single proportional valve is required per chamber, rather than two or sometimes three as in the prior art. This approach offers the added advantage of reducing cost and control complexity.

[0094] According to one embodiment, a control scheme 500 for these three valve devices is shown in Figure 6. Although direct force control is also possible, this example is shown with an additional outer-loop controller 502 that may be used. The outer-loop evaluates the difference between a reference signal and its actual measurement for the state to be controlled. Position (x) or velocity (x') control is achieved by a PID controller that adjusts the reference force command, as shown in Figure 7. The gain K p scales the error to produce a control input proportional to the error in the controlled state (velocity in the illustrated example), while the gain K I and K Dand act on the tracking error integral and derivative, respectively. All three controller components are summed to generate a force command that is sent to the force mode selection algorithm.

[0095] The force mode selection algorithm receives the desired cylinder force, as well as the rail pressure and cylinder velocity. It then selects the state of each on / off valve (u) to minimize energy loss. on / off ) is selected. Diagrams of the algorithm are shown in Figures 8a and 8b. These are two figures that split the algorithm into two pages. For this figure and other figures provided herein, the variables provided herein are defined in Table-1 below. Table 1 - Definitions of variables used in the figures of this disclosure TIFF2024537315000002.tif245169

[0096] For each available mode, the code evaluates the following expression: J mode =J EL +J CE +J I Here, J EL is the penalty for energy loss, while J CE penalizes the control effort required for switching by avoiding frequent switching, I The algorithm penalizes modes that are not feasible under the current operating conditions. For each available mode, the mode In FIG. 8b, the selection of the optimal solution is performed in section 4 (block identified as “4”). Furthermore, for each mode, the pressure p s,A , p s,B , p s,C , and p r,A , p r,B , p r,CWith t defined, mode feasibility can be verified by evaluating the required and achievable pressure differential across the proportional valve, as highlighted in section 2 of the embodiment. In section 3, the time elapsed since the last switch (t sw ) is the target time interval for the next switch (t target ), penalizes mode switching if the time t1 is shorter than t2. Penalties represented by large values ​​(LV1) and (LV2) are used for penalized prohibited modes, thus avoiding their selection, if the constraints or goals are not met.

[0097] The above block receives actuator velocity measurements which are used to estimate the throttling loss requirements in each mode. This is accomplished by evaluating the following equations: J EL =abs(x′ t s ·[F ref -F mode ]) Here, t s is the sampling time of the controller, and F mode is the resulting cylinder output force that would be available if a proportional valve were not used.

[0098] In addition, the algorithm also, as highlighted in Section 1, ref The required pressure in each cylinder chamber is evaluated so that the reference pressure (p ref,i ) is obtained.

[0099] Each cylinder chamber has its own local controller, whose pressure is controlled by feedback control, as shown in Figure 9. These controllers also know the commanded state (u) of the on / off valve so that the controller knows the supply and return pressures of the proportional valve in advance. on / off ) is received. Therefore, hp ), medium pressure rail (p mp), low voltage rail (p lp Based on the pressure level received at the proportional valve and the state of the valve, the pressure evaluation logic block determines the pressure on the supply side of the proportional valve (p s,i ), return side (p r,i ) pressure. In this way, the opening of each proportional valve can be electronically compensated when there is a change in pressure on either the supply or return side of the proportional valve, using a non-linear valve map that estimates the necessary valve command so that a desired flow rate is achieved at a given pressure differential. Such a pressure differential (Δp) is calculated using the measured chamber pressure (p ch,i,meas ) and the supply or return pressure. This is necessary because both the supply and return pressures change depending on the state of the on / off valve. This embodiment also uses a controller gain K to ensure that the reference pressure is tracked. P,i , K I,i and K D,i Based on the value of cmd ) is used as an input to the valve nonlinearity map, which adjusts the flow of each proportional valve (u pv,i ) to output commands.

[0100] Furthermore, a novel approach in hydraulic construction for heavy machinery is presented, which can provide a large number of discretized forces without the need for complex actuator designs. This allows the introduction of small throttle controls for fine control adjustments via proportional valves without significantly increasing system losses and without the need for cylinders with a large number of chambers, which can significantly increase the complexity of the cylinder design and affect its reliability. For this purpose, reference is made to FIG. 10, which is a schematic diagram of a hydraulic device 600 for a heavy machinery system, including an actuator 601 with three chambers and three pressure rails 602, 604, and 606, which provide 27 discretized force levels. Although the hydraulic device 600 of FIG. 10 is shown with one actuator 601, more linear or rotary actuators may be coupled to the same pressure rail. The linear actuator 601 includes three chambers (not individually identified for simplicity) that are independently controlled by a network of proportional valves. Each valve of the network of proportional valves serves to couple a chamber with one of the actuators to a supply rail. Three rails 602, 604, and 606 are provided, each one at a different pressure level. These different pressure rails are generated by power sources such as the one shown in FIG. 10 (internal combustion engine (ICE)) or by other power generation schemes known to those skilled in the art (e.g. electric motors, etc.). The pressure in each rail is controlled to stay within certain limits defined according to the particular application, and hydraulic accumulators may be used in these lines. Although the embodiment represents a system with two variable displacement pumps supplying flow to the pressure rails, it is also possible to develop different configurations for flow supply to the rails. These may include the use of fixed displacement pumps, or other variations known to those skilled in the art. With regard to pressure control in the rails, a feedback signal from one of the positions, velocities, accelerations, and / or forces of multiple actuators can be used to adjust the rail pressure range as well as to vary the flow from the hydraulic flow source, e.g. hydraulic pumps. Thus, in the illustrated configuration, there are nine proportional valves, which may be either pilot or direct type.They are coupled to a multi-chamber actuator 601 that connects each chamber to at least two of all three supply rails 602, 604, and 606. When all chambers are coupled to all three rails, 27 discrete force levels (3. 3 ) is achieved, allowing a large number of fine adjustments given by the proportional valve within each of the 27 discretized levels. This configuration offers superior discretization levels over the prior art by significantly reducing the complexity of the cylinder design, for example from five chambers to three, while providing the availability of a larger number of discrete forces and thus increasing the actuator efficiency. In addition, the higher system efficiency provided by the higher number of available force levels allows for the introduction of small throttle controls in any of the three chambers for precise operational control, while maintaining a high overall system efficiency. In terms of the control approach, this structure has a similar structure to those already described in Figures 6, 7, and 8a and 8b, the only difference being the local pressure controller. The top-level control block diagram is shown in Figure 11, and the details of the pressure controller are shown in Figure 12. In this case, the desired flow rate (Q) at the lowest possible pressure drop is achieved. cmd ) is selected. This block implements a different valve selection logic that selects which valves are active and which are not (u off ) to the nonlinear valve map. The map then outputs valve commands to each one of the proportional valves connected to chamber i. As a result, in this case the controller controls the three proportional valves connected to the same chamber, i.e., the one connected to the HP pressure rail (u pv,i,hp ), those connected to the medium voltage rail (u pv,i,mp ), and those connected to the low-voltage rail (u pv,i,lp ) to output commands.

[0101] Those skilled in the art will recognize that numerous modifications can be made to the specific implementation described above. Implementations should not be limited to the specific limitations described. Other implementations may be possible.

[0102] The symbol "x'" used in this specification (translation) is Represents TIFF2024537315000003.tif32.

Claims

1. M hydraulic rail ports, each configured to be coupled to a pressure rail; N hydraulic chamber ports, each configured to be coupled to a chamber of one or more actuators; N proportional valves, each corresponding to one of the N hydraulic chamber ports, each proportional valve including a rail side coupled to the M hydraulic rail ports and a chamber side coupled to a corresponding hydraulic chamber port, each rail side of the N proportional valves being divided into a supply side configured to supply hydraulic fluid to a corresponding hydraulic chamber port and a return side configured to receive hydraulic fluid from the corresponding hydraulic chamber port; X sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the supply sides of each of the N proportional valves; and Y sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the return sides of each of the N proportional valves; selectively operating each of the on / off valves and the proportional valves to provide selective pressure or flow to each one of the N hydraulic chamber ports; A valve arrangement, wherein M is between 2 and 3, N is between 1 and 4, X has a maximum number M-1, X has a minimum number 1, Y has a maximum number M-1, and Y has a minimum number 1.

2. 2. The valve arrangement of claim 1, wherein the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to selectively define a pressure on the supply side of the proportional valve and further cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

3. 2. The valve arrangement of claim 1, wherein the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to selectively define a pressure on the return side of the proportional valve and further cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

4. - one or more actuators of i) linear or ii) rotary hydraulic type, each actuator having one or more cylinder chambers arranged therein, the total number of cylinder chambers being N; M pressure rails, each of which is a corresponding pressure; A valve device comprising: M hydraulic rail ports, each configured to be coupled to a pressure rail; N hydraulic chamber ports, each configured to be coupled to a chamber of one or more actuators; N proportional valves, each corresponding to one of the N hydraulic chamber ports, each proportional valve including a rail side coupled to the M hydraulic rail ports and a chamber side coupled to a corresponding hydraulic chamber port, each rail side of the N proportional valves being divided into a supply side configured to supply hydraulic fluid to a corresponding hydraulic chamber port and a return side configured to receive hydraulic fluid from the corresponding hydraulic chamber port; X sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the supply sides of each of the N proportional valves; and Y sets of on / off valves and check valves coupling two or more hydraulic rail ports to each of the return sides of each of the N proportional valves; a valve arrangement for selectively operating each of the on / off valves and the proportional valve to provide selective pressure or flow to each one of the N hydraulic chamber ports; and a controller configured to receive one or more desired functional parameters for the one or more cylinder chambers, and in real time: i) receive data from a plurality of sensors associated with the one or more cylinder chambers, and ii) activate and deactivate the N proportional valves and their associated on / off valves to achieve the one or more desired functional parameters, wherein M is between 2 and 3, N is between 1 and 4, X has a maximum number M-1, X has a minimum number 1, Y has a maximum number M-1, and Y has a minimum number 1.

5. 5. The hydraulic circuit of claim 4, wherein the on / off valve and the check valve on the supply side of each of the N proportional valves cooperate to selectively define a pressure on the supply side of the proportional valve and further cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

6. 5. The hydraulic circuit of claim 4, wherein the on / off valve and the check valve on the return side of each of the N proportional valves cooperate to selectively define a pressure on the return side of the proportional valve and further cooperate to prevent fluid flow between a hydraulic rail port having a first pressure and a hydraulic rail port having a second pressure, the first pressure being greater than the second pressure.

7. The hydraulic circuit of claim 4 , wherein each of the M pressure rails is supplied from one or more power sources.

8. The hydraulic circuit of claim 7 , wherein the power source is one of an internal combustion engine or one or more electric motors.

9. 8. The hydraulic circuit of claim 7, wherein pressure in the pressure rail is maintained at a desired level by one or more hydrostatic pumps, either fixed or variable displacement.

10. The hydraulic circuit of claim 9 , wherein real-time measured conditions including pressure, force, torque, position, and velocity are used to regulate desired pressure levels and associated ranges of variation in the pressure rail.

11. The hydraulic circuit of claim 4 , wherein the one or more functional parameters include one of force, velocity, or position.

12. 5. The hydraulic circuit of claim 4, wherein the controller controls the N proportional valves and the associated on / off valves based on minimizing energy losses between the supply side and the return side of each of the N proportional valves.

13. The hydraulic circuit of claim 4 , wherein the controller utilizes the data from the plurality of sensors associated with the one or more cylinder chambers in one or more feedback loops.

14. a hydraulic actuator having three chambers disposed therein; Three hydraulic rails: i) a high pressure rail, ii) a medium pressure rail, and iii) a low pressure rail; and up to nine proportional control hydraulic valves coupled to said hydraulic actuator, each chamber being coupled to one of said three hydraulic rails via a proportional valve, and continuous force control being achieved by proportionally controlling the opening area of ​​each proportional valve.

15. 15. The hydraulic force generator of claim 14, wherein the three hydraulic rails are fed from a power source, each of the three hydraulic rails representing hydraulic power provided by one hydrostatic pump having an outlet that feeds each of the three hydraulic rails via a directional valve, or two or more hydrostatic pumps are used to provide hydraulic power to the three hydraulic rails, the one or more hydrostatic pumps being based on one of a fixed or variable displacement.

16. 16. The hydraulic power generator of claim 15, wherein the single power source is an internal combustion engine, or one or two electric motors powered by a battery pack.

17. 15. The hydraulic pressure generator of claim 14, wherein real-time measured conditions including pressure, force, position, and velocity are used to regulate desired pressure levels and associated ranges of variation in the pressure rail.

18. At least one hydraulic actuator having N chambers disposed therein, N being 1 to 3; and Three hydraulic rails including: i) a high pressure rail, ii) a medium pressure rail, and iii) a low pressure rail; up to N2 sets of proportional control hydraulic valves, one set for each of and coupled to each of said at least one hydraulic actuator, each of said N chambers of each of said at least one actuator being coupled to said three hydraulic rails via a respective one of said N2 sets of proportional control hydraulic valves, and continuous force control is achieved by proportionally controlling the opening area of ​​each of said N2 sets of proportional control hydraulic valves; and a control unit serving to adjust the corresponding opening area of ​​each of the N 2 sets of proportional control hydraulic valves such that closed-loop pressure control is achieved by fluid throttling in each one of the N chambers of the at least one hydraulic actuator.

19. The hydraulic control system of claim 18, wherein each of said at least one hydraulic actuator includes a pressure sensor in the hydraulic line upstream and downstream of each of said N2 sets of said proportional control hydraulic valves.

20. The hydraulic control system of claim 18, further comprising a position or speed sensor in the closed loop pressure control.

21. 20. The hydraulic control system of claim 18, wherein at least one of the three hydraulic rails is supplied from a power source including at least one hydrostatic pump, the at least one hydrostatic pump being based on one of a fixed or variable displacement.

22. 22. The hydraulic control system of claim 21, wherein the power source further comprises one of an internal combustion engine or one or two electric motors powered by a battery pack.

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