Electric control of hydraulic systems of construction machines

Abstract

A hydraulic system controller (310) is disclosed. The hydraulic system controller can determine a maximum active circuit pressure of a set of active hydraulic circuits (220) of a hydraulic system (200), wherein the hydraulic system includes a hydraulic pump (202) to flow fluid through the set of active hydraulic circuits; determine a circuit pressure of a hydraulic circuit of the hydraulic system; determine a desired circuit delta pressure of the hydraulic circuit based on a hydraulic flow command of the hydraulic circuit and the circuit pressure; determine a circuit valve setting of a circuit valve (222) of the hydraulic circuit based on the desired circuit delta pressure and a pressure difference between the maximum active circuit pressure and the circuit pressure; and cause a control device (340) to set a position of the circuit valve (222) according to the circuit valve setting.

Description

Technical Field

[0001] This disclosure generally relates to a hydraulic system, and for example to the electrical control of the hydraulic system. Background Technology

[0002] Construction machinery, such as excavators or other similar types of vehicles, can be used to perform one or more site operations (e.g., material transfer, digging, shoveling, bulldozing, etc.). Typically, such machines include hydraulic systems to perform site operations to control the movement of the machine and / or its components. For example, a hydraulic system can be used to control the machine's implements. More specifically, the hydraulic system of an excavator can be used to control the movement of the excavator, the rotation of the excavator's body (e.g., for swinging operations), and / or the movement of the excavator's implements, including the boom, stick, bucket, etc.

[0003] In many cases, hydraulic systems include multiple hydraulic pumps and / or hydraulic circuits, each including multiple circuit valves. More specifically, in the prior art, hydraulic circuits may include main spool valves that allow or deny flow through each circuit and flow control valves for hydraulically controlling the flow of fluid through the hydraulic system based on sensed pressure and hydraulic flow commands from the hydraulic circuit, which may be based on operator input to the hydraulic system. Therefore, in such cases, hydraulic flow balance between the various hydraulic circuits is achieved through hydraulically controlling one or more of the multiple valves within each hydraulic circuit.

[0004] A method for a control device for construction machinery is disclosed in Chinese Patent No. CN105008623 (“'623 Patent”), issued to Akinori et al. on July 14, 2017. In particular, the '623 Patent describes a control device for a work equipment that controls a control valve, a pilot hydraulic line opening, and includes a pressure sensor.

[0005] Although the '623 patent describes the detection of pilot pressure regulated by a control valve, in the '623 patent, after the first control valve provides pressure regulation of the hydraulic oil supplied by the opposing directional control valve, the spool valve moves to one side in the axial direction; and after the second control valve provides pressure regulation of the hydraulic oil supplied by the opposing directional control valve, the spool valve moves to the other side in the axial direction. Summary of the Invention

[0006] According to some embodiments, a method may include: identifying a set of effective hydraulic circuits of a hydraulic system, wherein the hydraulic system includes a hydraulic pump to cause fluid to flow through the set of effective hydraulic circuits; determining a maximum effective circuit pressure based on the effective circuit pressures of the set of effective hydraulic circuits; comparing the maximum effective circuit pressure with the circuit pressures of the hydraulic circuits of the hydraulic system to determine a pressure difference between the maximum effective circuit pressure and the circuit pressures; determining a desired circuit delta pressure of the hydraulic circuit based on a hydraulic flow command of the hydraulic circuit and the circuit pressures; determining a circuit valve setting of a circuit valve of the hydraulic circuit corresponding to the pressure reduction based on the desired circuit delta pressure and a pressure reduction less than the pressure difference; and causing a control device to set the position of the circuit valve according to the circuit valve setting to reduce the pressure difference.

[0007] According to some embodiments, a hydraulic system controller may include a memory and a processor communicatively coupled to the memory, the processor being configured to: obtain the loop pressure of a hydraulic circuit of a hydraulic system, wherein the hydraulic system includes a hydraulic pump to cause fluid to flow through a set of effective hydraulic circuits; determine the effective loop pressure of the set of effective hydraulic circuits; determine the maximum effective loop pressure of the hydraulic system based on the effective loop pressure; determine the desired loop delta pressure of the hydraulic circuit based on a hydraulic flow command of the hydraulic circuit and the loop pressure; determine the loop valve setting of a loop valve of the hydraulic circuit based on the desired loop delta pressure and the pressure difference between the maximum effective loop pressure and the loop pressure; and instruct a control device based on the loop valve setting to set the position of the loop valve to reduce the opening through the loop valve and reduce the pressure difference.

[0008] According to some embodiments, a hydraulic system may include: a hydraulic pump for supplying fluid from a main line to the hydraulic system; a plurality of hydraulic circuits configured to control a plurality of components of a machine; a plurality of circuit valves for controlling fluid flow accordingly through the plurality of hydraulic circuits; and a controller configured to: determine a maximum effective circuit pressure of a set of effective hydraulic circuits of the hydraulic system, wherein the hydraulic system includes a hydraulic pump to allow fluid to flow through the set of effective hydraulic circuits; determine the circuit pressure of the hydraulic circuits of the hydraulic system; determine a desired circuit delta pressure of the hydraulic circuits based on hydraulic flow commands of the hydraulic circuits and the circuit pressures; determine a circuit valve setting of the circuit valves of the hydraulic circuits based on the desired circuit delta pressure and a pressure difference between the maximum effective circuit pressure and the circuit pressures; and cause a control device to set the position of the circuit valves according to the circuit valve setting. Attached Figure Description

[0009] Figure 1This is a diagram of the exemplary machine described in this article.

[0010] Figure 2 This is a schematic diagram of the exemplary hydraulic system described herein.

[0011] Figure 3 This is a diagram of an exemplary system in which the exemplary apparatus and / or exemplary methods described herein may be implemented.

[0012] Figure 4 This is a diagram illustrating an example of the relationship between flow rate and limiting hydraulic circuits, as described in this article.

[0013] Figure 5 This is a flowchart of an exemplary process associated with the electrical control of the hydraulic system described herein. Detailed Implementation

[0014] This disclosure relates to the electrical (or electronic) control of a hydraulic system using a hydraulic system controller. The hydraulic system controller is universally applicable to any machine using such a hydraulic system. The term "machine" can refer to any machine performing operations associated with an industry such as mining, construction, agriculture, transportation, or any other sector. As some examples, the machine can be a vehicle, backhoe loader, cold planer, wheel loader, compactor, log stacker, forestry machinery, harvester, combine harvester, excavator, industrial loader, boom loader, material handling machine, grader, pipelaying machine, road reclaimer, skid steer loader, timber harvester, telescopic boom forklift, tractor, bulldozer, tractor scraper, or other above-ground, underground, or marine equipment. Furthermore, one or more implements can be connected to the machine and driven by hydraulic components (e.g., cylinders, actuators, solenoids, valves, etc.) of the hydraulic circuit of the hydraulic system and / or controlled by the hydraulic system controller, as described herein.

[0015] Figure 1 This is a diagram of the exemplary machine 100 described herein. Figure 1 As shown, machine 100 is embodied as an earthmoving machine, such as an excavator. Alternatively, machine 100 may be a tractor truck, bulldozer, loader, backhoe, excavator, motor grader, wheeled tractor scraper, or another earthmoving machine.

[0016] like Figure 1As shown, machine 100 includes a ground engagement member 102 for propelling machine 100, such as tracks, wheels, rollers, etc. The ground engagement member 102 is mounted on a vehicle body 104 and driven by one or more engines and / or drivetrains. The vehicle body 104 supports a rotatable machine body 106 and an operator station 108. The operator station 108 is supported by and / or included within the machine body 106, which may be supported by a rotatable frame located between the machine body 106 and the vehicle body 104. The operator station 108 includes one or more operator interfaces 110 (shown as integrated displays and operator controls, such as joysticks).

[0017] like Figure 1 As shown, machine 100 includes implement 112, which includes boom 114, stick 116, and bucket 118. Implement 112 may include other types of working tools, such as hammer drills, rippers, etc. As described herein, movement of machine body 106 and / or movement of implement 112 (e.g., relative to machine body 106) may be controlled and / or performed by a hydraulic system. As described herein, the hydraulic system may include multiple hydraulic circuits to individually and / or independently control one or more functions of machine 100, machine body 106, and / or implement 112. Such functions and / or operations may include entry or exit operations associated with boom 114, extension or retraction operations associated with stick 116, scooping or scooping operations associated with bucket 118, swing functions associated with machine body 106, etc. Such functions may be performed in association with one or more operations of the machine (e.g., digging operations, material transfer operations, travel operations, etc.).

[0018] like Figure 1 As shown, boom 114 is pivotally mounted to machine body 106 at its proximal end. Boom 114 can be hinged relative to machine body 106 via boom cylinder 120 of a hydraulic system (e.g., a fluid-actuated cylinder, such as a hydraulic cylinder, pneumatic cylinder, etc.). Stick 116 is pivotally mounted to boom 114 at its proximal end at its distal end. Stick 116 can be hinged relative to boom 114 via stick cylinder 122 of a hydraulic system. Bucket 118 is pivotally mounted to stick 116 at its proximal end at its distal end. Bucket 118 can be hinged relative to stick 116 via bucket cylinder 124 of a hydraulic system.

[0019] The hydraulic system of machine 100 may include a hydraulic pump 126 that supplies a flow source (e.g., a fixed or variable flow rate) of fluid (e.g., oil or other types of hydraulic fluid) to multiple hydraulic circuits of the hydraulic system (e.g., various hydraulic circuits associated with boom cylinder 120, stick cylinder 122, bucket cylinder 124, one or more swing cylinders for swinging the machine body 106, etc.). According to some embodiments, hydraulic pump 126 may be a single (or unique) hydraulic pump 126 configured to control the multiple functions described herein. Additionally or alternatively, hydraulic pump 126 may be one of multiple hydraulic pumps configured to provide a single flow source of fluid to the machine's hydraulic system in combination. Hydraulic pump 126 supplies fluid from a main line fluidly connected to the discharge end of the hydraulic pump to multiple hydraulic circuits. As described herein, the flow through the multiple hydraulic circuits can be controlled by electromechanical control of the individual circuit valves of the multiple hydraulic circuits. As further described herein, the circuit valve of a separate hydraulic circuit may be a unique (or single) circuit valve for that separate hydraulic circuit.

[0020] like Figure 1 As shown, machine 100 may include controller 128 (e.g., electronic control module (ECM)) and multiple sensors 130 (referred to herein individually as "sensors 130" and collectively as "sensors 130"). Controller 128 may control and / or monitor the operation of machine 100. For example, controller 128 may control and / or monitor the operation of machine 100 based on signals from sensors 130 and / or operator input received from operator interface 110. Controller 128 may include and / or be associated with a hydraulic system controller configured to control a hydraulic system as described herein.

[0021] like Figure 1As shown, sensor 130 is mounted at different locations on and / or within various components or parts of machine 100. For example, sensor 130 may include one or more motion sensors (e.g., cameras, accelerometers, gyroscopes, inertial measurement sensors, velocity sensors, position sensors, etc.) located on the machine body 106, boom 114, stick 116, and bucket 118. In such an example, the controller can detect and / or determine movement of machine 100, movement of the machine body, movement of implement 112, position of machine 100 (e.g., relative to the environment of machine 100), orientation of machine 100, etc., based on information received from sensor 130. Additionally or alternatively, sensor 130 may include one or more pressure sensors included within the actuation cylinder of machine 100 (e.g., at the head end, at the rod end, in fluid lines leading to or from the actuation cylinder, etc.). In such an example, controller 128 can determine one or more pressures associated with boom cylinder 120, stick cylinder 122, bucket cylinder 124, swing cylinder, etc.

[0022] As mentioned above, providing Figure 1 As an example. Other examples may be combined with... Figure 1 The descriptions are different.

[0023] Figure 2 This is a schematic diagram of an exemplary hydraulic system 200 described herein. The hydraulic system 200 includes a hydraulic pump 202, a feed line 204, a main line 206, a fluid reservoir 208, a controller 210, and multiple hydraulic circuits 220a to 220f (collectively referred to herein as "hydraulic circuit 220"). The feed line 204 is fluidly connected to the fluid reservoir 208 and the inlet end of the hydraulic pump 202. The hydraulic pump 202 can be any suitable fluid pumping mechanism configured to draw fluid from the fluid reservoir 208 through the feed line 204, causing the fluid to flow through the main line 206 to the hydraulic circuit 220 and back to the fluid reservoir 208. The main line 206 is fluidly connected to the pump's outlet, the return line (and / or return valve) of the hydraulic circuit 220, and the fluid reservoir 208. The main line 206 can be a single flow source configured to supply a corresponding fluid flow through the hydraulic circuit 220. The controller 210 can correspond to... Figure 1 The controller 128 is configured to control the flow of fluid through the hydraulic circuit, as described herein.

[0024] exist Figure 2In this circuit, hydraulic circuit 220 includes corresponding circuit valves 222a to 222f (collectively referred to as "circuit valves 222"), corresponding pressure sensor configurations 230a to 230f (collectively referred to as "pressure sensor configurations 230"), corresponding valve control devices 240a to 240f (collectively referred to as "valve control devices 240"), and corresponding cylinders 250a to 250f (collectively referred to as "cylinders 250"). Hydraulic circuit 220 can be connected to... Figure 1 The various functions of machine 100 and / or implement 112 are associated. As a specific example, hydraulic circuits 220a and 220b can control the directional movement of machine 100, hydraulic circuit 220c can control the swing (or rotation) of machine body 106, hydraulic circuit 220d can control boom 114 (e.g., cylinder 250d can correspond to boom cylinder 120), hydraulic circuit 220e can control stick 116 (e.g., cylinder 250e can correspond to stick cylinder 122), and hydraulic circuit 220f can control bucket 118 (e.g., cylinder 250f can correspond to bucket cylinder 124).

[0025] The loop valve 222 can be any suitably configured valve that can be controlled by a corresponding valve control device 240 (e.g., based on instructions received from the controller 210). For example, the loop valve 222 can be a separately configured spool valve with electromechanical configurations, which are configured (e.g., according to responsiveness, performance, size, operating range, cylinder type, etc.) specifically for the functional control of cylinder 250.

[0026] During operation, and depending on the configuration of the circuit valve 222 (e.g., based on the setting or position of the circuit valve), the hydraulic pump 202 causes fluid to flow into, through, and / or from the hydraulic circuit 220. In the system including the hydraulic pump 202... Figure 2 In the example, due to the physical characteristics of the hydraulic system 200, any adjustment to the opening of one of the circuit valves 222 may affect the flow through other hydraulic circuits 220 not associated with circuit valve 222. For example, closing circuit valve 222a or reducing the area of ​​that circuit valve may increase the flow rate of fluid through any of the effective hydraulic circuits 220b to 220f. On the other hand, opening circuit valve 222a or increasing the area of ​​that circuit valve may decrease the flow rate of fluid through any of the effective hydraulic circuits 220b to 220f. As described herein, a hydraulic circuit 220 is an "effective circuit" when the corresponding circuit valve 222 has an open passage that allows fluid to flow through it.

[0027] Pressure sensor configuration 230 may include one or more pressure sensors configured to monitor various pressures in hydraulic circuit 220. For example, pressure sensor configuration 230a may include a first pressure sensor to measure and / or indicate the pressure at the rod end of cylinder 250a, the pressure at the head end of cylinder 250a, and / or the pressure in the circuit line between circuit valve 222a and cylinder 250a. As shown, the pressure sensor configuration is communicatively coupled to controller 210. Therefore, controller 210 can receive, acquire, and / or monitor pressure measurements associated with hydraulic system 200.

[0028] As described herein, controller 210 causes valve control device 240 to configure or position one or more components of circuit valve 222 (e.g., spool, stem, actuator, plug, orifice, etc.) to increase and / or decrease the opening of circuit valve 222 (e.g., by increasing or decreasing the area of ​​the passageway through one or more respective circuit valves 222). More specifically, controller 210 may instruct valve control device 240 to set the position of the spool of circuit valve 222 to control the size of the opening and (e.g., according to hydraulic flow commands from a hydraulic system, one or more hydraulic circuits 220, etc.) accordingly control the flow of fluid through hydraulic circuit 220.

[0029] As mentioned above, providing Figure 2 As an example. Other examples may be combined with... Figure 2 The descriptions are different.

[0030] Figure 3 This is a diagram of an exemplary system 300, in which the exemplary apparatus and / or exemplary methods described herein can be implemented. Figure 3 As shown, system 300 may include a hydraulic system controller 310, which includes a processor 312, a memory 314, a valve control module 316, and a valve mapping module 318. Furthermore, system 300 may include an operator interface 320, sensors 330, and / or a valve control device 340 (referred to herein solely as "control device 340"). The devices of system 300 can be interconnected via wired, wireless, or a combination of wired and wireless connections. As described herein, hydraulic system controller 310 is configured to control the hydraulic system (e.g., using valve control device 340) based on hydraulic flow commands determined from operator input from operator interface 320, sensor measurements from sensor 330, etc. Figure 2 Hydraulic system 200).

[0031] Operator interface 320 (e.g., corresponding to Figure 1The operator interface 110 may include one or more devices associated with receiving, generating, storing, processing, and / or providing information associated with controlling machine 100 and / or implement 112. Such input components may include electronic user interfaces (e.g., touchscreens, keyboards, keypads, etc.), mechanical user interfaces (e.g., accelerator pedals, deceleration pedals, brake pedals, gear shifters, etc.), and / or hydraulic user interfaces (e.g., hydraulic levels, hydraulic pedals, etc.). As described herein, the hydraulic system controller 310 may determine hydraulic flow commands based on operator input received from the operator interface 320.

[0032] Sensor 330 may include any type of sensor configured to monitor the operating status of machine 100 and / or implement 112. Sensor 330 may correspond to... Figure 1 Sensor 130 and / or Figure 2 Pressure sensor configuration 230. Sensor 330 may include one or more sensors for determining the operating status of machine 100 and / or implements, such as pressure sensors (e.g., for determining pressure in hydraulic system lines and / or cylinders, pressure in the engine of machine 100, etc.), temperature sensors (e.g., for detecting the temperature of air, exhaust, components, coolant, etc.), position sensors (e.g., for detecting the position of valves, actuators, engine components (e.g., pistons), speed sensors (e.g., for detecting machine speed, engine speed, etc.), etc.

[0033] Valve control device 340 includes components that can be electrically controlled by hydraulic system controller 310 through one or more hydraulic circuits (e.g., Figure 2 Any suitable device for the flow of fluid in the hydraulic circuit 220. For example, control device 340 may include a circuit valve capable of opening and / or closing (e.g., Figure 2 The valve control device 340 may include one or more actuators, solenoids, switches, etc., of the circuit valve 222. In some embodiments, the valve control device 340 may provide feedback to the hydraulic system controller 310. For example, the valve control device 340 may provide and / or indicate the position of the spool (or other component) of the circuit valve (whether the circuit valve is open or closed), the area of ​​the circuit valve opening, etc. Additionally or alternatively, one or more of the sensors 330 may be associated with and / or included within the valve control device 340. In this case, the sensors 330 may provide information associated with and / or that may represent the status or setting of the circuit valve associated with the valve control device 340.

[0034] The hydraulic system controller 310 can correspond to Figure 1 Controller 128 and / or Figure 2The controller 210. The processor 312 is implemented in hardware, firmware, and / or a combination of hardware and software. The processor 312 may include a central processing unit (CPU), a graphics processing unit (GPU), an accelerated processing unit (APU), a microprocessor, a microcontroller, a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or another type of processing unit. The processor 312 may include one or more processors that can be programmed to perform functions. The memory 314 includes random access memory (RAM), read-only memory (ROM), and / or another type of dynamic or static storage device (e.g., flash memory, magnetic memory, and / or optical memory) that stores information and / or instructions (e.g., information and / or instructions associated with valve control module 316 and valve mapping module 318) for use by the processor 312.

[0035] Valve control module 316 is configured to determine and / or control valve control device 340 to control the flow rate of fluid through one or more hydraulic circuits of machine 100. Valve control module 316 may receive measurements from sensor 330 associated with the operating status of machine 100 and / or implement 112. Additionally or alternatively, valve control module 316 may receive operator input from operator interface 320, which is associated with the operator performing operations and / or controlling functions of machine 100 and / or implement 112 associated with machine 100 and / or implement, as described herein.

[0036] Valve control module 316 can be configured to monitor the pressure of the hydraulic system using multiple pressure sensors of sensor 330. Based on the pressure of the entire hydraulic system, valve control module 316 can instruct valve control device 340 to adjust the settings of one or more loop valves to increase or decrease the flow rate through a specific hydraulic loop. For example, valve control module 316 can identify which hydraulic loops of the hydraulic system are active (e.g., which hydraulic loops have a non-zero flow rate) based on pressure and / or operator input. For those active hydraulic loops, valve control module 316 can determine the maximum active loop pressure (e.g., the highest loop pressure relative to the active hydraulic loops). Valve control module 316 can compare the maximum active loop pressure with the desired loop delta pressure of the hydraulic loop (e.g., one of the active hydraulic loops) and determine whether the area of ​​the loop valve of that hydraulic loop can be reduced to increase the flow rate of fluid in the hydraulic loop with the maximum active loop pressure.

[0037] Valve control module 316 can determine the desired loop delta pressure for a particular hydraulic circuit based on the desired hydraulic flow command (e.g., determined from operator input via operator interface 320, automatic flow command generated based on sensor measurements from sensor 330, etc.) and the actual or operating pressure indicated by one of the sensors 330 monitoring the hydraulic circuit. If the desired loop delta pressure indication can reduce the area (e.g., the measured pressure is higher than the pressure corresponding to the hydraulic flow command), valve control module 316 uses valve mapping module 318 to instruct valve control device 340 of the hydraulic circuit to correspondingly reduce the area of ​​the loop valve of the hydraulic circuit. In this way, the flow rate (and / or pressure) of the hydraulic circuit associated with the maximum effective loop pressure can be increased by controlling another loop valve.

[0038] Valve control module 316 may store information and / or logic in valve mapping module 318. For example, such information may include a list of multiple valve mappings (shown as “M1”, “M2”, “M3”) corresponding to certain circuit valves in the hydraulic system, along with circuit-associated priorities (e.g., indications of whether control of one or more hydraulic circuits takes precedence over control of another under default and / or specific conditions), and the valve mappings themselves. Valve mappings may map valve positions to specific areas of circuit valves, specific pressures of hydraulic circuits, specific flow rates of hydraulic circuits, etc. Therefore, valve mappings stored and / or maintained by valve mapping module 318 may be valve-specific, operating mode-specific, and / or function-specific valve mappings. In this way, valve control module 316 may cause valve control device 340 to saturate delta pressure compensation (e.g., opening adjustment) according to specific adjustment strategies for each hydraulic circuit.

[0039] Valve mappings can be stored in a data structure (e.g., a database, table, index, chart, etc.) of memory 314 and / or in a memory communicatively coupled to memory 314. Valve mappings can be associated with loop valve settings such as desired pressure, desired flow rate, desired loop delta pressure, etc. Furthermore, a valve mapping for a specific loop valve can correspond to a mapping of a specific position of the loop valve's spool to the area of ​​the valve opening for a specific operating condition of machine 100 and / or tool 112. In this way, valve mappings identify loop valve settings and / or the location of loop valve components. Valve control module 316 can use the valve mappings of valve mapping module 318 to limit the flow rate through one or more hydraulic loops of the hydraulic system of machine 100.

[0040] Figure 3 The number and arrangement of the devices shown are provided as an example. In practice, with Figure 3 Compared to those shown, there may be additional devices, fewer devices, different devices, or devices with different arrangements. Furthermore, Figure 3The two or more devices shown can be implemented within a single device, or Figure 3 The single device shown can be implemented as multiple distributed devices. Additionally or alternatively, a group of devices in system 300 (e.g., one or more devices) can perform one or more functions performed by another group of devices in system 300.

[0041] Figure 4 This is a diagram of Example 400, as described herein, relating to the flow rate of a limited hydraulic circuit. Example 400 may correspond to... Figure 3 The hydraulic system controller 310 performs flow rate limiting schemes and / or analyses.

[0042] like Figure 4 As shown, the hydraulic system controller 310 can determine whether a hydraulic flow command for a hydraulic circuit is associated with a preferred hydraulic circuit based on one or more defined operating conditions associated with machine 100 and / or implement 112. If the hydraulic flow command is associated with a preferred hydraulic circuit (which can be determined based on valve mapping of valve mapping module 318), the hydraulic system controller 310 controls the hydraulic system according to the hydraulic flow command. For example, the hydraulic system controller 310 can cause the valve control device 340 of the hydraulic system to control the flow rate of the effective hydraulic circuit to meet the desired hydraulic flow command.

[0043] If the hydraulic system controller 310 determines, based on operating conditions, that a hydraulic flow command is not associated with a preferred hydraulic circuit, then the hydraulic system controller 310 controls the hydraulic system according to an operating condition-based limiting scheme. For example, the hydraulic system controller 310 may control the valve control device 340 to limit the flow rate associated with one or more hydraulic circuits based on a flow rate limiting strategy for the hydraulic circuit and / or based on adjustments to the operating condition-based hydraulic flow command.

[0044] As an example, the extension function associated with the boom 116 (e.g., for digging operations) can be limited based on operating conditions indicating the swing speed of the machine body 106 and / or the circuit pressure associated with the hydraulic circuit controlling the swing of the machine body 106. In this case, the hydraulic system controller 310 can cause the valve control device 340 to limit the flow rate of the hydraulic circuit of the boom 116 to less than a certain maximum flow rate. Additionally or alternatively, the extension function can be limited based on the ongoing boom flow command associated with the boom cylinder 120, the bucket flow command associated with the bucket cylinder 124, and / or the swing flow command associated with the swing cylinder. As another example, based on operating conditions indicating that the machine 100 is moving (e.g., during travel operations), the hydraulic flow command associated with the bucket cylinder 124 can be ignored and / or adjusted to prevent a reduction in the flow rate of the fluid used to move the machine 100. Similarly, hydraulic flow commands for the boom cylinder 120 and / or stick cylinder can be ignored and / or adjusted during mobile operations and / or other types of operating conditions associated with machine 100.

[0045] As mentioned above, providing Figure 4 As an example. Other examples may be combined with... Figure 4 The descriptions are different.

[0046] Figure 5 This is a flowchart of an exemplary process 500 associated with the electrical control of a hydraulic system. In some embodiments, Figure 5 One or more process frames can be executed by a controller (e.g., controller 128, controller 210, hydraulic system controller 310, etc.). In some embodiments, Figure 5 One or more process frames may be executed by another device or a group of devices that are separate from or include the controller, such as valve control devices (e.g., valve control device 240, valve control device 340, etc.).

[0047] like Figure 5 As shown, process 500 may include determining the maximum effective loop pressure of a set of effective hydraulic loops in the hydraulic system (block 510). For example, a controller (e.g., using processor 312, memory 314, valve control module 316, valve mapping module 318, etc.) may determine the maximum effective loop pressure of a set of effective hydraulic loops in the hydraulic system, as described above. The hydraulic system may include a hydraulic pump and / or a single flow source that will cause fluid to flow through the set of effective hydraulic loops.

[0048] The controller can identify the set of effective hydraulic circuits based on one or more hydraulic flow commands associated with one or more hydraulic components controlling the hydraulic system. The controller can determine individual pressure measurements of the set of effective hydraulic circuits based on pressure sensors associated with them, and identify the maximum effective circuit pressure from these measurements.

[0049] like Figure 5 As further shown, process 500 may include determining the loop pressure of the hydraulic circuit of the hydraulic system (block 520). For example, a controller (e.g., using processor 312, memory 314, valve control module 316, valve mapping module 318, etc.) may determine the loop pressure of the hydraulic circuit of the hydraulic system as described above.

[0050] The hydraulic circuit can be one of the set of effective hydraulic circuits. Additionally or alternatively, the hydraulic circuit is a first hydraulic circuit of the hydraulic system with a first circuit valve, and the maximum effective circuit pressure is associated with a second hydraulic circuit of the hydraulic system, different from the first hydraulic circuit. The first and second circuit valves of the second hydraulic circuit can be fluidly connected to the main line of the hydraulic pump.

[0051] like Figure 5 As further shown, process 500 may include determining the desired loop delta pressure of the hydraulic circuit based on the hydraulic flow command and circuit pressure of the hydraulic circuit (block 530). For example, a controller (e.g., using processor 312, memory 314, valve control module 316, valve mapping module 318, etc.) may determine the desired loop delta pressure of the hydraulic circuit, as described above. The controller may determine the hydraulic flow command based on operator input associated with the hydraulic circuit, the operating status of the hydraulic circuit, the operating status of the hydraulic system, the operating status of the machine, etc.

[0052] The loop pressure can correspond to the operating pressure received from the pressure sensor of the hydraulic loop, and the desired loop delta pressure can include the difference between the operating pressure and the desired pressure based on the hydraulic flow command.

[0053] like Figure 5 As further shown, process 500 may include determining the loop valve setting of the hydraulic circuit's loop valve based on the desired loop delta pressure and the pressure difference between the maximum effective loop pressure and the loop pressure (block 540). For example, a controller (e.g., using processor 312, memory 314, valve control module 316, valve mapping module 318, etc.) may determine the loop valve setting of the hydraulic circuit's loop valve based on the desired loop delta pressure and the pressure difference between the maximum effective loop pressure and the loop pressure, as described above.

[0054] The controller can determine when the maximum effective loop pressure is greater than the loop pressure, determine when the desired pressure reduction in the hydraulic circuit is less than the pressure difference between the maximum effective loop pressure and the loop pressure, and determine the location of the loop valve that provides the desired pressure reduction.

[0055] In some implementations, the controller can identify valve mappings associated with the hydraulic circuit that map multiple circuit pressures to corresponding positions of circuit valves, and obtain circuit valve settings from the valve mappings and based on the desired circuit delta pressure that can indicate the position of the circuit valves.

[0056] Additionally or alternatively, the controller may determine an operating condition associated with one of the set of effective hydraulic circuits, determine a flow rate limit associated with the hydraulic circuit based on the operating condition, and determine circuit valve settings based on the flow rate limit. One of the set of effective hydraulic circuits may be associated with the movement of the controlled machine, and the hydraulic circuit may be associated with a component of the controlled machine.

[0057] like Figure 5 As further shown, process 500 may include enabling a control device to set the position of the loop valve according to the loop valve settings (block 550). For example, a controller (e.g., using processor 312, memory 314, valve control module 316, valve mapping module 318, etc.) may enable the control device to set the position of the loop valve according to the loop valve settings, as described above. The controller may provide the loop valve settings to the control device.

[0058] although Figure 5 An exemplary block diagram of process 500 is shown, but in some embodiments, process 500 may include more than Figure 5 The boxes depicted may include more boxes, fewer boxes, different boxes, or boxes with different arrangements. Additionally or alternatively, two or more boxes in process 500 may be executed in parallel.

[0059] Industrial applicability

[0060] The disclosed hydraulic system controller can be used with any machine that uses a hydraulic system to control the machine and / or its implements. The disclosed hydraulic system controller can electrically control the flow of fluid through multiple hydraulic circuits based on monitoring and / or determining the pressure associated with the hydraulic circuits. For example, based on the maximum effective circuit pressure identified in one hydraulic circuit (e.g., the highest circuit pressure relative to a set of effective hydraulic circuits), the hydraulic system controller can determine whether a circuit valve in another hydraulic circuit in the hydraulic system will be adjusted to increase the flow rate of fluid through the hydraulic circuit associated with the maximum effective circuit pressure (e.g., to improve the performance and / or responsiveness of functions or components associated with the hydraulic circuit). In this way, based on communicatively coupled with one or more pressure sensors and / or valve control devices, the hydraulic system controller can automatically control the flow rate and / or fluid distribution throughout the hydraulic system.

[0061] Furthermore, the hydraulic system controller configured as described herein enables the hydraulic system to include a hydraulic pump because multiple (or all) hydraulic circuits can be monitored and controlled simultaneously electromechanically rather than hydraulically. Moreover, since the hydraulic system controller controls the circuit valves of the hydraulic system electromechanically (rather than hydraulically), it allows a hydraulic system comprising multiple hydraulic circuits to independently control the flow rate of fluid through each circuit using individual circuit valves (e.g., one control valve per hydraulic circuit), while simultaneously controlling the flow throughout the entire effective hydraulic circuit. In this way, instead of requiring multiple separate hydraulic pumps for the hydraulic system and / or multiple separate circuit valves for a single hydraulic circuit, the hydraulic system can be controlled using a hydraulic pump, a single flow source, and / or a single circuit valve for the hydraulic circuit used by the hydraulic system controller. This reduces hardware resources, lowers the complexity of the hydraulic system, and (e.g., by reducing the weight of the hydraulic system, its power requirements and / or consumption) improves the efficiency of the hydraulic system and / or the machines associated with it.

Claims

1. A method for controlling a hydraulic system (200), comprising: Identify a set of valid hydraulic circuits (220) of the hydraulic system (200). The hydraulic system (200) includes a hydraulic pump (202) to cause fluid to flow through the set of effective hydraulic circuits (220); The maximum effective circuit pressure is determined based on the effective circuit pressure of the set of effective hydraulic circuits (220); The maximum effective circuit pressure is compared with the circuit pressure of the hydraulic circuit (220) of the hydraulic system (200) to determine the pressure difference between the maximum effective circuit pressure and the circuit pressure; The desired circuit delta pressure of the hydraulic circuit (220) is determined based on the hydraulic flow command and the circuit pressure of the hydraulic circuit (220); Based on the correlation between the desired loop delta pressure and a pressure drop less than the pressure difference, the circuit valve (222) setting of the circuit valve (222) of the hydraulic circuit (220) corresponding to the pressure drop is determined; and The control device (340) sets the position of the circuit valve (222) according to the settings of the circuit valve (222) to reduce the pressure difference.

2. The method of claim 1, wherein the set of valid hydraulic circuits (220) is identified based on one or more hydraulic flow commands associated with one or more hydraulic components controlling the hydraulic system (200).

3. The method according to any one of claims 1-2, wherein determining the setting of the loop valve (222) comprises: Identify the valve mapping associated with the hydraulic circuit (220). The valve mapping wherein the valve mapping maps multiple loop pressures to corresponding positions of the loop valve (222); and The circuit valve (222) setting is obtained from the valve mapping and based on the desired circuit delta pressure. The loop valve (222) is configured to identify the location.

4. The method according to any one of claims 1-3, wherein determining the setting of the loop valve (222) comprises: Determine the operating condition associated with one of the set of effective hydraulic circuits (220); The flow rate limit associated with the hydraulic circuit (220) is determined based on the operating conditions; as well as The setting of the loop valve (222) is determined based on the flow rate limitation.

5. The method according to any one of claims 1-4, wherein setting the position by the control device (340) comprises: The circuit valve (222) is provided to the control device (340). The loop valve (222) is configured to identify the location.

6. The method according to any one of claims 1-5, wherein the hydraulic circuit (220) is one of the set of effective hydraulic circuits (220).

7. The method according to any one of claims 1-6, wherein the hydraulic circuit (220) is a first hydraulic circuit (220) of the hydraulic system (200), and the maximum effective circuit pressure is associated with a second hydraulic circuit (220) of the hydraulic system (200) that is different from the first hydraulic circuit (220).

8. A hydraulic system (200) for a machine (100), said hydraulic system (200) comprising: A hydraulic pump (202) for supplying fluid from the main pipeline to the hydraulic system (200); Multiple hydraulic circuits (220) configured to control multiple components of the machine (100); Multiple circuit valves (222) for controlling the corresponding flow of fluid through the multiple hydraulic circuits (220); as well as Controller (310), the controller is configured to: Determine the maximum effective circuit pressure of a set of effective hydraulic circuits (220) of the hydraulic system (200). The hydraulic system (200) includes a hydraulic pump (202) to cause fluid to flow through the set of effective hydraulic circuits (220); Determine the circuit pressure of the hydraulic circuit (220) of the hydraulic system (200); The desired circuit delta pressure of the hydraulic circuit (220) is determined based on the hydraulic flow command and the circuit pressure of the hydraulic circuit (220); Based on the desired loop delta pressure and the pressure difference between the maximum effective loop pressure and the loop pressure, the loop valve (222) setting of the hydraulic circuit (220) is determined; and The control device (340) sets the position of the loop valve (222) according to the settings of the loop valve (222).

9. The hydraulic system (200) of claim 8, wherein the controller (310) is configured to determine the hydraulic flow command based on at least one of the following: Operator inputs associated with the hydraulic circuit (220), The operating status of the hydraulic circuit (220), The operating status of the hydraulic system (200), or The operating status of the machine (100).

10. The hydraulic system (200) according to claim 8, wherein the controller (310) is configured to: determine the setting of the circuit valve (222) when: The maximum effective loop pressure is determined to be greater than the loop pressure; The desired pressure reduction in the hydraulic circuit (220) is determined to be less than the pressure difference between the maximum effective circuit pressure and the circuit pressure; and Determine the location of the loop valve (222) that provides the desired pressure reduction.

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