Hydraulic Two-in-One Control System and Method for Construction Machinery

Abstract

The present invention discloses a hydraulic two-in-one control system and method for construction machinery. The system includes: an instrument controller, an instrument system selection switch, a hydraulic two-in-one controller, a hydraulic system selection switch, and an engine system selection switch. The instrument controller includes a first input module, a first control strategy module, and a first output module that are electrically connected; the instrument system selection switch is electrically connected to the first input module of the instrument controller; the hydraulic two-in-one controller is electrically connected to the instrument controller through a CAN bus, and the hydraulic two-in-one controller includes a second input module, a second control strategy module, and a second output module that are electrically connected; the hydraulic system selection switch is electrically connected to the second input module of the hydraulic two-in-one controller. The hydraulic two-in-one control system for construction machinery of the present invention improves the integration degree of control functions, the signal fast response performance, and also improves the utilization rate of hardware resources and reduces fuel consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of engine control, and particularly to a hydraulic two-in-one control system and method for construction machinery. Background Art

[0002] The control system of construction machinery, especially excavators, mainly consists of an engine control system, a hydraulic control system, and an instrument control system. Existing technologies are independently controlled by their respective controllers, and the controllers communicate with each other using the CAN bus. Due to various technical characteristics of the CAN bus, such as low communication baud rate and increased load rate when too many signals are transmitted, which affects signal quality, etc., the existing control system technical solutions for construction machinery have a slow response to the driver's throttle demand and the engine's rotational speed demand for the hydraulic controller, thus failing to achieve ideal driving control and fuel-saving effects.

[0003] When the driver inputs an instruction to increase the throttle to the instrument controller through the throttle selection switch, the instrument controller needs to transmit this instruction to the hydraulic controller through the CAN bus. When the hydraulic controller converts this instruction into an engine speed signal, it needs to transmit this speed signal to the engine controller through the CAN bus. When the excavator is in normal working conditions, such as loose and evenly distributed soil, the disadvantage of the slow response of the engine to the rotational speed demand of the hydraulic controller will not be prominent. However, when the excavator encounters hard soil blocks or stones, the hydraulic controller will send a demand for a higher rotational speed to the engine controller. Due to the limitation of the CAN bus transmission rate, the engine cannot quickly increase to the required rotational speed to respond to the demand of the hydraulic controller, and there are also situations where the rotational speed control is unstable and fluctuates within a large rotational speed range, thus affecting the fuel consumption of the whole vehicle.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of the present invention and should not be regarded as an admission or any form of implication that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a hydraulic two-in-one control system and method for construction machinery, which has a simple and reasonable structure, improves the integration degree of control functions, signal fast response, and utilization rate of hardware resources, and reduces fuel consumption.

[0006] To achieve the above object, in a first aspect, the present invention provides a hydraulic two-in-one control system for construction machinery, including: an instrument controller, an instrument system selection switch, a hydraulic two-in-one controller, a hydraulic system selection switch, and an engine system selection switch. The instrument controller includes a first input module, a first control strategy module, and a first output module that are electrically connected; the instrument system selection switch is electrically connected to the first input module of the instrument controller; the hydraulic two-in-one controller is electrically connected to the instrument controller through a CAN bus, and the hydraulic two-in-one controller includes a second input module, a second control strategy module, and a second output module that are electrically connected; the hydraulic system selection switch is electrically connected to the second input module of the hydraulic two-in-one controller; and the engine system selection switch is electrically connected to the second input module of the hydraulic two-in-one controller.

[0007] In an embodiment of the present invention, the hydraulic two-in-one control system for construction machinery further includes a display, which is electrically connected to the first output module of the instrument controller.

[0008] In an embodiment of the present invention, the hydraulic two-in-one control system for construction machinery further includes a hydraulic system sensor, which is electrically connected to the second input module of the hydraulic two-in-one controller.

[0009] In an embodiment of the present invention, the hydraulic two-in-one control system for construction machinery further includes an engine system sensor, which is electrically connected to the second input module of the hydraulic two-in-one controller.

[0010] In an embodiment of the present invention, the hydraulic two-in-one control system for construction machinery further includes a hydraulic system actuator, which is electrically connected to the second output module of the hydraulic two-in-one controller.

[0011] In an embodiment of the present invention, the hydraulic two-in-one control system for construction machinery further includes an engine system actuator, which is electrically connected to the second output module of the hydraulic two-in-one controller.

[0012] In an embodiment of the present invention, the first control strategy module includes an instrument control function unit.

[0013] In an embodiment of the present invention, the second control strategy module includes a hydraulic control function unit and an engine control function unit that are electrically connected.

[0014] In a second aspect, the present invention provides a control method for a hydraulic two-in-one control system for construction machinery. Based on the above-mentioned hydraulic two-in-one control system for construction machinery, the control method for the hydraulic two-in-one control system for construction machinery includes:

[0015] The instrument controller obtains the working mode signal and sends the working mode signal to the hydraulic two-in-one controller via the CAN bus;

[0016] The hydraulic two-in-one controller determines the rotational speed target value according to the current state of the whole vehicle;

[0017] The hydraulic two-in-one controller collects the data sensed by the engine system to obtain the actual engine speed;

[0018] The instrument controller obtains the throttle knob gear signal and sends the throttle knob gear signal to the hydraulic two-in-one controller via the CAN bus;

[0019] Obtain the engine speed deviation value, and use the speed deviation value and the rotational speed target value as input variables to input into the MAPs of the heavy-duty mode, economy mode, and fine mode, so as to obtain the drive current value for the open-loop control of the hydraulic pump;

[0020] Use the rotational speed target value and the throttle knob gear as input variables to input into the PID to obtain the compensation value for the closed-loop control of the hydraulic pump;

[0021] Obtain the drive current for the closed-loop control of the hydraulic pump, so as to drive the hydraulic pump in the hydraulic system actuator to work.

[0022] In an embodiment of the present invention, the engine speed deviation value is obtained by subtracting the actual engine speed from the rotational speed target value.

[0023] Compared with the prior art, according to the hydraulic two-in-one control system and method for construction machinery of the present invention, the structure is simple and reasonable, the integration degree of the control function, the signal fast response performance are improved, and the utilization rate of hardware resources is improved, and the fuel consumption is reduced. Description of the Drawings

[0024] Figure 1 is a schematic structural diagram of a hydraulic two-in-one control system for construction machinery in Embodiment 1 of the present invention;

[0025] Figure 2 is a schematic flow diagram of a hydraulic two-in-one control method for construction machinery in Embodiment 2 of the present invention;

[0026] Figure 3 is a schematic wireframe diagram of the hydraulic pump control function based on the engine speed in the hydraulic two-in-one control method for construction machinery in Embodiment 2 of the present invention.

[0027] Main reference numeral description:

[0028] 1 - Instrument controller, 2 - First input module, 3 - First control strategy module, 4 - First output module, 5 - Instrument system selection switch, 6 - Hydraulic two-in-one controller, 7 - Second input module, 8 - Second control strategy module, 9 - Second output module, 10 - Hydraulic system selection switch, 11 - Engine system selection switch, 12 - Display, 13 - Hydraulic system sensor, 14 - Engine system sensor, 15 - Hydraulic system actuator, 16 - Engine system actuator, 17 - Instrument control function unit, 18 - Hydraulic control function unit, 19 - Engine control function unit, 20 - Working mode, 21 - RPM target value, 22 - Actual engine RPM, 23 - Throttle knob position, 24 - Heavy load mode, 25 - Economy mode, 26 - Fine mode, 27 - PID, 28 - Mode selection switch, 29 - Hydraulic pump closed-loop control drive current. Detailed implementation manners

[0029] The following combines the accompanying drawings to describe in detail the specific implementation manners of the present invention. However, it should be understood that the protection scope of the present invention is not limited by the specific implementation manners.

[0030] Unless otherwise clearly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "having" etc. will be understood to include the stated elements or components, without excluding other elements or other components.

[0031] For ease of understanding, first, the main implementation concepts of each embodiment of the present invention are briefly described.

[0032] In the prior art, after the instrument controller 1 collects the electrical signal of the instrument system selection switch 5, it is converted into a control signal that can be recognized by the CAN bus or displayed by the display 12. After the hydraulic controller collects the electrical signals of the hydraulic system selection switch 10, sensors, etc., it is converted into a control signal that can be recognized by the CAN bus or can drive the hydraulic system actuator 15. After the engine controller collects the electrical signals of the engine system selection switch 11, sensors, etc., it is converted into a control signal that can be recognized by the CAN bus or can drive the engine system actuator 16. When the hydraulic controller needs the relevant control signal in the instrument controller 1 to participate in the calculation of the hydraulic control strategy, it sends a request to the instrument controller 1. When the instrument controller 1 responds to this request, it will transmit this control signal to the hydraulic controller through the CAN bus. Similarly, the control signal of the hydraulic controller can also be transmitted to the instrument controller 1 through the CAN bus. When the hydraulic controller needs the relevant control signal in the engine controller to participate in the calculation of the hydraulic control strategy, it sends a request to the engine controller. When the engine controller responds to this request, it will transmit this control signal to the hydraulic controller through the CAN bus. Similarly, the control signal of the hydraulic controller can also be transmitted to the engine controller through the CAN bus.

[0033] Since each controller is independent in hardware, the signal interaction between them is realized through the CAN bus. Due to limitations such as baud rate and load rate of the CAN bus, the transmission rate and transmission quality are not high, which limits the timeliness and real-time performance of signal transmission, and thus affects the engine control effect and the vehicle fuel-saving effect.

[0034] Embodiment 1

[0035] Figure 1 is a schematic structural diagram of a hydraulic two-in-one control system for construction machinery in Embodiment 1 of the present invention. As Figure 1 shown, Embodiment 1 provides a hydraulic two-in-one control system for construction machinery, including: an instrument controller 1, an instrument system selection switch 5, a hydraulic two-in-one controller 6, a hydraulic system selection switch 10, and an engine system selection switch 11. The instrument controller 1 includes a first input module 2, a first control strategy module 3, and a first output module 4 that are electrically connected; the instrument system selection switch 5 is electrically connected to the first input module 2 of the instrument controller 1; the hydraulic two-in-one controller 6 is electrically connected to the instrument controller 1 through the CAN bus, and the hydraulic two-in-one controller 6 includes a second input module 7, a second control strategy module 8, and a second output module 9 that are electrically connected; the hydraulic system selection switch 10 is electrically connected to the second input module 7 of the hydraulic two-in-one controller 6; and the engine system selection switch 11 is electrically connected to the second input module 7 of the hydraulic two-in-one controller 6.

[0036] In this embodiment, the hydraulic two-in-one control system for construction machinery further includes a display 12, which is electrically connected to the first output module 4 of the instrument controller 1.

[0037] In this embodiment, the hydraulic two-in-one control system for construction machinery further includes a hydraulic system sensor 13, which is electrically connected to the second input module 7 of the hydraulic two-in-one controller 6.

[0038] In this embodiment, the hydraulic two-in-one control system for construction machinery further includes an engine system sensor 14, which is electrically connected to the second input module 7 of the hydraulic two-in-one controller 6.

[0039] In this embodiment, the hydraulic two-in-one control system for construction machinery further includes a hydraulic system actuator 15, which is electrically connected to the second output module 9 of the hydraulic two-in-one controller 6.

[0040] In this embodiment, the hydraulic two-in-one control system for construction machinery further includes an engine system actuator 16, which is electrically connected to the second output module 9 of the hydraulic two-in-one controller 6.

[0041] In this embodiment, the first control strategy module 3 includes an instrument control function unit 17.

[0042] In this embodiment, the second control strategy module 8 includes a hydraulic control function unit 18 and an engine control function unit 19 which are electrically connected.

[0043] Embodiment 2

[0044] Figure 2 is a schematic flowchart of a hydraulic two-in-one control method for construction machinery in Embodiment 2 of the present invention; Figure 3 is a schematic block diagram of the hydraulic pump control function based on the engine speed in a hydraulic two-in-one control method for construction machinery in Embodiment 2 of the present invention. As Figures 2 to 3 shown, Embodiment 2 provides a control method for a hydraulic two-in-one control system for construction machinery. Based on the above-mentioned hydraulic two-in-one control system for construction machinery, the control method of the hydraulic two-in-one control system for construction machinery includes:

[0045] Step S100, the instrument controller 1 acquires the working mode 20 signal and sends the working mode 20 signal to the hydraulic two-in-one controller 6 through the CAN bus;

[0046] Step S200, the hydraulic two-in-one controller 6 determines the rotational speed target value 21 according to the current state of the whole vehicle;

[0047] Step S300, the hydraulic two-in-one controller 6 collects the data sensed by the engine system to obtain the actual engine speed 22;

[0048] Step S400, the instrument controller 1 obtains the signal of the throttle knob gear 23, and sends the signal of the throttle knob gear 23 to the hydraulic two-in-one controller 6 through the CAN bus;

[0049] Step S500, obtain the engine speed deviation value, and use the engine speed deviation value and the speed target value 21 as input variables to input into the MAPs of the heavy-duty mode 24, economy mode 25 and fine mode 26, so as to obtain the drive current value of the open-loop control of the hydraulic pump;

[0050] Step S600, input the speed target value 21 and the throttle knob gear 23 as input variables into the PID 27 to obtain the compensation value of the closed-loop control of the hydraulic pump;

[0051] Step S700, obtain the drive current 29 of the closed-loop control of the hydraulic pump, so as to drive the hydraulic pump in the hydraulic system actuator 15 to work.

[0052] In this embodiment, the engine speed deviation value is obtained by subtracting the actual engine speed 22 from the speed target value 21.

[0053] In practical applications, the connection relationship between the various components of the hydraulic two-in-one control system for construction machinery of the present invention is as follows: The internal connection relationship and functions of the instrument controller 1 are the same as those of the prior art solution. The electrical signal of the instrument system selection switch 5 is input into the first input module 2, and the processed control signal is transmitted to the first control strategy module 3 through the internal signal bus. After the instrument control function unit 17 selects the required signal and performs operations with the control algorithm inside the function module, the processed control signal is output to the first output module 4, and finally the first output module 4 outputs an electrical signal to drive the display 12 to display signal data. The signal interaction between the instrument controller 1 and the hydraulic two-in-one controller 6 is still realized through the CAN bus.

[0054] The hydraulic two-in-one controller 6 realizes the hardware integration of the hydraulic controller and the engine controller of the prior art solution, including the hardware integration of the second input module 7, the software integration of the hydraulic control function unit 18 and the engine control function unit 19 of the second control strategy module 8, the hardware integration of the second output module 9 and the integration of some hardware common resources.

[0055] The electrical signals of the hydraulic control system selection switch, the hydraulic system sensor 13, the engine system selection switch 11, and the engine system sensor 14 are input into the second input module 7 for unified processing. The processed control signals are transmitted to the second control strategy module 8 via the internal signal bus. After the hydraulic control function unit 18 and the engine control function unit 19 select the signals they need and perform calculations with the algorithms inside the function module, they output the processed control signals to the second output module 9. Finally, the second output module 9 outputs electrical signals to drive the hydraulic system actuator 15 and the engine system actuator 16.

[0056] The main differences between the technical solution of the present invention and the prior art solution are as follows:

[0057] Not only the hardware of the original hydraulic controller and the hardware of the engine controller are integrated into one, forming the hydraulic integrated controller 6, saving some shared hardware resources (such as power control, IO resources, storage resources, etc.), but also the control functions of the hydraulic controller and the engine controller are integrated functionally and uniformly placed in the second control strategy module 8 of the hydraulic integrated controller 6, realizing the rapid transmission between the control signals of the hydraulic control function unit 18 and the engine control function unit 19, and overcoming the disadvantages of the original transmission via the CAN bus.

[0058] As Figure 3 shown, the main function of the hydraulic integrated controller 6 is to perform closed-loop control on the hydraulic pump by collecting and judging various input signals and through a series of control algorithms. Figure 3 What is shown is the logic of this control strategy.

[0059] The signal of working mode 20 is input into the instrument controller 1 by the instrument system selection switch 5. After signal processing, it is transmitted to the hydraulic control function unit 18 of the hydraulic two-in-one controller 6 through the CAN bus. The rotational speed target value 21 is determined by the hydraulic control function unit 18 according to the current state of the whole vehicle. The actual engine speed 22 is obtained by the engine control function unit 19 collecting the data of the engine system sensor 14 through the second input module 7 and processing it. The signal of the throttle knob position 23 is input into the instrument controller 1 by the instrument system selection switch 5. After signal processing, it is transmitted to the hydraulic control function unit 18 of the hydraulic two-in-one controller 6 through the CAN bus. The engine speed deviation value is obtained by subtracting the actual engine speed 22 from the rotational speed target value 21. Together with the rotational speed target value 21, it is used as an input variable to the MAPs of the heavy-duty mode 24, economy mode 25, and fine mode 26, so as to obtain the drive current value of the hydraulic pump open-loop control. The rotational speed target value 21 and the throttle knob position 23 are used as input variables to the PID27 control function to obtain the compensation value of the hydraulic pump closed-loop control. The signal of the working mode 20 is input into the mode selection switch 28, which will select a certain hydraulic pump open-loop control drive current signal in the heavy-duty mode 24, economy mode 25, or fine mode 26 and add it to the compensation value of the hydraulic pump closed-loop control to obtain the hydraulic pump closed-loop control drive current 29, thereby driving the hydraulic pump in the hydraulic system actuator 15 to work.

[0060] The working condition scenario selects the heavy-duty mode 24 in the working mode 20 and the appropriate throttle knob position 23 to carry out on-site excavation work. The rotational speed target value 21 and the deviation value between the rotational speed target value 21 and the actual engine speed 22 are used as the input to the MAP of the heavy-duty mode 24, and the drive current of the hydraulic pump open-loop control is obtained by looking up the table. The drive current data in this MAP needs to be calibrated for the whole vehicle through multiple rounds and determined in combination with the actual fuel consumption data of the whole vehicle. The rotational speed target value 21 and the throttle knob position 23 are used as the input to the PID27 control function in the heavy-duty mode 24, and the deviation value of the hydraulic pump closed-loop control in this mode is output. Since the working mode 20 selects the heavy-duty mode 24, the drive current value of the hydraulic pump open-loop control in the heavy-duty mode 24 can be added to the deviation value of the hydraulic pump closed-loop control through the mode selection switch 28 to obtain the hydraulic pump closed-loop control drive current 29 in the heavy-duty mode 24. Since the hydraulic controller (hydraulic control function unit 18) and the engine controller (engine control function unit 19) are integrated into one in hardware to form the hydraulic two-in-one controller 6, the signal interaction between the hydraulic control function unit 18 and the engine control function unit 19 is no longer limited by the transmission efficiency of the CAN bus, so that the closed-loop control of the hydraulic pump current can be achieved faster, thereby achieving the purpose of fuel saving for the whole vehicle.

[0061] The present invention integrates the original hydraulic controller hardware and engine controller hardware to form the hydraulic two-in-one controller 6 hardware. Due to the integration of functions, the parts with the same functions in the two independent controllers (such as power control function, IO resources, storage resources, sensor resources, etc.) are also reduced, thus improving the utilization rate of hardware resources. The control functions originally distributed in different controllers are thus integrated and merged into the same control function area, greatly improving the signal transmission rate and transmission quality between the two control functions (hydraulic control function and engine control function). The advantage is that the engine can quickly respond to the rotational speed demand of the hydraulic control function, and the rotational speed fluctuation range is controllable, so that the control efficiency of the hydraulic control function for the hydraulic pump is further improved, and thus the fuel saving effect of the whole vehicle is achieved.

[0062] After the hydraulic controller and the engine controller are integrated into a hydraulic two-in-one controller 6, various common hardware resources are reduced, and various signal parameters originally transmitted through the CAN bus are thus improved.

[0063] The driver selects the working mode 20 and the throttle knob gear 23 through the instrument system. The instrument controller 1 transmits these signals to the hydraulic two-in-one controller 6 through the CAN bus. The two-in-one controller collects the actual engine speed 22 signal, combines it with the input signal transmitted by the instrument controller 1 to the two-in-one controller, and outputs the drive current of the hydraulic pump through the corresponding control logic, thereby realizing the closed-loop control of the hydraulic pump.

[0064] Compared with the prior art that uses a separate hydraulic controller and collects signals such as the engine speed in the engine controller through the CAN bus to control the hydraulic pump, the proposed solution of the present application realizes the goal of the hydraulic control function and the engine control function in the same function area by integrating the two-in-one controller, enabling the hydraulic control function to obtain a fast feedback of the engine speed signal of the engine control function and a significant improvement in the transmission signal quality, and further realizing the precise control of the hydraulic pump within a small target current deviation range. Through the two-in-one integration of the controller hardware, the sharing of hardware resources such as power control, IO, and storage is realized, and the utilization rate of hardware resources is improved. Since the two-in-one controller uses fewer components and the connecting wire harnesses between the controllers are also reduced accordingly, this also indirectly reduces the probability of failure of the corresponding components.

[0065] In summary, the hydraulic two-in-one control system and method for construction machinery of the present invention has a simple and reasonable structure, improves the integration degree and signal fast response of the control function, improves the utilization rate of hardware resources, and reduces fuel consumption.

[0066] The foregoing description of the specific exemplary embodiments of the present invention is for purposes of illustration and exemplification. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is apparent that many changes and variations are possible in light of the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the invention and its practical applications, so that those skilled in the art can implement and utilize the various different exemplary embodiments of the invention, as well as various different selections and changes. The scope of the present invention is intended to be defined by the claims and their equivalents.

Claims

1. A hydraulic two-in-one control system for construction machinery, characterized in that, Including: An instrument controller, including a first input module, a first control strategy module, and a first output module that are electrically connected; An instrument system selection switch, electrically connected to the first input module of the instrument controller; A hydraulic two-in-one controller, electrically connected to the instrument controller via a CAN bus, and the hydraulic two-in-one controller includes a second input module, a second control strategy module, and a second output module that are electrically connected; A hydraulic system selection switch, electrically connected to the second input module of the hydraulic two-in-one controller; An engine system selection switch, electrically connected to the second input module of the hydraulic two-in-one controller; A hydraulic system sensor, electrically connected to the second input module of the hydraulic two-in-one controller; And A display, electrically connected to the first output module of the instrument controller.

2. The hydraulic two-in-one control system for construction machinery according to claim 1, characterized in that, It further includes an engine system sensor, electrically connected to the second input module of the hydraulic two-in-one controller.

3. The hydraulic two-in-one control system for construction machinery according to claim 1, characterized in that, It further includes a hydraulic system actuator, electrically connected to the second output module of the hydraulic two-in-one controller.

4. The hydraulic two-in-one control system for construction machinery according to claim 1, characterized in that, It further includes an engine system actuator, electrically connected to the second output module of the hydraulic two-in-one controller.

5. The hydraulic two-in-one control system for construction machinery according to claim 1, wherein, The first control strategy module includes an instrument control function unit.

6. The hydraulic two-in-one control system for construction machinery according to claim 1, wherein The second control strategy module includes a hydraulic control function unit and an engine control function unit that are electrically connected.

7. A control method for a hydraulic two-in-one control system of construction machinery, based on the hydraulic two-in-one control system of construction machinery according to any one of claims 1 to 6, characterized in that, The control method of the hydraulic two-in-one control system for construction machinery includes: The instrument controller obtains a working mode signal and sends the working mode signal to the hydraulic two-in-one controller via the CAN bus; The hydraulic two-in-one controller determines a speed target value according to the current state of the whole vehicle; The hydraulic two-in-one controller collects data sensed by the engine system to obtain the actual engine speed; The instrument controller obtains a throttle knob gear signal and sends the throttle knob gear signal to the hydraulic two-in-one controller via the CAN bus; Obtain an engine speed deviation value, and use the engine speed deviation value and the speed target value as input variables to input into the MAP of the heavy-duty mode, economy mode, and fine mode, so as to obtain the drive current value of the open-loop control of the hydraulic pump; Use the speed target value and the throttle knob gear as input variables to input into the PID to obtain the compensation value of the closed-loop control of the hydraulic pump; Obtain the drive current of the closed-loop control of the hydraulic pump, so as to drive the hydraulic pump in the hydraulic system actuator to work.

8. The control method of the hydraulic two-in-one control system for construction machinery according to claim 7, characterized in that, The engine speed deviation value is obtained by subtracting the actual engine speed from the speed target value.

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