Hydraulic system and hydraulic control method based on multi-execution-state data collection

Abstract

Disclosed in the present invention is a hydraulic control method based on multi-execution-state data collection. The method comprises: acquiring identity information of a driver; measuring performance parameters of a hydraulic system in each execution state; after repeating n times, recording and storing the operation frequency, and an average value of performance parameters of the hydraulic system; outputting a control value; establishing a hydraulic control model for when a forklift is unloaded, and a hydraulic control model for when the forklift is loaded; and when it is identified that the driver is the same person, the hydraulic system of the forklift autonomously controlling the operation of the forklift automatically according to a hydraulic control model output. In the present invention, a hydraulic control model is established to control the rotating speed of a pump electric motor, without the active control from a driver, and the driver manually controls a forklift control lever to realize the startup and shutdown of a hydraulic system, such that the requirement of operation efficiency can be met, and the goal of energy saving can also be achieved.

Description

Hydraulic system and control method based on multi-execution state data collection Technical Field

[0001] The present invention belongs to the technical field of forklifts, and in particular relates to a self-feedback energy control system and a control method of a heavy-duty electric forklift hydraulic system based on multi-execution state data collection. Background Art

[0002] Heavy-duty electric forklifts generally refer to those weighing over 6 tons. They use batteries to drive the motor and hydraulic system, enabling travel and loading and unloading. Due to their inherent weight, and the added weight of a load, heavy-duty electric forklifts require significant power. However, due to the space occupied by each major system within the overall layout, the power battery cannot be designed to be very large, limiting its battery life.

[0003] Most forklift operations involve varying loads or maintaining a fixed load within a certain range below the rated load. However, since forklifts are operated by different drivers at different times, each person has unique operating habits, such as the amount of force applied to the handles, pedals, and accelerator, as well as the speed, duration, and other factors. This requires the forklift's vehicle control unit (VCU) to re-strategize hydraulic performance strategies for each operation. For example, the pump motor speed, hydraulic pump oil output, and hydraulic oil pressure are all different. This results in hydraulic performance being completely controlled by the driver, resulting in a high VCU workload and a loss of energy efficiency.

[0004] The hydraulic control model of the present invention collects and processes the hydraulic performance parameters of different drivers in different execution states, proposes an optimal control strategy for the hydraulic system, and autonomously outputs the required hydraulic performance under the set expected execution state. At this time, the driver controls the hydraulic action only as a signal input and does not participate in the motor speed control. It enters the autonomous control state, and the hydraulic action output of the entire vehicle best fits the current driver's working habits.

[0005] The present invention combines facial recognition function with the ability to independently collect the independent operating habits of multiple people on the entire machine, record the entire process of each driver's driving control habits into a data dot matrix, and then automatically switch the person's operating habit recommendation mode according to the driver's identity, identify the set point that triggers the control habit, and implement active control. Summary of the Invention

[0006] The purpose of the present invention is to provide a hydraulic system and control method based on multi-execution state data collection, thereby maximizing the collection of operating habits and solidifying the operating state of each actuator cylinder into an operating state that not only meets operating efficiency requirements, but also saves energy and adapts to the driver's habits.

[0007] The specific technical solutions of the present invention are as follows:

[0008] A hydraulic control method based on multi-execution state data collection includes the following steps:

[0009] S1. Obtain the driver's identity information;

[0010] S2. When the forklift is unloaded, operate the forklift handle to make each actuator cylinder enter the execution state in turn, and then test the performance parameters of the hydraulic system in each execution state respectively;

[0011] S3. After repeating n times, record and store the operation frequency of the forklift in each execution state and the average value of the hydraulic system performance parameters;

[0012] S4. Compare the average value of the operating speed in the hydraulic system performance parameter with a preset value. If the difference is greater than a specified value, replace the average value with the preset value and output it as a control value.

[0013] S5. After processing the control value in step S4, the output current or voltage signal is fed back to the pump motor controller to control the speed of the pump motor; thereby establishing a hydraulic control model for the forklift when it is unloaded;

[0014] S6. Load the forklift with cargo of different weights, and build a hydraulic control model for the forklift under load, as in steps S2-S5.

[0015] S7. When the driver is identified as the same person in step S1, once the driver operates the forklift handle, the hydraulic system of the forklift automatically controls the operation of the forklift according to the hydraulic control model output in step S5 or S6.

[0016] In a further solution, the hydraulic control model includes operation frequency, average values ​​of performance parameters of the hydraulic system, control values, and rotational speed of the pump motor.

[0017] A further solution is that in step S7, once the driver operates the forklift handle, the operation frequency of each execution state of the forklift is synchronously detected. When the operation frequency is 20% less than the operation frequency in the hydraulic control model for three consecutive times, the hydraulic control model is released and the driver needs to manually control the forklift hydraulic system.

[0018] In a further solution, in step S7, after the driver operates the forklift handle, the forklift load is first detected to determine whether it is empty or loaded, and then the forklift operation is autonomously controlled according to the corresponding hydraulic control model output.

[0019] In a further solution, in step S2, the executing cylinders include a lifting cylinder, a tilting cylinder and a side shifting cylinder; and the executing states include the forklift in the lifting, lowering, forward tilting, backward tilting, left shifting and right shifting operating states.

[0020] In a further solution, in step S2, the hydraulic system performance parameters include the oil pressure, load, operating time, operating speed and cylinder stroke of the execution cylinder.

[0021] In a further solution, the prescribed values ​​in step S4 are: the prescribed value of the lifting speed is ±30 mm / s, the prescribed value of the tilting speed is 1.2° / s, and the prescribed value of the lateral movement speed is ±9 mm / s.

[0022] In a further solution, a pressure sensor is installed in the execution cylinder for detecting oil pressure; and the running speed is calculated based on the running time and stroke of the execution cylinder.

[0023] Another object of the present invention is to provide a hydraulic system for realizing the hydraulic control method as described above, comprising a forklift handle, a vehicle controller, a pump motor, and a hydraulic system that uses a gear pump to deliver hydraulic oil to the lifting cylinder, tilt cylinder, and side shift cylinder through a multi-way valve. The lifting cylinder, tilt cylinder, and side shift cylinder are each equipped with a pressure sensor for detecting oil pressure, and the forklift handle is equipped with a photoelectric sensor for detecting its operation frequency; the signal ends of the photoelectric sensor and the pressure sensor are both connected to the input end of the vehicle controller, and the output end of the vehicle controller is connected to the pump motor through a pump motor controller.

[0024] The present invention detects the oil pressure of each actuator cylinder through a pressure sensor and determines whether the forklift is loaded by the change in oil pressure. The oil pressure of the actuator cylinder is proportional to the load size, so the load of the forklift can be calculated, and its lifting speed can be calculated according to the stroke and time of the actuator cylinder.

[0025] The present invention uses a photoelectric sensor to detect the operation frequency of the forklift handle operated by the operator, and compares it with the operation frequency in the hydraulic control model. If it is close, the forklift is directly controlled according to the output of the hydraulic control model; if the operation frequency is 20% less than the operation frequency in the hydraulic control model after three consecutive times, the hydraulic control model is released and the driver needs to manually control the forklift hydraulic system.

[0026] This invention controls the pump motor speed by establishing a hydraulic control model, eliminating the need for driver-initiated control. Manual control of the forklift handle effectively turns the hydraulic system on and off, achieving both operational efficiency and energy conservation. This approach achieves intelligent identification, precise control, and proactive output of hydraulic performance tailored to the individual driver's operating habits, resulting in optimal control, maximum energy savings, and extended battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG1 is a block diagram of the hydraulic system of the present invention;

[0028] FIG2 is a block diagram of the control method of the present invention. Modes for Carrying Out the Invention

[0029] The technical solutions of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. It is obvious that the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] Example 1:

[0031] As shown in FIG2 , a hydraulic control method based on multi-execution state data collection includes the following steps:

[0032] S1. Obtain the driver's identity information;

[0033] S2. When the forklift is unloaded, operate the forklift handle to make each actuator cylinder enter the execution state in turn, and then test the performance parameters of the hydraulic system in each execution state respectively;

[0034] S3. After repeating n times, record and store the operation frequency of the forklift in each execution state and the average value of the hydraulic system performance parameters;

[0035] In this embodiment, the number of repetitions n is preferably 10-15 times for each cylinder to perform the action.

[0036] S4. Compare the average value of the operating speed in the hydraulic system performance parameter with a preset value. If the difference is greater than a specified value, replace the average value with the preset value and output it as a control value.

[0037] The specified values ​​are: the specified value of lifting speed is ±30mm / s, the specified value of tilting speed is 1.2° / s, and the specified value of lateral movement speed is ±9mm / s.

[0038] That is, when the forklift is performing a lifting operation, if the difference between the average lifting speed and the preset value is greater than ±30mm / s, the average value is output as the control value; otherwise, the preset value is output as the control value;

[0039] When the forklift performs tilting motion, if the difference between the average value of the tilting speed and the preset value is greater than 1.2° / s, the average value is output as the control value; otherwise, the preset value is output as the control value;

[0040] When the forklift performs lateral movement, if the difference between the average value of the lateral movement speed and the preset value is greater than ±9mm / s, the average value is output as the control value; otherwise, the preset value is output as the control value.

[0041] S5. After processing the control value in step S4, the output current or voltage signal is fed back to the pump motor controller to control the speed of the pump motor; thereby establishing a hydraulic control model for the forklift when it is unloaded;

[0042] S6. Load the forklift with cargo of different weights, and build a hydraulic control model for the forklift under load, as in steps S2-S5.

[0043] S7. When the driver is identified as the same person in step S1, once the driver operates the forklift handle, the hydraulic system of the forklift automatically controls the operation of the forklift according to the hydraulic control model output in step S5 or S6.

[0044] When the driver operates the forklift handle, the system first detects whether the forklift is empty or loaded, and then autonomously controls the forklift according to the corresponding hydraulic control model output. This means there is a one-to-one correspondence between the hydraulic control model and the forklift load.

[0045] Once the driver operates the forklift handle, the forklift's operating frequency for each execution state is detected simultaneously. If the operating frequency is 20% less than the operating frequency in the hydraulic control model for three consecutive times, the hydraulic control model is released and the driver must manually control the forklift's hydraulic system. In other words, the real-time performance parameter output of the forklift's hydraulic system is achieved through manual control.

[0046] In this embodiment, the hydraulic control model includes the operation frequency, the average value of the performance parameters of the hydraulic system, the control value, and the speed of the pump motor.

[0047] The execution cylinders include the lifting cylinder, tilting cylinder and side shifting cylinder; the execution states include the forklift's lifting, lowering, forward tilting, backward tilting, left shifting and right shifting operating states.

[0048] Hydraulic system performance parameters include the oil pressure, load, operating time, operating speed and cylinder stroke of the actuator cylinder.

[0049] In a further solution, a pressure sensor is installed in the execution cylinder for detecting oil pressure; and the running speed is calculated based on the running time and stroke of the execution cylinder.

[0050] For example, when the lifting cylinder is in the lifting action and the driver operates the forklift handle to lift the goods, the pump motor starts and drives the gear pump to supply oil to the multi-way valve, and then supplies oil to the actuator lifting cylinder to lift the goods. The lifting cylinder is equipped with a pressure sensor Y1, which detects the lifting pressure Y11, Y12, Y13...Y1n in real time. The average oil pressure of the lifting cylinder is: , and record and calculate the mean forklift load G11, G12, G13...G1n one by one, then Then calculate the lifting speed V11, V12, V13...V1n of the lifting cylinder according to the time and cylinder stroke, then , the above n is the number of times.

[0051] The average value of the above hydraulic system performance parameters is compared with the preset value, and the final control value is output to control the operation, that is, the output current or voltage signal is fed back to the pump motor controller to control the speed of the pump motor; based on this, a hydraulic control model of the forklift during lifting is established, which includes the operation frequency, the average value of the hydraulic system performance parameters, the control value, and the speed of the pump motor.

[0052] Similarly, hydraulic control models are established for the forklift when it is empty or loaded and when it is descending, tilting forward, tilting backward, moving left, and moving right.

[0053] According to the control block diagram in Figure 2, the driver operates the forklift handle, and the vehicle controller starts the hydraulic system after receiving the control signal. The automatic control of the forklift is achieved by establishing the hydraulic control model under each execution state.

[0054] Through the above-mentioned control method, the vehicle controller of the present invention identifies and outputs a control method that is consistent with the current driver's habitual control, thereby reducing unnecessary high-performance output manipulation, effectively reducing the energy consumption of the entire hydraulic system, and increasing the battery life of the power battery.

[0055] Example 2:

[0056] As shown in Figure 1, a hydraulic system for implementing the hydraulic control method as described above includes a forklift handle 1, a vehicle controller 10, a pump motor 2, and a hydraulic system that uses a gear pump 4 to transport hydraulic oil to a lifting cylinder 6, a tilting cylinder 7, and a side-shifting cylinder 8 through a multi-way valve 5. The lifting cylinder 6, the tilting cylinder 7, and the side-shifting cylinder 8 are all equipped with a pressure sensor 9 for detecting the oil pressure, and the forklift handle 1 is equipped with a photoelectric sensor for detecting its operation frequency; the signal ends of the photoelectric sensor and the pressure sensor 9 are both connected to the input end of the vehicle controller 10, and the output end of the vehicle controller 10 is connected to the pump motor 2 through the pump motor controller 3.

[0057] Although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A hydraulic control method based on multi-execution state data collection, characterized by: The following steps are involved: S1. Obtain the driver's identity information; S2. When the forklift is unloaded, operate the forklift handle to make each actuator cylinder enter the execution state in turn, and then test the performance parameters of the hydraulic system in each execution state respectively; S3. After repeating n times, record and store the operation frequency of the forklift in each execution state and the average value of the hydraulic system performance parameters; S4. Compare the average value of the operating speed in the hydraulic system performance parameter with a preset value. If the difference is greater than a specified value, replace the average value with the preset value and output it as a control value. S5. After processing the control value in step S4, the output current or voltage signal is fed back to the pump motor controller to control the speed of the pump motor; thereby establishing a hydraulic control model for the forklift when it is unloaded; S6. Load the forklift with cargo of different weights, and build a hydraulic control model for the forklift under load, as in steps S2-S5. S7. When the driver is identified as the same person in step S1, once the driver operates the forklift handle, the hydraulic system of the forklift automatically controls the operation of the forklift according to the hydraulic control model output in step S5 or S6.

2. The hydraulic control method according to claim 1, characterized in that: The hydraulic control model includes operation frequency, average values of performance parameters of the hydraulic system, control values, and rotation speed of the pump motor.

3. The hydraulic control method according to claim 1, wherein: In step S7, once the driver operates the forklift handle, the operation frequency of the forklift in each execution state is synchronously detected. When the operation frequency is 20% less than the operation frequency in the hydraulic control model for three consecutive times, the hydraulic control model is released and the forklift hydraulic system is manually controlled.

4. The hydraulic control method according to claim 1, wherein: After the driver operates the forklift handle, he first detects whether the forklift load is empty or loaded with cargo, and then autonomously controls the forklift operation according to the corresponding hydraulic control model output.

5. The hydraulic control method according to claim 1, wherein: The execution cylinders include the lifting cylinder, tilting cylinder and side shifting cylinder; the execution states include the forklift's lifting, lowering, forward tilting, backward tilting, left shifting and right shifting operating states.

6. The hydraulic control method according to claim 1, characterized in that: Hydraulic system performance parameters include the oil pressure, load, operating time, operating speed and cylinder stroke of the actuator cylinder.

7. The hydraulic control method according to claim 6, characterized in that: A pressure sensor is installed in the execution oil cylinder for detecting oil pressure; the running speed is calculated based on the running time and stroke of the execution oil cylinder.

8. The hydraulic control method according to claim 6, characterized in that: The prescribed values in step S4 are: the prescribed value of the lifting speed is ±30 mm / s, the prescribed value of the tilting speed is 1.2° / s, and the prescribed value of the lateral movement speed is ±9 mm / s.

9. A hydraulic system for implementing the hydraulic control method according to any one of claims 1 to 8, comprising a forklift handle (1), a vehicle controller (10), a pump motor (2), and a hydraulic system for delivering hydraulic oil to a lifting cylinder (6), a tilting cylinder (7), and a side shift cylinder (8) through a gear pump (4) via a multi-way valve (5), characterized in that: The lifting cylinder (6), tilting cylinder (7), and side shifting cylinder (8) are each equipped with a pressure sensor (9) for detecting oil pressure, and the forklift handle (1) is equipped with a photoelectric sensor for detecting the frequency of operation thereof; the signal ends of the photoelectric sensor and the pressure sensor (9) are both connected to the input end of the vehicle controller (10), and the output end of the vehicle controller (10) is connected to the pump motor (2) via the pump motor controller (3).

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