Intelligent bidirectional speed regulation hydraulic cylinder control system and control method thereof

Abstract

The invention discloses an intelligent bidirectional speed regulation hydraulic cylinder control system and a control method thereof. The hydraulic control system comprises a hydraulic cylinder, a proportional speed regulation valve, an electromagnetic proportional overflow valve, a one-way valve, a hydraulic control one-way valve, a reversing valve, a pressure switch, a button switch, a pressure sensor and a control unit. When oil enters the left side of the hydraulic cylinder, the control unit outputs two paths of control signals according to extension control requirements, the two paths of control signals control the proportional speed regulating valve and the electromagnetic proportional overflow valve respectively, and the proportional speed regulating valve and the electromagnetic proportional overflow valve control the extension speed and thrust of the hydraulic cylinder according to the control signals. The control unit controls the retraction speed and tension of the hydraulic cylinder according to the same principle, so that the movement speed and pressure of the hydraulic cylinder in two directions are adjustable; the system can also automatically adjust the movement speed and the working pressure according to the load change; the hydraulic system can achieve remote intelligent speed regulation and pressure regulation, and is simple in structure, safe, reliable and high in automation degree.

Description

Technical Field

[0001] The invention relates to the field of environmental resource drilling equipment, and in particular to an intelligent two-way speed regulating hydraulic cylinder control system and a control method thereof. Background Art

[0002] The groundwater sampling and repair integrated drilling rig needs to pressurize and lift the working device, and the pressurization and lifting generally have speed regulation functions. Chinese patent CN112594235B discloses a technical solution that can adjust the speed and working pressure of pressurization and lifting according to the working conditions, combining the pressurization speed regulation circuit and the lifting speed regulation circuit into one, saving space and simplifying installation. However, this solution has the following shortcomings: First, since the pressurization speed control circuit and the lifting speed control circuit are combined into one, the proportional speed control valve and the electromagnetic proportional relief valve are shared by the two circuits. After the drilling rig is pressurized, it is necessary to clear the original parameters of the proportional speed control valve and the electromagnetic proportional relief valve, and then set the combined parameters of the proportional speed control valve and the electromagnetic proportional relief valve respectively to ensure that the operating speed and working pressure of the hydraulic cylinder can meet the needs of the lifting process respectively, and vice versa. Repeatedly setting and clearing parameters is time-consuming and inefficient. Secondly, the oil at the outlet of the electromagnetic proportional relief valve needs to return to the oil tank separately, resulting in the need to provide three oil pipes for oil supply to the entire system, with complicated pipelines and low system reliability. Thirdly, if the load changes during pressurization and lifting, the system cannot automatically adjust according to the load changes, and there will be jamming or shutdown. Finally, pressurization and lifting cannot run automatically and continuously, the system has a low degree of automation, and the workers' operation is cumbersome. Summary of the invention

[0003] The purpose of the present invention is to automatically set control parameters through the system, thereby adjusting the movement speed and working pressure of the hydraulic cylinder, and at the same time having adaptive ability, and can automatically adjust the movement speed of the hydraulic cylinder according to the load.

[0004] The present invention discloses an intelligent two-way speed regulating hydraulic cylinder control system, comprising a hydraulic cylinder, two button switches, two pressure switches, two hydraulically controlled one-way valves, six one-way valves, an electromagnetic reversing reversing valve, an electromagnetic proportional relief valve, a proportional speed regulating valve, a pressure sensor and a control unit; wherein the two hydraulically controlled one-way valves are respectively: a first hydraulically controlled one-way valve 11 and a second hydraulically controlled one-way valve 13; wherein the six one-way valves are respectively: a first one-way valve 9, a second one-way valve 4, a third one-way valve 8, a fourth one-way valve 5, a fifth one-way valve 16, and a sixth one-way valve 15;

[0005] The control unit includes: input terminal 13-2, output terminal 13-3 and analog input and output module 13-1; two button switches are: start button SB1 and stop button SB2, the start button SB1 is connected to I0.2 on the input terminal 13-2, and the stop button SB2 is connected to I0.3 on the input terminal 13-2; two pressure switches are: left pressure switch 12 and right pressure switch 2, the left pressure switch 12 is connected to I0.0 on the input terminal 13-2, and the right pressure switch 2 is connected to I0.1 on the input terminal 13-2;

[0006] The analog input and output module 13-1 has 1 input signal wiring terminal and 2 output signal wiring terminals; the wiring terminals 0+ and 0- of the analog input and output module 13-1 are connected to the pressure sensor 14; the first wiring terminals 0M and 0 of the wiring terminals of the analog input and output module 13-1 are connected to the coil of the proportional speed regulating valve 10, and the second wiring terminals 1M and 1 are connected to the coil of the electromagnetic proportional overflow valve 7;

[0007] The electromagnetic reversing valve has two coils: a left reversing valve coil 6-1 and a right reversing valve coil 6-2. The two coils are connected to the output terminal 13-3 of the control unit.

[0008] As a further improvement of the present invention, the input terminals on the control unit are connected to the start button SB1 and the stop button SB2.

[0009] The present invention adopting the above technical solution has the following beneficial effects compared with the prior art:

[0010] 1. The running speed and working pressure of the hydraulic cylinder in two moving directions can be adjusted. The pressurization circuit and the lifting circuit are combined into one. The two circuits share a set of proportional speed regulating valves and electromagnetic proportional relief valves to adjust the movement speed and working pressure of the hydraulic cylinder, saving space and simple installation;

[0011] 2. The parameters of the proportional speed regulating valve and electromagnetic proportional relief valve in the pressurization and lifting process are automatically set. The parameters are set by the control unit, and there is no need to manually set them at the equipment accessories. Since the parameters in the pressurization and lifting processes are different, it is necessary to repeatedly set the parameters during the entire movement process. The control unit automatically sets the parameters, which reduces the labor intensity of workers and improves the work efficiency of the system;

[0012] 3. The entire system only needs two oil pipes for oil supply, one pressure oil pipe and one oil return pipe to the oil tank. The system's piping system is simple;

[0013] 4. During the pressurization and lifting process, once the load changes, the control system can automatically adjust the proportional speed regulating valve and electromagnetic proportional relief valve through logical reasoning according to the load change to ensure that the movement speed and working pressure of the hydraulic cylinder can meet the requirements;

[0014] 5. The pressurization process and the lifting process can run back and forth continuously and automatically, and switch automatically, with a high degree of automation and a small operating burden on workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the hydraulic system of the present invention;

[0016] Figure 2 It is a schematic diagram of the control system structure of the present invention;

[0017] Figure 3 It is a schematic diagram of the automatic load adjustment process of the present invention.

[0018] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0019] In the figure: 1-hydraulic cylinder, 2-right pressure switch, 3-second hydraulically controlled one-way valve, 4-second one-way valve, 5-fourth one-way valve, 6-electromagnetic reversing valve, 6-1-left coil of reversing valve, 6-2-right coil of reversing valve, 7-electromagnetic proportional overflow valve, 8-third one-way valve, 9-first one-way valve, 10-proportional speed control valve, 11-first hydraulically controlled one-way valve, 12-left pressure switch, 13-control unit, 13-1-analog input and output module, 13-2-input terminal, 13-3-output terminal, 14-pressure sensor, 15-sixth one-way valve, 16-fifth one-way valve. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the specific drawings.

[0021] 1. System structure description

[0022] Combination Figure 1 and Figure 2 , the intelligent two-way speed-regulating hydraulic cylinder control system is further described, the system includes: a hydraulic cylinder, two button switches, two pressure switches, two hydraulically controlled one-way valves, six one-way valves, an electromagnetic reversing reversing valve, an electromagnetic proportional overflow valve, a proportional speed regulating valve, a pressure sensor and a control unit; the two hydraulically controlled one-way valves are respectively a first hydraulically controlled one-way valve 11 and a second hydraulically controlled one-way valve 3; the six one-way valves are respectively a first one-way valve 9, a second one-way valve 4, a third one-way valve 8, a fourth one-way valve 5, a fifth one-way valve 16, and a sixth one-way valve 15.

[0023] The specific oil circuit connections of the hydraulic part are as follows:

[0024] The inlet of the proportional speed regulating valve 10 is connected to the inlet of the electromagnetic proportional relief valve 7, the outlet of the electromagnetic proportional relief valve 7 is connected to the inlets of the third check valve 8 and the fourth check valve 5, the inlet of the proportional speed regulating valve 10 is simultaneously connected to the outlets of the first check valve 9 and the second check valve 4; the outlet of the proportional speed regulating valve 10 is simultaneously connected to the outlets of the first hydraulically controlled check valve 11 and the second hydraulically controlled check valve 3;

[0025] The inlet of the first hydraulically controlled one-way valve 11 is in communication with the left chamber of the hydraulic cylinder 1, and the inlet of the second hydraulically controlled one-way valve 3 is in communication with the right chamber of the hydraulic cylinder 1 at the same time. The hydraulic control port of the first hydraulically controlled one-way valve 11 is in communication with the port A of the electromagnetic reversing directional valve 6, and the hydraulic control port of the second hydraulically controlled one-way valve 3 is in communication with the port B of the electromagnetic reversing directional valve 6;

[0026] The inlet of the first one-way valve 9 is communicated with the A port of the electromagnetic reversing reversing valve 6, the inlet of the second one-way valve 4 is communicated with the B port of the electromagnetic reversing reversing valve 6, the outlet of the third one-way valve 8 is communicated with the A port of the electromagnetic reversing reversing valve 6, the outlet of the fourth one-way valve 5 is communicated with the B port of the electromagnetic reversing reversing valve 6, the outlet of the fifth one-way valve 16 is communicated with the A port of the electromagnetic reversing reversing valve 6, the inlet of the fifth one-way valve 16 is communicated with the left chamber of the hydraulic cylinder 1, the outlet of the sixth one-way valve 15 is communicated with the B port of the electromagnetic reversing reversing valve 6, and the inlet of the sixth one-way valve 15 is communicated with the right chamber of the hydraulic cylinder 1;

[0027] The pressure sensor 14 is connected to the inlet of the proportional speed regulating valve 10;

[0028] The left pressure switch 12 is connected to the left chamber of the hydraulic cylinder 1, and the right pressure switch 2 is connected to the right chamber of the hydraulic cylinder 1;

[0029] The P port of the electromagnetic reversing reversing valve 6 is connected to the pressure oil, and the T port is connected to the oil tank; 2) The specific circuit connection of the control part is as follows:

[0030] The control unit includes: an input terminal 13-2, an output terminal 13-3 and an analog input and output module 13-1; two button switches are: a start button SB1 and a stop button SB2, the start button SB1 is connected to I0.2 of the input terminal 13-2, and the stop button SB2 is connected to I0.3 of the input terminal 13-2; two pressure switches are: a left pressure switch 12 and a right pressure switch 2, the left pressure switch 12 is connected to I0.0 of the input terminal 13-2, and the right pressure switch 2 is connected to I0.1 of the input terminal 13-2; there is 1 input signal wiring terminal and 2 output signal wiring terminals on the analog input and output module 13-1; the wiring terminals 0+ and 0- of the analog input and output module 13-1 are connected to the pressure sensor 14;

[0031] The first wiring terminal 0M and 0 of the analog input and output module 13-1 are connected to the coil of the proportional speed regulating valve 10, and the second wiring terminal 1M and 1 are connected to the coil of the electromagnetic proportional relief valve 7;

[0032] The hydraulically controlled reversing valve has two coils, namely, the left reversing valve coil 6-1 and the right reversing valve coil 6-2. The two coils are connected to Q0.0 and Q0.1 on the output terminal 13-3 of the control unit.

[0033] The present invention can realize the following functions: 1) bidirectionally adjust the operating speed and working pressure of the pressurization and lifting of the working device; 2) automatically set the parameters of the proportional speed control valve and the electromagnetic proportional relief valve in the pressurization and lifting process without manual intervention; 3) the entire system only needs two oil pipes, and the pipelines are simple; 4) when the load changes, the operating speed and working pressure can be automatically adjusted according to the load changes; 5) pressurization and lifting can be automatically operated back and forth continuously, with a high degree of automation and a small operating burden on workers.

[0034] 2. Specific process description of control method

[0035] Combination Figure 3 , Figure 2 and Figure 1 The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system is described as follows:

[0036] 1) The piston rod of hydraulic cylinder 1 extends, and the control method includes the following steps:

[0037] ① The control unit output terminal 13-3 outputs a control signal, the left coil 6-1 of the reversing valve is energized, and the electromagnetic reversing valve switches to the left position to work; the pressure oil passes through the A port of the electromagnetic reversing valve 6, the first non-return valve 9, the proportional speed regulating valve 10, and the first hydraulic control non-return valve 11 to enter the left chamber of the hydraulic cylinder to supply oil to the hydraulic cylinder; the oil pressure in the right chamber of the hydraulic cylinder passes through the sixth non-return valve 15 and the B port of the electromagnetic reversing valve 6 to return to the oil tank; the oil at the outlet of the electromagnetic proportional relief valve 7 passes through the fourth non-return valve 5 and the B port of the electromagnetic reversing valve 6 to return to the oil tank;

[0038] ② During the extension process of the hydraulic cylinder, according to the pre-set program, the control unit outputs the first analog signal to control the opening size of the proportional speed regulating valve 10, thereby adjusting the extension speed of the hydraulic cylinder, and the control unit outputs the second analog signal to control the set pressure of the proportional relief valve, thereby adjusting the working pressure of the hydraulic cylinder;

[0039] ③ When the hydraulic cylinder extends to the end point, the pressure on the left side of the hydraulic cylinder increases, triggering the left pressure switch 12 to generate a signal. The signal enters the control unit through the control unit input terminal 13-2. The control unit generates a control signal, which is output to the right side solenoid 6-2 of the reversing valve through the output terminal 13-3. The reversing valve changes to the right position, and the hydraulic oil flows out from the B port of the electromagnetic reversing valve and enters the right side of the hydraulic cylinder, and the hydraulic cylinder retracts.

[0040] 2) The piston rod of hydraulic cylinder 1 retracts, and the control method includes the following steps:

[0041] ① The control unit output terminal 13-3 outputs a control signal, the right coil 6-2 of the reversing valve is energized, and the electromagnetic reversing valve changes to the right position to work; the pressure oil passes through the B port of the electromagnetic reversing valve 6, the second one-way valve 4, the proportional speed regulating valve 10, and the second hydraulic one-way valve 3 to enter the right chamber of the hydraulic cylinder to supply oil to the hydraulic cylinder; the oil in the left chamber of the hydraulic cylinder passes through the fifth one-way valve 16 and the A port of the electromagnetic reversing valve 6 to return to the oil tank; the oil at the outlet of the electromagnetic proportional relief valve 7 passes through the third one-way valve 8 and the A port of the electromagnetic reversing valve 6 to return to the oil tank;

[0042] ② During the retraction process of the hydraulic cylinder, according to the pre-set program, the control unit outputs the first analog signal to control the opening size of the proportional speed regulating valve 10, thereby adjusting the retraction speed of the hydraulic cylinder, and the control unit outputs the second analog signal to control the set pressure of the proportional relief valve, thereby adjusting the working pressure of the hydraulic cylinder;

[0043] ③ When the hydraulic cylinder retracts to the end point, the pressure on the right side of the hydraulic cylinder increases, triggering the right side pressure switch 2. The right side pressure switch generates a signal, which enters the control unit through the control unit input terminal 13-2. The control unit generates a control signal, which is output to the left coil 6-1 of the reversing valve through the output terminal 13-3. The reversing valve changes to the left position, and the hydraulic oil flows out from the reversing valve A port and enters the left side of the hydraulic cylinder, and the hydraulic cylinder extends.

[0044] 3) Automatic reciprocating operation, the control method includes the following steps:

[0045] ① Press the start button SB1, the control unit 13 sends a signal, the left coil 6-1 of the reversing valve is energized, the electromagnetic reversing valve 6 changes to the left position, and the hydraulic cylinder 1 extends;

[0046] ② When the hydraulic cylinder moves to the end point, the left pressure switch 12 sends a signal, the control unit 13 controls the right coil 6-2 of the reversing valve to be energized, and the hydraulic cylinder 1 retracts. When it moves to the end point, the right pressure switch 2 sends a signal, the control unit 13 controls the left coil 6-1 of the reversing valve to be energized, and the hydraulic cylinder extends again;

[0047] ③ Repeat this process to achieve automatic reciprocating operation.

[0048] 4) Bidirectional speed regulation and voltage regulation, the control method is as follows:

[0049] When the hydraulic cylinder extends or retracts, the control unit 13 outputs two control signals respectively to adjust the opening size of the proportional speed control valve 10, control the flow of hydraulic oil, and thus control the movement speed of the hydraulic cylinder, and adjust the set pressure of the electromagnetic proportional relief valve 7 to control the pressure of the system, that is, adjust the working pressure of the hydraulic cylinder, thereby realizing speed control and pressure control in both directions of extension and retraction of the hydraulic cylinder.

[0050] 5) The control unit automatically adjusts according to load fluctuations, combined with Figure 3 , the control method is described as follows:

[0051] ① After the hydraulic cylinder reaches the top, the working pressure rises to the set value of the pressure switch, and the control unit 13 controls the electromagnetic reversing valve 6 to change direction. The control unit 13 counts the running time and compares it with the standard running time;

[0052] ② If the running time is less than the standard time, the working pressure is further compared with the set pressure of the proportional relief valve 7. If the two are equal, the opening of the proportional speed regulating valve 10 is reduced by Δx and the data is stored to slow down the running speed; if the former is less than the latter, the working pressure of the electromagnetic proportional relief valve 7 is reduced by ΔP and the data is stored to lower the working pressure;

[0053] ③ If the running time is greater than the standard time, further check whether the working pressure has a sudden change; if there is a sudden change, the working pressure of the electromagnetic proportional relief valve 7 increases by ΔP and stores the data, and the working pressure is increased; if there is no sudden change, further compare the working pressure with the set pressure of the proportional relief valve 10; if the two are equal, the opening of the proportional speed regulating valve 10 increases by Δx and stores the data to speed up the running speed; if the former is greater than the latter, the working pressure of the electromagnetic proportional relief valve 7 increases by ΔP and stores the data, and the working pressure is increased;

[0054] ④ After increasing the working pressure of the electromagnetic proportional relief valve 7, it is necessary to compare the working pressure with the set pressure of the proportional relief valve 7 again; if the two are equal, the hydraulic cylinder starts to operate normally; if the former is greater than the latter, the hydraulic cylinder does not move and it is necessary to enter the next cycle process and continue to increase the working pressure of the proportional relief valve 7.

[0055] In summary, the intelligent bidirectional speed regulating hydraulic cylinder control system and control method of the present invention solve the following problems existing in the prior art:

[0056] 1. The operating speed and working pressure parameters of the hydraulic cylinder's pressurization and lifting process need to be set repeatedly manually, which is inefficient and prone to errors;

[0057] 2. The system oil supply pipeline is complicated;

[0058] 3. When the load changes, the hydraulic cylinder movement speed becomes unstable, stuck, or even stops completely; 4. The two processes of pressurization and lifting need to be switched manually, which puts a heavy burden on workers and reduces efficiency.

[0059] It is to be understood that the implementation of the above control system and control method is only an exemplary embodiment adopted to illustrate the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered as the protection scope of the present invention.

Claims

1. An intelligent two-way speed regulating hydraulic cylinder control system, characterized in that: include: One hydraulic cylinder, two push button switches, two pressure switches, two hydraulically controlled one-way valves, six one-way valves, one solenoid directional control valve, one solenoid proportional relief valve, one proportional speed regulating valve, one pressure sensor and one control unit; The two hydraulically controlled one-way valves are: a first hydraulically controlled one-way valve (11) and a second hydraulically controlled one-way valve (3); The six one-way valves are: a first one-way valve (9), a second one-way valve (4), a third one-way valve (8), a fourth one-way valve (5), a fifth one-way valve (16), and a sixth one-way valve (15); The control unit (13) comprises: an input terminal (13-2), an output terminal (13-3) and an analog input and output module (13-1); The two button switches are: a start button SB1 and a stop button SB2, the start button SB1 is connected to the input terminal (13-2) I0.2, and the stop button SB2 is connected to the input terminal (13-2) I0.3; The two pressure switches are: a left pressure switch (12) and a right pressure switch (2), the left pressure switch (12) is connected to the input terminal (13-2) I0.0, and the right pressure switch (2) is connected to the input terminal (13-2) I0.1; The analog input and output module (13-1) comprises: 1 input signal wiring terminal and 2 output signal wiring terminals; The connection terminals 0+ and 0- of the analog input and output module (13-1) are connected to the pressure sensor (14); The first output terminal 0M and 0 of the analog input and output module (13-1) are connected to the coil of the proportional speed regulating valve (10), and the second output terminal 1M and 1 are connected to the coil of the electromagnetic proportional overflow valve (7); The electromagnetic reversing valve has two coils: a left reversing valve coil (6-1) and a right reversing valve coil (6-2), and the two coils are connected to an output terminal (13-3).

2. An intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The inlet of the proportional speed regulating valve (10) is connected to the inlet of the electromagnetic proportional relief valve (7); the outlet of the electromagnetic proportional relief valve (7) is connected to the inlets of the third one-way valve (8) and the fourth one-way valve (5); the inlet of the proportional speed regulating valve (10) is simultaneously connected to the outlets of the first one-way valve (9) and the second one-way valve (4); the outlet of the proportional speed regulating valve (10) is simultaneously connected to the outlets of the first hydraulically controlled one-way valve (11) and the second hydraulically controlled one-way valve (3); The inlet of the first hydraulically controlled one-way valve (11) is in communication with the left chamber of the hydraulic cylinder (1), and the inlet of the second hydraulically controlled one-way valve (3) is in communication with the right chamber of the hydraulic cylinder (1). The hydraulic control port of the first hydraulically controlled one-way valve (11) is in communication with the A port of the electromagnetic reversing directional valve (6), and the hydraulic control port of the second hydraulically controlled one-way valve (3) is in communication with the B port of the electromagnetic reversing directional valve (6); The inlet of the first one-way valve (9) is communicated with the A port of the electromagnetic reversing valve (6), the inlet of the second one-way valve (4) is communicated with the B port of the electromagnetic reversing valve (6), the outlet of the third one-way valve (8) is communicated with the A port of the electromagnetic reversing valve (6), the outlet of the fourth one-way valve (5) is communicated with the B port of the electromagnetic reversing valve (6), the outlet of the fifth one-way valve (16) is communicated with the A port of the electromagnetic reversing valve (6), the inlet of the fifth one-way valve (16) is communicated with the left chamber of the hydraulic cylinder (1), the outlet of the sixth one-way valve (15) is communicated with the B port of the electromagnetic reversing valve (6), and the inlet of the sixth one-way valve (15) is communicated with the right chamber of the hydraulic cylinder (1).

3. An intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The pressure sensor (14) is communicated with the inlet of the proportional speed regulating valve (10).

4. An intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The left pressure switch (12) is communicated with the left chamber of the hydraulic cylinder (1), and the right pressure switch (2) is communicated with the right chamber of the hydraulic cylinder (1).

5. The intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The P port of the electromagnetic reversing valve (6) is in communication with the pressure oil, and the T port of the electromagnetic reversing valve (6) is in communication with the oil tank.

6. The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system according to claim 1, characterized in that: The piston rod of the hydraulic cylinder (1) is extended, comprising the following steps: The control unit output terminal (13-3) outputs a control signal, the left coil (6-1) of the reversing valve is energized, the electromagnetic reversing valve is switched to the left position, and the pressure oil passes through the A port of the electromagnetic reversing valve (6), the first check valve (9), the proportional speed regulating valve (10), and the first hydraulic control check valve (11) into the left chamber of the hydraulic cylinder (1), thereby supplying oil to the hydraulic cylinder; The oil in the right chamber of the hydraulic cylinder (1) returns to the oil tank through the sixth one-way valve (15) and the B port of the electromagnetic reversing valve (6); The oil at the outlet of the electromagnetic proportional relief valve (7) returns to the oil tank through the fourth check valve (5) and the B port of the electromagnetic reversing valve (6); During the extension process of the hydraulic cylinder, the control unit outputs a first analog signal according to a preset program to control the opening size of the proportional speed regulating valve (10), thereby adjusting the extension speed of the hydraulic cylinder, and the control unit outputs a second analog signal to control the set pressure of the proportional relief valve (7), thereby adjusting the working pressure of the hydraulic cylinder; When the hydraulic cylinder extends to the end point, the oil pressure on the left side of the hydraulic cylinder increases, triggering the left pressure switch (12) to generate a signal. The signal enters the control unit through the input terminal (13-2). The control unit generates a control signal, which is output to the right coil (6-2) of the reversing valve through the output terminal (13-3). The reversing valve changes to the right position, and the hydraulic oil flows out from the B port of the electromagnetic reversing valve (6) into the right side of the hydraulic cylinder, and the hydraulic cylinder retracts.

7. The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system according to claim 1, characterized in that: The piston rod of the hydraulic cylinder (1) is retracted, comprising the following steps: The control unit output terminal (13-3) outputs a control signal, the right coil (6-2) of the reversing valve is energized, the electromagnetic reversing valve is switched to the right position, and the pressure oil passes through the B port of the electromagnetic reversing valve (6), the second check valve (4), the proportional speed regulating valve (10), and the second hydraulic control check valve (3) into the right chamber of the hydraulic cylinder (1), thereby supplying oil to the hydraulic cylinder; The oil in the left chamber of the hydraulic cylinder (1) returns to the oil tank through the fifth one-way valve (16) and the A port of the electromagnetic reversing valve (6); The oil at the outlet of the electromagnetic proportional relief valve (7) returns to the oil tank through the third non-return valve (8) and the A port of the electromagnetic reversing valve (6); During the retraction process of the hydraulic cylinder, according to a preset program, the control unit outputs a first analog signal to control the opening size of the proportional speed regulating valve (10), thereby adjusting the retraction speed of the hydraulic cylinder (1), and the control unit outputs a second analog signal to control the set pressure of the proportional relief valve, thereby adjusting the working pressure of the hydraulic cylinder (1); When the hydraulic cylinder retracts to the end point, the pressure on the right side of the hydraulic cylinder (1) increases, triggering the right side pressure switch (2). The right side pressure switch generates a signal, which enters the control unit through the input terminal (13-2). The control unit generates a control signal, which is output to the left coil (6-1) of the reversing valve through the output terminal (13-3). The reversing valve switches to the left position, and the hydraulic oil flows out from the port A of the reversing valve (6) and enters the left side of the hydraulic cylinder (1), and the hydraulic cylinder extends.

8. The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The left pressure switch (12), the right pressure switch (2), the electromagnetic reversing valve (6), and the control unit (13) realize automatic reciprocating operation, including the following steps: When the start button SB1 is pressed, the control unit (13) sends a signal, the left coil (6-1) of the reversing valve is energized, the electromagnetic reversing valve (6) changes to the left position, the hydraulic cylinder (1) extends, the hydraulic cylinder moves to the end point, the left pressure switch (12) sends a signal, the control unit (13) controls the right coil (6-2) of the reversing valve to be energized, the hydraulic cylinder (1) retracts, and continues to move to the end point, the right pressure switch (2) sends a signal, the control unit (13) controls the left coil (6-1) of the reversing valve to be energized, and the hydraulic cylinder extends again, and this process is repeated to achieve automatic reciprocating operation.

9. The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system as claimed in claim 1, characterized in that: The proportional speed regulating valve (10), the electromagnetic proportional overflow valve (7), and the control unit (13) realize bidirectional speed regulation and pressure regulation. The control method comprises the following steps: When the hydraulic cylinder is extended or retracted, the control unit (13) outputs two control signals respectively to control the proportional speed regulating valve (10) and the electromagnetic proportional relief valve (7), adjust the opening size of the proportional speed regulating valve (10), and adjust the set pressure of the electromagnetic proportional relief valve (7), thereby realizing speed control and pressure control in both the extension and retraction directions of the hydraulic cylinder (1).

10. The control method of the intelligent bidirectional speed regulating hydraulic cylinder control system according to claim 1, characterized in that: The pressure sensor (14), the proportional speed regulating valve (10), the electromagnetic proportional overflow valve (7), and the control unit (13) automatically adjust the operating speed and the working pressure according to the fluctuation of the load. The control method comprises the following steps: After the hydraulic cylinder reaches the top, the working pressure increases to the set value of the pressure switch, the control unit (13) controls the electromagnetic reversing valve (6) to change direction, and the control unit (13) starts to count the running time and compare it with the standard running time; If the running time is less than the standard time, the working pressure is further compared with the set pressure of the proportional relief valve (7). If the two are equal, the opening of the proportional speed regulating valve (10) is reduced by Δx and the data is stored, thereby slowing down the running speed. If the former is less than the latter, the working pressure of the electromagnetic proportional relief valve (7) is reduced by ΔP and the data is stored, thereby lowering the working pressure. If the running time is greater than the standard time, further check whether the working pressure has a sudden change. If there is a sudden change, the working pressure of the electromagnetic proportional relief valve (7) increases by ΔP and stores the data, and the working pressure is increased. If there is no sudden change, further compare the working pressure with the set pressure of the proportional relief valve (10). If the two are equal, the opening of the proportional speed regulating valve (10) increases by Δx and stores the data to speed up the running speed. If the former is greater than the latter, the working pressure of the electromagnetic proportional relief valve (7) increases by ΔP and stores the data, and the working pressure is increased. After the working pressure of the electromagnetic proportional relief valve (7) is increased, it is necessary to compare the working pressure with the set pressure of the proportional relief valve (7) again. If the two are equal, the hydraulic cylinder starts to operate normally. If the former is greater than the latter, the hydraulic cylinder does not move and it is necessary to enter the next cycle process to continue to increase the working pressure of the proportional relief valve (7).

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