An electro-hydraulic control system capable of continuous large flow and stable pressure increase and a control method thereof

Abstract

The present invention relates to an electro-hydraulic control system capable of continuous and stable high-flow boosting and a control method thereof. The system comprises a motor, a hydraulic pump, a one-way valve, a proportional reversing valve, a two-position two-way electromagnetic reversing valve, and a main loading cylinder. The proportional reversing valve comprises a first proportional reversing valve and a second proportional reversing valve, the one-way valve comprises a first one-way valve and a second one-way valve, and the two-position two-way electromagnetic reversing valve comprises a first two-position two-way electromagnetic valve and a second two-position two-way electromagnetic valve. The electro-hydraulic control system capable of continuous and stable high-flow boosting and a control method thereof according to the present invention realizes the function of continuous and stable boosting through a centrally arranged boosting cylinder and switching of the electromagnetic valve based on pressure judgment, and can realize continuous and stable high-flow boosting without using a high-pressure pump source. The pressure values ​​of the pump outlet pipeline and the valve block are relatively small, thereby reducing safety risks.

Description

Technical Field

[0001] The present invention relates to the field of electro-hydraulic control systems, in particular to an electro-hydraulic control system capable of continuously increasing pressure at a large flow rate and stably and a control method thereof. Background Art

[0002] Hydraulic presses are widely used in the forming and processing of parts made of metals, ceramics and other materials. At present, as the competition of hydraulic presses becomes increasingly fierce, it is an important technical requirement to reduce costs as much as possible while meeting performance requirements. At present, increasing the pressure of the main oil cylinder is the most direct and effective way to reduce the weight of the hydraulic press. There are three main methods to increase the pressure of the main oil cylinder: first, using a high-pressure oil pump to provide high-pressure oil to the main cylinder. Not only does the oil pump need to use ultra-high pressure, but the pipeline also needs to use ultra-high pressure. The cost of hydraulic components and pipelines is very high; second, using a booster cylinder for boosting, which is divided into fixed boosting and reciprocating boosting. Among them, the fixed boosting structure is simple, but the boosting stroke is short, and it is difficult to continuously boost with a large flow rate. The reciprocating boosting that uses a switch valve for switching has pressure fluctuations or pauses, which seriously affects the product forming quality of the press; third, using motor parallel boosting, the advantage is that continuous boosting can be achieved, but the cost of large-flow motors is very high.

[0003] Therefore, the existing boosting system has the problems of high cost, short stroke or difficulty in continuous boosting. Therefore, it is urgent to propose a new low-cost continuous large-flow boosting electro-hydraulic control system and control method thereof. Summary of the invention

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an electro-hydraulic control system capable of continuous large flow and smooth pressure increase, the system comprising a motor, a hydraulic pump, a fifth one-way valve, a proportional reversing valve, a two-position two-way solenoid reversing valve, and a main loading cylinder, the proportional reversing valve comprising a first proportional reversing valve and a second proportional reversing valve, the two-position two-way solenoid reversing valve being composed of a first two-position two-way solenoid valve and a second two-position two-way solenoid valve, the left side of the hydraulic pump being connected to a motor, a relief valve being connected to one side of the lower end of the fifth one-way valve, the first proportional reversing valve and the first two-position two-way solenoid valve being energized, the hydraulic oil output by the hydraulic pump passing through the one-way valve, the first proportional reversing valve, and the second proportional reversing valve. The reversing valve flows to the first single-rod hydraulic cylinder, which extends forward. On the one hand, it pushes the second single-rod hydraulic cylinder to retract backward through the spring, and on the other hand, it pushes the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder to flow to the rodless chamber of the main loading cylinder through the third one-way valve and the first two-position two-way solenoid valve. At this time, the rodless chamber pressure of the second single-rod hydraulic cylinder gradually increases, and gradually changes from retraction movement to extension movement, the spring is compressed, and at this time, the rod chamber pressure of the second single-rod hydraulic cylinder gradually increases. The lower ends of the third one-way valve and the fourth one-way valve are respectively connected to the first pressure sensor and the second pressure sensor, and the second two-position two-way solenoid valve is connected in series with the fourth one-way valve.

[0005] Preferably, the inlet and outlet oil ports A and B at both ends of the first single-rod hydraulic cylinder and the second single-rod hydraulic cylinder can pass pressurized oil or return oil to achieve bidirectional movement.

[0006] Preferably, the hydraulic pump can be a fixed displacement pump or a variable displacement pump. The variable displacement pump can adjust the flow output according to the loading speed.

[0007] Preferably, the first proportional reversing valve, the second proportional reversing valve, the first check valve, the second check valve, the first single-rod hydraulic cylinder, the second single-rod hydraulic cylinder, the third check valve, the fourth check valve, the first two-position two-way solenoid valve and the second two-position two-way solenoid valve, the spring, the first pressure sensor and the second pressure sensor are regarded as a group of boosting units, and one group of boosting units or multiple groups of boosting units are used according to the system flow requirements.

[0008] Preferably, the diameters of the first two-position two-way solenoid valve and the second two-position two-way solenoid valve generally do not exceed 25 mm.

[0009] An electro-hydraulic control method capable of continuous large flow rate and smooth pressure increase, the method is used in an electro-hydraulic control system, and the electro-hydraulic control method capable of continuous large flow rate and smooth pressure increase comprises the following steps:

[0010] Step 1: The first proportional reversing valve and the first two-position two-way solenoid valve are energized, and the hydraulic oil output by the hydraulic pump flows to the first single-rod hydraulic cylinder through the fifth one-way valve and the first proportional reversing valve. The first single-rod hydraulic cylinder extends forward, and on the one hand, the second single-rod hydraulic cylinder is pushed backward by the spring, and on the other hand, the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder is pushed to flow to the rodless chamber of the main loading cylinder through the third one-way valve and the first two-position two-way solenoid valve;

[0011] Step 2: When the first displacement sensor detects that the piston rod of the first single-rod hydraulic cylinder reaches a certain position close to the end, the second proportional reversing valve is energized, and a part of the hydraulic oil output by the hydraulic pump continues to flow to the first single-rod hydraulic cylinder, and the other part flows through the rodless chamber of the second single-rod hydraulic cylinder through the second proportional reversing valve. At this time, the pressure of the rodless chamber of the second single-rod hydraulic cylinder gradually increases, and gradually changes from retracting motion to extending motion, the spring is compressed, and the pressure of the rod chamber of the second single-rod hydraulic cylinder gradually increases;

[0012] Step 3: When the second pressure sensor detects that its pressure value is equal to the pressure value of the pressure sensor, the first two-position two-way solenoid valve is closed and the second two-position two-way solenoid valve is opened, and the first proportional reversing valve is slowly closed, so that the two chambers of the first single-rod hydraulic cylinder lose pressure and begin to retract, so that the second single-rod hydraulic cylinder takes over the first single-rod hydraulic cylinder to achieve the effect of continuous pressurization;

[0013] Step 4: When the second displacement sensor detects that the second single-rod hydraulic cylinder reaches a certain position close to the end, the first proportional reversing valve is energized, and a part of the hydraulic oil output by the hydraulic pump continues to flow to the second single-rod hydraulic cylinder, and the other part flows through the rodless chamber of the first single-rod hydraulic cylinder through the first proportional reversing valve. At this time, the pressure of the rodless chamber of the first single-rod hydraulic cylinder gradually increases, and gradually changes from retracting motion to extending motion, the spring is compressed, and the pressure of the rod chamber of the second single-rod hydraulic cylinder gradually increases;

[0014] Step 5. When the second pressure sensor detects that its pressure value is equal to the pressure value of the first pressure sensor, the second two-position two-way solenoid valve is closed and the first two-position two-way solenoid valve is opened, and the second proportional reversing valve is slowly closed, so that the two chambers of the second single-rod hydraulic cylinder lose pressure and begin to retract, thereby achieving the effect of continuous pressurization by the first single-rod hydraulic cylinder taking over from the second single-rod hydraulic cylinder, and thus repeating the cycle to achieve the function of continuous large-flow pressurization.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] In the present invention, 1. continuous large-flow boosting can be achieved without the use of a high-pressure pump source, and the pressure values ​​of the pump outlet pipeline and the valve block are relatively small, thereby reducing safety risks; 2. By switching the solenoid valve combination based on actual pressure, the operating stability can be improved and the switching shock can be reduced; 3. A low-cost linear hydraulic cylinder is used to achieve the linked boosting function, thereby avoiding the high cost problem caused by a high-pressure pump source or a boosting motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an electro-hydraulic control system capable of continuous large flow rate and stable pressure increase and a control method thereof of the present invention;

[0018] In the accompanying drawings: 1, motor; 2, hydraulic pump; 3-1, first proportional reversing valve; 3-2, second proportional reversing valve; 4-1, first non-return valve; 4-2, second non-return valve; 5-1, first single-rod hydraulic cylinder; 5-2, second single-rod hydraulic cylinder; 6-1, third non-return valve; 6-2, fourth non-return valve; 7-1, first two-position two-way solenoid valve; 7-2, second two-position two-way solenoid valve; 8, main loading cylinder; 9, spring; 10-1, first pressure sensor; 10-2, second pressure sensor; 11-1, first displacement sensor; 11-2, second displacement sensor; 12-fifth non-return valve; 13-overflow valve. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 The present invention provides a technical solution: an electro-hydraulic control system capable of continuous large flow and smooth pressure increase, the system comprising a motor 1, a hydraulic pump 2, a fifth one-way valve 12, a proportional reversing valve, a two-position two-way solenoid reversing valve, and a main loading cylinder 8, the proportional reversing valve comprising a first proportional reversing valve 3-1 and a second proportional reversing valve 3-2, the two-position two-way solenoid reversing valve comprising a first two-position two-way solenoid valve 7-1 and a second two-position two-way solenoid valve 7-2, the left side of the hydraulic pump 2 is connected to the motor 1, the lower end side of the fifth one-way valve 12 is connected to an overflow valve 13, the first proportional reversing valve 3-1 and the first two-position two-way solenoid valve 7-1 are energized, the hydraulic oil output by the hydraulic pump 2 passes through the fifth one-way valve 12 and the first proportional reversing valve 3-1, and flows to the first one-way valve 1 The rod hydraulic cylinder 5-1, the first single-rod hydraulic cylinder 5-1 extends forward, on the one hand, it pushes the second single-rod hydraulic cylinder 5-2 to retract backward through the spring 9, and on the other hand, it pushes the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder 5-1 to flow to the rodless chamber of the main loading cylinder 8 through the third one-way valve 6-1 and the first two-position two-way solenoid valve 7-1. At this time, the rodless chamber pressure of the second single-rod hydraulic cylinder 5-2 gradually increases, and gradually changes from retraction movement to extension movement, the spring 9 is compressed, at this time, the rod chamber pressure of the second single-rod hydraulic cylinder 5-2 gradually increases, the lower ends of the third one-way valve 6-1 and the fourth one-way valve 6-2 are respectively connected to the first pressure sensor 10-1 and the second pressure sensor 10-2, and the second two-position two-way solenoid valve 7-2 is connected in series with the fourth one-way valve 6-2.

[0021] The inlet and outlet oil ports A and B at both ends of the first single-rod hydraulic cylinder 5-1 and the second single-rod hydraulic cylinder 5-2 can pass pressurized oil or return oil to achieve bidirectional movement.

[0022] The hydraulic pump 2 can be a fixed displacement pump or a variable displacement pump. The variable displacement pump can adjust the flow output according to the loading speed.

[0023] Among them, the first proportional reversing valve 3-1, the second proportional reversing valve 3-2, the first one-way valve 4-1, the second one-way valve 4-2, the first single-rod hydraulic cylinder 5-1, the second single-rod hydraulic cylinder 5-2, the third one-way valve 6-1, the fourth one-way valve 6-2, the first two-position two-way solenoid valve 7-1 and the second two-position two-way solenoid valve 7-2, the spring 9, the first pressure sensor 10-1 and the second pressure sensor 10-2 are regarded as a group of boosting units. According to the system flow requirements, one group of boosting units or multiple groups of boosting units are used.

[0024] The diameters of the first two-position two-way solenoid valve 7-1 and the second two-position two-way solenoid valve 7-2 are generally no more than 25 mm.

[0025] An electro-hydraulic control method capable of continuous large flow rate and smooth pressure increase, the method is used in an electro-hydraulic control system, and the electro-hydraulic control method capable of continuous large flow rate and smooth pressure increase comprises the following steps:

[0026] Step 1, the first proportional reversing valve 3-1 and the first two-position two-way solenoid valve 7-1 are energized, and the hydraulic oil output by the hydraulic pump 2 flows to the first single-rod hydraulic cylinder 5-1 through the fifth one-way valve 12 and the first proportional reversing valve 3-1. The first single-rod hydraulic cylinder 5-1 extends forward, and on the one hand, the second single-rod hydraulic cylinder 5-2 is pushed backward by the spring 9, and on the other hand, the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder 5-1 is pushed to flow to the rodless chamber of the main loading cylinder 8 through the third one-way valve 6-1 and the first two-position two-way solenoid valve 7-1;

[0027] Step 2: When the first displacement sensor 11-1 detects that the piston rod of the first single-rod hydraulic cylinder 5-1 reaches a certain position close to the end, the second proportional reversing valve 3-2 is energized, and a part of the hydraulic oil output by the hydraulic pump 2 continues to flow to the first single-rod hydraulic cylinder 5-1, and the other part flows through the rodless chamber of the second single-rod hydraulic cylinder 5-2 through the second proportional reversing valve 3-2. At this time, the pressure of the rodless chamber of the second single-rod hydraulic cylinder 5-2 gradually increases, and gradually changes from retracting motion to extending motion, and the spring 9 is compressed. At this time, the pressure of the rod chamber of the second single-rod hydraulic cylinder 5-2 gradually increases;

[0028] Step 3: When the second pressure sensor 10-2 detects that its pressure value is equal to the pressure value of the pressure sensor, the first two-position two-way solenoid valve 7-1 is closed and the second two-position two-way solenoid valve 7-2 is opened, and the first proportional reversing valve 3-1 is slowly closed, so that the two chambers of the first single-rod hydraulic cylinder 5-1 lose pressure and begin to retract, so that the second single-rod hydraulic cylinder 5-2 takes over from the first single-rod hydraulic cylinder 5-1 to achieve the effect of continuous pressurization;

[0029] Step 4: When the second displacement sensor 11-2 detects that the second single-rod hydraulic cylinder 5-2 reaches a certain position close to the end, the first proportional reversing valve 3-1 is energized, and a part of the hydraulic oil output by the hydraulic pump 2 continues to flow to the second single-rod hydraulic cylinder 5-2, and the other part flows through the rodless chamber of the first single-rod hydraulic cylinder 5-1 through the first proportional reversing valve 3-1. At this time, the pressure of the rodless chamber of the first single-rod hydraulic cylinder 5-1 gradually increases, and gradually changes from retracting motion to extending motion, and the spring 9 is compressed. At this time, the pressure of the rod chamber of the second single-rod hydraulic cylinder 5-2 gradually increases;

[0030] Step 5. When the second pressure sensor 10-2 detects that its pressure value is equal to the pressure value of the first pressure sensor 10-1, the second two-position two-way solenoid valve 7-2 is closed and the first two-position two-way solenoid valve 7-1 is opened, and the second proportional reversing valve 3-2 is slowly closed, so that the two chambers of the second single-rod hydraulic cylinder 5-2 lose pressure and begin to retract, so that the first single-rod hydraulic cylinder 5-1 takes over from the second single-rod hydraulic cylinder 5-2 to achieve the effect of continuous pressurization, and this cycle is repeated to achieve the function of continuous large-flow pressurization.

[0031] The present invention is an electro-hydraulic control system which can continuously and stably increase pressure with a large flow rate, comprising a motor, a variable pump, a one-way valve, a throttle valve, a two-position four-way proportional reversing valve, a two-position two-way electromagnetic reversing valve, a boosting oil cylinder, a one-way valve, a main loading cylinder, etc.

[0032] First, the first proportional reversing valve 3-1 and the first two-position two-way solenoid valve 7-1 are energized, and the hydraulic oil output by the hydraulic pump 2 first passes through the fifth one-way valve 12, the proportional reversing valve, and the two-position four-way solenoid reversing valve, and flows to the first single-rod hydraulic cylinder 5-1. The first single-rod hydraulic cylinder 5-1 extends forward, and on the one hand, it pushes the second single-rod hydraulic cylinder 5-2 to retract backward through the spring 9, and on the other hand, it pushes the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder 5-1 to flow to the rodless chamber of the main loading cylinder 8 through the third one-way valve 6-1 and the first two-position two-way solenoid valve 7-1, and the function of the first one-way valve 4-1 is to prevent the hydraulic oil from flowing back to the oil tank. Since the areas of the rod chamber and the rodless chamber of the first single-rod hydraulic cylinder 5-1 are not equal and are in a certain proportional relationship, the pump output oil will be pressurized approximately according to the proportional relationship and then output to the rod chamber of the main loading cylinder 8; when the first displacement sensor 11-1 detects that the piston rod of the first single-rod hydraulic cylinder 5-1 reaches a position close to the end, the second proportional reversing valve 3-2 is energized, and a part of the hydraulic oil output by the hydraulic pump 2 continues to flow to the first single-rod hydraulic cylinder 5-1, and the other part flows through the second proportional reversing valve 3-2 through the rod chamber of the second single-rod hydraulic cylinder 5-2 The pressure in the rodless cavity of the second single-rod hydraulic cylinder 5-2 gradually increases, and the retracting motion gradually changes to the extending motion. The spring 9 is compressed. At this time, the pressure in the rod cavity of the second single-rod hydraulic cylinder 5-2 gradually increases. When the second pressure sensor 10-2 detects that its pressure value is equal to the pressure value of the pressure sensor, the first two-position two-way solenoid valve 7-1 is closed and the second two-position two-way solenoid valve 7-2 is opened, and the first proportional reversing valve 3-1 is slowly closed, so that the two cavities of the first single-rod hydraulic cylinder 5-1 lose pressure and begin to retract, realizing the second single-rod hydraulic cylinder 5-1. 5-2 takes over from the first single-rod hydraulic cylinder 5-1 to achieve the effect of continuous pressurization; when the second displacement sensor 11-2 detects that the second single-rod hydraulic cylinder 5-2 has reached a position close to the end, the first proportional reversing valve 3-1 is energized, and a part of the hydraulic oil output by the hydraulic pump 2 continues to flow to the second single-rod hydraulic cylinder 5-2, and the other part flows through the first proportional reversing valve 3-1 through the rod chamber of the first single-rod hydraulic cylinder 5-1. At this time, the pressure in the rodless chamber of the first single-rod hydraulic cylinder 5-1 gradually increases, and gradually changes from retracting motion to extending motion, and the spring 9 is Compression, at this time, the rod chamber pressure of the second single-rod hydraulic cylinder 5-2 gradually increases; when the second pressure sensor 10-2 detects that its pressure value is equal to the pressure value of the pressure sensor, the second two-position two-way solenoid valve 7-2 is closed and the first two-position two-way solenoid valve 7-1 is opened, and the second proportional reversing valve 3-2 is slowly closed, so that the two chambers of the second single-rod hydraulic cylinder 5-2 lose pressure and begin to retract, achieving the effect of continuous pressurization by the first single-rod hydraulic cylinder 5-1 replacing the second single-rod hydraulic cylinder 5-2, thereby repeating the cycle to achieve the function of continuous large-flow pressurization.

[0033] It should also be noted that the implementation of this system is not limited to the above schematic diagram. In order to achieve corresponding application functions in different occasions, the system may also have the following changes:

[0034] The hydraulic pump 2 can be a fixed displacement pump or a variable displacement pump. The advantage of using a variable displacement pump is that the flow output can be adjusted according to the loading speed, thereby achieving the purpose of high efficiency and energy saving;

[0035] According to the system flow requirements, one group of motor pumps can be used, or multiple groups of motor pumps can be used; the first proportional reversing valve 3-1, the second proportional reversing valve 3-2, the first non-return valve 4-1, the second non-return valve 4-2, the first single-rod hydraulic cylinder 5-1, the second single-rod hydraulic cylinder 5-2, the third non-return valve 6-1, the fourth non-return valve 6-2, the first two-position two-way solenoid valve 7-1, the second two-position two-way solenoid valve 7-2, the spring 9, the first pressure sensor 10-1, and the second pressure sensor 10-2 are regarded as a group of boosting units. According to the system flow requirements, one group of boosting units can be used, or multiple groups of boosting units can be used; for the first single-rod hydraulic cylinder 5-1 and the second single-rod hydraulic cylinder 5-2, different ratios of the area of ​​the rod chamber to the rodless chamber can be designed according to the required boost ratio.

[0036] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An electro-hydraulic control system capable of continuous large flow rate and stable pressure increase, the system comprising a motor (1), a hydraulic pump (2), a fifth non-return valve (12), a proportional reversing valve, a two-position two-way electromagnetic reversing valve, and a main loading cylinder (8), characterized in that: The proportional reversing valve comprises a first proportional reversing valve (3-1) and a second proportional reversing valve (3-2); the two-position two-way solenoid reversing valve comprises a first two-position two-way solenoid valve (7-1) and a second two-position two-way solenoid valve (7-2); the left side of the hydraulic pump (2) is connected to a motor (1); a lower end side of the fifth one-way valve (12) is connected to a relief valve (13); the first proportional reversing valve (3-1) and the first two-position two-way solenoid valve (7-1) are energized, and the hydraulic oil output by the hydraulic pump (2) passes through the first two-position two-way solenoid valve (7-1). The first one-way valve (12) and the first proportional reversing valve (3-1) flow to the first single-rod hydraulic cylinder (5-1), and the first single-rod hydraulic cylinder (5-1) extends forward. On the one hand, the second single-rod hydraulic cylinder (5-2) is pushed backward by the spring (9), and on the other hand, the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder (5-1) is pushed to flow to the rodless chamber of the main loading cylinder (8) through the third one-way valve (6-1) and the first two-position two-way solenoid valve (7-1). The second proportional reversing valve (3-2) is energized, and the hydraulic pump (2) outputs the hydraulic oil. Part of the hydraulic oil continues to flow to the first single-rod hydraulic cylinder (5-1), and the other part flows through the rodless chamber of the second single-rod hydraulic cylinder (5-2) through the second proportional reversing valve (3-2). At this time, the pressure in the rodless chamber of the second single-rod hydraulic cylinder (5-2) gradually increases, and the retracting movement gradually changes to the extending movement. The spring (9) is compressed. At this time, the pressure in the rod chamber of the second single-rod hydraulic cylinder (5-2) gradually increases, closing the first two-position two-way solenoid valve (7-1) and opening the second two-position two-way solenoid valve (7-2). The hydraulic oil in the rod chamber of the second single-rod hydraulic cylinder (5-2) flows to the rodless chamber of the main loading cylinder (8) through the fourth one-way valve (6-2) and the second two-position two-way solenoid valve (7-2); the lower ends of the third one-way valve (6-1) and the fourth one-way valve (6-2) are respectively connected to the first pressure sensor (10-1) and the second pressure sensor (10-2); the upper end of the first proportional reversing valve (3-1) is connected to the first one-way valve (4-1); and the upper end of the second proportional reversing valve (3-2) is connected to the second one-way valve (4-2).

2. The electro-hydraulic control system capable of continuous large flow rate and stable pressure increase according to claim 1, characterized in that: The inlet and outlet oil ports A and B at both ends of the first single-rod hydraulic cylinder (5-1) and the second single-rod hydraulic cylinder (5-2) can both pass pressure oil or return oil to achieve bidirectional movement.

3. The electro-hydraulic control system capable of continuous large flow rate and stable pressure increase according to claim 1, characterized in that: The hydraulic pump (2) may be a fixed displacement pump or a variable displacement pump. The variable displacement pump may be used to adjust the flow output according to the loading speed.

4. The electro-hydraulic control system capable of continuous large flow rate and stable pressure increase according to claim 1, characterized in that: The first proportional reversing valve (3-1), the second proportional reversing valve (3-2), the first non-return valve (4-1), the second non-return valve (4-2), the first single-rod hydraulic cylinder (5-1), the second single-rod hydraulic cylinder (5-2), the third non-return valve (6-1), the fourth non-return valve (6-2), the first two-position two-way solenoid valve (7-1), the second two-position two-way solenoid valve (7-2), the spring (9), the first pressure sensor (10-1), and the second pressure sensor (10-2) are regarded as a group of boosting units. According to the flow demand of the system, one group of boosting units or multiple groups of boosting units are used.

5. The electro-hydraulic control system capable of continuous large flow rate and stable pressure increase according to claim 1, characterized in that: The diameters of the first two-position two-way solenoid valve (7-1) and the second two-position two-way solenoid valve (7-2) generally do not exceed 25 mm.

6. An electro-hydraulic control method capable of continuous large flow rate and stable pressure increase, the method is used in an electro-hydraulic control system, characterized in that: The electro-hydraulic control method capable of continuous large flow and smooth pressure increase comprises the following steps: Step 1: The first proportional reversing valve (3-1) and the first two-position two-way solenoid valve (7-1) are energized, and the hydraulic oil output by the hydraulic pump (2) flows through the fifth one-way valve (12) and the first proportional reversing valve (3-1) to the first single-rod hydraulic cylinder (5-1). The first single-rod hydraulic cylinder (5-1) extends forward, and on the one hand, the second single-rod hydraulic cylinder (5-2) is pushed backward by the spring (9), and on the other hand, the hydraulic oil in the rod chamber of the first single-rod hydraulic cylinder (5-1) is pushed to flow to the rodless chamber of the main loading cylinder (8) through the third one-way valve (6-1) and the first two-position two-way solenoid valve (7-1); Step 2: When the first displacement sensor (11-1) detects that the piston rod of the first single-rod hydraulic cylinder (5-1) reaches a certain position close to the end, the second proportional reversing valve (3-2) is energized, and a portion of the hydraulic oil output by the hydraulic pump (2) continues to flow to the first single-rod hydraulic cylinder (5-1), and the other portion flows through the rodless chamber of the second single-rod hydraulic cylinder (5-2) through the second proportional reversing valve (3-2). At this time, the pressure in the rodless chamber of the second single-rod hydraulic cylinder (5-2) gradually increases, and gradually changes from a retracting motion to an extending motion. The spring (9) is compressed, and at this time, the pressure in the rod chamber of the second single-rod hydraulic cylinder (5-2) gradually increases; Step 3: When the second pressure sensor (10-2) detects that its pressure value is equal to the pressure value of the first pressure sensor (10-1), the first two-position two-way solenoid valve (7-1) is closed and the second two-position two-way solenoid valve (7-2) is opened, and the first proportional reversing valve (3-1) is slowly closed, so that the two chambers of the first single-rod hydraulic cylinder (5-1) lose pressure and begin to retract, so that the second single-rod hydraulic cylinder (5-2) takes over from the first single-rod hydraulic cylinder (5-1) to achieve a continuous pressurization effect; Step 4: When the second displacement sensor (11-2) detects that the second single-rod hydraulic cylinder (5-2) reaches a certain position close to the end, the first proportional reversing valve (3-1) is energized, and a portion of the hydraulic oil output by the hydraulic pump (2) continues to flow to the second single-rod hydraulic cylinder (5-2), and the other portion flows through the first proportional reversing valve (3-1) through the rodless chamber of the first single-rod hydraulic cylinder (5-1). At this time, the pressure in the rodless chamber of the first single-rod hydraulic cylinder (5-1) gradually increases, and gradually changes from a retracting motion to an extending motion. The spring (9) is compressed, and at this time, the pressure in the rod chamber of the first single-rod hydraulic cylinder (5-1) gradually increases; Step 5: When the first pressure sensor (10-1) detects that its pressure value is equal to the pressure value of the second pressure sensor (10-2), the second two-position two-way solenoid valve (7-2) is closed and the first two-position two-way solenoid valve (7-1) is opened, and the second proportional reversing valve (3-2) is slowly closed, so that the two chambers of the second single-rod hydraulic cylinder (5-2) lose pressure and begin to retract, so that the first single-rod hydraulic cylinder (5-1) takes over from the second single-rod hydraulic cylinder (5-2) to achieve the effect of continuous pressurization, and thus the cycle is repeated to achieve the function of continuous large-flow pressurization.

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