An integrated cartridge multi-way valve for pipe jacking machines

Abstract

This invention belongs to the field of fluid transmission control and relates to an integrated cartridge-type multi-way valve specifically for pipe jacking machines. It includes a safety control valve assembly, a machine head rotation control valve assembly, a main jacking advance / retreat control valve assembly, a pressurization and flow merging direction control valve assembly, a machine head and main jacking pressurization and flow merging valve assembly, and a correction / relay control valve assembly. Each assembly has approximately the same dimensions and uses cartridge valves to control direction and flow. The cartridge valves employ valve core feedback closed-loop control to improve control accuracy. The pilot oil route for the cartridge valves is provided by a small-diameter three-position four-way directional valve. All assemblies are connected together by sealing rings and long bolts. This invention, by highly integrating the functions of various execution parts of the pipe jacking machine and using cartridge valves as the main valve core control, solves the problems of pipeline accumulation and low control accuracy in the pump station of pipe jacking machines. This significantly improves the construction efficiency of the pipe jacking machine, reduces power loss, makes operation more convenient, and is more suitable for construction in various geological formations.

Description

Technical Field

[0001] This invention belongs to the field of fluid transmission control and relates to an integrated cartridge-type multi-way valve for pipe jacking machines. Background Technology

[0002] Most pipe jacking machines currently use plate-type integrated valves to connect to hydraulic pipelines. These machines use a lot of joints and hoses, which results in significant friction loss and localized loss in the hydraulic pipelines. Furthermore, they are difficult to repair when hydraulic failures occur, and pipeline accumulation is quite serious, occupying a large space and generating significant impact, vibration, and noise.

[0003] A significant portion of the time during pipe jacking machine operation involves medium- to long-distance hydraulic transmission. Currently, the domestically produced electro-proportional control directional valve suffers from overly sensitive current control. During operation, due to steady-state (transient) hydraulic forces and the hysteresis effect of the electromagnet, the current magnitude and valve core opening are not linearly proportional. This results in a large hysteresis in the control transmission of the electro-proportional control valve, which is a significant problem when the pipe jacking machine jacks over long distances. Signal transmission delays and difficulty in accurately controlling the valve core opening lead to difficulties in maintaining linear and stable output flow, resulting in a poor user experience.

[0004] Currently, almost all operations of pipe jacking machines are controlled via a control panel. The panel has many control buttons and monitoring screens, requiring operators to constantly monitor the screens and control panels. A slight lapse in attention can lead to misalignment or blockage of the jacking machine. Therefore, customers urgently need a hydraulic system that is easy to operate and has high control precision to free up manpower.

[0005] Based on this, a new integrated multi-way valve was developed, which integrates head rotation, main jack propulsion, deviation correction extension and retraction, and mud opening and closing. It has a large flow capacity, sensitive valve core action, precise position control, strong anti-clogging ability, good sealing performance, low leakage loss, and complete functions. It reduces the amount of hydraulic pipelines and joints used, greatly simplifies the hydraulic system, and is more conducive to standardization and troubleshooting. Summary of the Invention

[0006] To overcome the above problems, this invention provides an integrated cartridge-type multi-way valve for pipe jacking machines, which consists of six sections. The first section serves as the safety and pilot signal input control valve for the entire valve block, while the remaining five sections each control their respective actuators. Each section of the multi-way valve integrates a directional control valve, a flow control valve, a safety valve, a pressure compensation valve, and a check valve into one unit. The sections are connected in parallel and with long bolts to ensure sealing. This multi-way valve can achieve speed regulation of the machine head rotation, speed regulation of the main jacking flow, remote control of mid-position unloading, and pilot overflow control, ensuring that the valve is suitable for small and medium-sized hydraulically driven pipe jacking machines.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] An integrated cartridge-type multi-way valve for a pipe jacking machine consists of six valves I, II, III, IV, V, and VI connected in parallel. Among them, valve I is a safety control valve, valve II is a machine head rotation control valve, valve III is a main jacking advance / retreat control valve, valve IV is a pressurization and flow directional control valve, valve V is a machine head main jacking pressurization and flow directional valve, and valve VI is a correction / relay control valve.

[0009] Furthermore, in the first connection, the valve's built-in filter is connected to the LS oil circuit and in series with the LS speed control valve, which is connected to the valve block's main return oil circuit T channel; the neutral position P1 push-pull pump unloading valve is connected to the rotary pump's high-pressure inlet P2 and to the return oil circuit T channel; the neutral position P2 rotary pump unloading valve is connected to the push-pull pump's high-pressure inlet P1 and to the return oil circuit T channel; the X oil circuit pressure reducing valve is connected to the P2 oil circuit and, together with the valve's built-in filter, is connected to the X oil circuit; and the LS overflow valve is connected to the LS oil circuit and the T channel.

[0010] Furthermore, in the second, third, and sixth sections, the one-way valve is connected to the LS oil circuit and is connected in series with the upstream pressure compensation valve; the upstream pressure compensation valve is connected to the rotary pump P2 oil circuit; the B-port pilot-operated cartridge relief valve is connected to the corresponding B oil circuit of each section, and the A-port pilot-operated cartridge relief valve is connected to the corresponding A oil circuit of each section; the upstream pressure compensation valve is connected to the inlet P port of the three-position four-way cartridge directional control valve, and the outlet ports of the second and third cartridge valves of the three-position four-way cartridge directional control valve are respectively connected to the corresponding A and B oil circuits of each section;

[0011] Furthermore, the second section also includes a two-position three-way directional control valve whose main oil circuit is connected to the oil outlets of the second and third cartridge valves of the three-position four-way cartridge directional control valve, respectively; the control oil circuit of the two-position three-way directional control valve is connected to the pilot oil circuit of the third cartridge valve of the three-position four-way cartridge directional control valve; and a check valve is connected to the two-position three-way directional control valve.

[0012] Furthermore, the third section also includes a two-position three-way directional control valve two whose right-position main oil circuit is connected to the oil outlet A of the second cartridge valve of the three-position four-way cartridge directional control valve, and its left-position main oil circuit is connected to the T port of the integrated cartridge multi-way valve. The pilot oil circuit of the two-position three-way directional control valve two is connected to the second and third cartridge valves of the three-position four-way cartridge directional control valve. The main oil circuit of the two-position three-way directional control valve three is connected to the second and third cartridge valves of the three-position four-way cartridge directional control valve, and its control oil circuit is connected to the pilot oil circuit of the third cartridge valve of the three-position four-way cartridge directional control valve. The check valve four is connected to the two-position three-way directional control valve three.

[0013] Furthermore, in the fourth section, the pilot-operated proportional pressure reducing valve one is connected to the external control port X, the lower position of the proportional directional control valve is connected to the pilot-operated proportional pressure reducing valve one, the upper position of the proportional directional control valve is connected to the pilot-operated proportional pressure reducing valve two, and the pilot-operated proportional pressure reducing valve two is connected to the external drain port Y.

[0014] Furthermore, in the fifth section, the variable signal controller is connected to the three-position four-way cartridge directional control valve and to the pilot-operated proportional pressure reducing valve one and the pilot-operated proportional pressure reducing valve two in the fourth section. The valve upstream pressure compensation valve three is connected to the three-position four-way cartridge directional control valve three, and the check valve five connects the valve upstream pressure compensation valve three and the LS oil circuit.

[0015] Furthermore, the A-port pilot-operated cartridge relief valve and the B-port pilot-operated cartridge relief valve have the same structure, specifically including a pilot valve, a first damping orifice, a cartridge valve, and a second damping orifice; the second damping orifice is connected to the B oil circuit, the first damping orifice is connected to the cartridge valve and the second damping orifice, and the pilot valve is connected to the first damping orifice.

[0016] Furthermore, the three-position four-way cartridge directional control valve includes a first cartridge valve, a second cartridge valve, a third cartridge valve, a fourth cartridge valve, and an electrically controlled three-position four-way solenoid directional valve; the first cartridge valve, the second cartridge valve, the third cartridge valve, and the fourth cartridge valve are connected in series, the A port of the electrically controlled three-position four-way solenoid directional valve is connected to the first cartridge valve and the third cartridge valve respectively, the B port of the electrically controlled three-position four-way solenoid directional valve is connected to the second cartridge valve and the fourth cartridge valve respectively, wherein the P port of the three-position four-way cartridge directional control valve is connected to the second cartridge valve, the third cartridge valve, and the electrically controlled three-position four-way solenoid directional valve respectively;

[0017] Among them, the three-position four-way cartridge directional control valves in the second, third and sixth links lead out two oil lines from the oil outlets of the second and third cartridge valves to port A and port B respectively to connect to the oil cylinder.

[0018] Furthermore, the cartridge valve includes a pilot proportional electromagnet, a push rod, a valve body, a cartridge valve core, a pilot valve core, a spring, a cartridge valve fixing plate, a cartridge valve main body, and a return spring;

[0019] The pilot proportional electromagnet is located at the leftmost end of the valve body, and the left end of the push rod is connected to the pilot proportional electromagnet, while the right end is connected to the pilot valve core.

[0020] The pilot valve core is installed inside the integral cartridge valve core, and springs are provided at its left and right ends;

[0021] The integral cartridge valve core is installed in the valve body, with its inner side contacting the pilot valve core and its outer side contacting the valve body.

[0022] The left side of the cartridge valve fixing plate is fixedly connected to the valve body, and a circular hole is provided in the center of the plate. A return spring is fixed on the right side of the plate.

[0023] The inner side of the cartridge valve main valve body is in contact with the integral cartridge valve core, and its outer side is threaded to the valve body. It has an oil passage hole A and an oil sealing area.

[0024] The reset spring is sleeved on the right end of the integral cartridge valve core, its left end is fixed to the right side of the cartridge valve fixing plate, and its right end is connected to the main valve body of the cartridge valve.

[0025] The multi-way valve of this invention features reduced production costs for pipe jacking machines, optimized hydraulic systems, reduced system heat generation, and improved transmission efficiency, thus more effectively meeting customer operation and usage requirements. It significantly simplifies hydraulic pipelines; hydraulic oil flows directly from the oil pump into the P port of the multi-way valve, and then directly into the actuator via the hydraulic cartridge multi-way valve. This greatly improves system stability, makes operation more convenient, and control more sensitive. Simultaneously, the cartridge valve's closed-loop self-regulating control effectively solves the problem of low control accuracy in existing electro-proportional open-loop control. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the principle of an integrated cartridge-type multi-way valve used in a pipe jacking machine;

[0027] Figure 2 This is a partially enlarged schematic diagram of the first three sections of the integrated cartridge multi-way valve used in pipe jacking machines;

[0028] Figure 3 This is a partially enlarged schematic diagram of the rear three-way integrated cartridge multi-way valve used in pipe jacking machines;

[0029] Figure 4 This is a simplified cross-sectional diagram of the cartridge valve components;

[0030] In the picture:

[0031] 1.1-Valve built-in filter one, 1.2-LS speed control valve, 1.3-P1 push-pull pump unloading valve, 1.4-P2 rotary pump unloading valve, 1.5-X oil circuit pressure reducing valve, 1.6-Electro-proportional relief valve, 1.7-Valve built-in filter two, 1.8-LS relief valve;

[0032] 2.1-Check valve one, 2.2-Pressure compensation valve one, 2.3-B1 port pilot-operated cartridge relief valve, 2.4-A1 port pilot-operated cartridge relief valve, 2.5-Three-position four-way cartridge directional control valve one, 2.6-Two-position three-way directional control valve one, 2.7-Check valve two;

[0033] 2.3.1 - First pilot valve; 2.3.2 - First damping orifice; 2.3.3 - First cartridge valve; 2.3.4 - Second damping orifice;

[0034] 2.4.1 - Second pilot valve, 2.4.2 - Third damping orifice, 2.4.3 - Second cartridge valve, 2.4.4 - Fourth damping orifice;

[0035] 2.5.1-First cartridge valve, 2.5.2-Second cartridge valve, 2.5.3-Third cartridge valve, 2.5.4-Fourth cartridge valve, 2.5.5-First electrically controlled three-position four-way solenoid directional valve;

[0036] 3.1-Check valve III; 3.2-Pressure compensation valve II; 3.3-B2 port pilot-operated cartridge relief valve; 3.4-A2 port pilot-operated cartridge relief valve; 3.5-Three-position four-way cartridge directional control valve II; 3.6-Two-position three-way directional control valve II; 3.7-Two-position three-way directional control valve III; 3.8-Check valve IV;

[0037] 3.3.1 - Third pilot valve, 3.3.2 - Fifth damping orifice, 3.3.3 - Third cartridge valve, 3.3.4 - Sixth damping orifice;

[0038] 3.4.1 - Fourth pilot valve, 3.4.2 - Seventh damping orifice, 3.4.3 - Fourth cartridge valve, 3.4.4 - Eighth damping orifice;

[0039] 3.5.1 - Fifth cartridge valve, 3.5.2 - Sixth cartridge valve, 3.5.3 - Seventh cartridge valve, 3.5.4 - Eighth cartridge valve, 3.5.5 - Second electrically controlled three-position four-way solenoid directional valve;

[0040] 4.1-Pilot-operated proportional pressure reducing valve one; 4.2-Proportional directional control valve; 4.3-Pilot-operated proportional pressure reducing valve two;

[0041] 5.1 - Variable signal controller; 5.2 - Three-position four-way cartridge directional control valve III; 5.3 - Inlet pressure compensation valve III; 5.4 - Check valve V;

[0042] 5.2.1 - Ninth cartridge valve, 5.2.2 - Tenth cartridge valve, 5.2.3 - Eleventh cartridge valve, 5.2.4 - Twelfth cartridge valve, 5.2.5 - Third electrically controlled three-position four-way solenoid directional valve;

[0043] 6.1-Check valve VI; 6.2-Pressure compensation valve IV; 6.3-B3 port pilot-operated cartridge relief valve; 6.4-A3 port pilot-operated cartridge relief valve; 6.5-Three-position four-way cartridge relief valve.

[0044] 6.3.1 - Fifth pilot valve, 6.3.2 - Ninth damping orifice, 6.3.3 - Fifth cartridge valve, 6.3.4 - Tenth damping orifice;

[0045] 6.4.1 - Sixth pilot valve, 6.4.2 - Eleventh damping orifice, 6.4.3 - Sixth cartridge valve, 6.4.4 - Twelfth damping orifice;

[0046] 6.5.1-Thirteenth cartridge valve, 6.5.2-Fourteenth cartridge valve, 6.5.3-Fifteenth cartridge valve, 6.5.4-Sixteenth cartridge valve, 6.5.5-Fourth electrically controlled three-position four-way solenoid directional valve;

[0047] P1 - High-pressure oil inlet of push-pull pump, P2 - High-pressure oil inlet of rotary pump, X1 - External control oil inlet, Y1 - External drain oil inlet, LS - Load feedback oil circuit, A1 - Oil inlet of machine head rotary motor, B1 - Oil return port of machine head rotary motor, A2 - Oil inlet of main jack advance / reverse, B2 - Oil return port of main jack advance / reverse, A3 - Oil inlet of correction / relay cylinder, B3 - Oil return port of correction / relay cylinder, T - Total return oil circuit of the entire valve block;

[0048] 7.1 Pilot proportional electromagnet, 7.2 Push rod, 7.3 Valve body, 7.4 Cartridge valve core, 7.5 Pilot valve core, 7.6 Spring, 7.7 Cartridge valve mounting plate, 7.8 Cartridge valve main body, 7.9 Cartridge valve return spring. Detailed Implementation

[0049] To make the description of this invention patent more intuitive and accurate, and the implementation scheme and principle clearer, a detailed explanation is provided below in conjunction with the accompanying drawings.

[0050] An integrated cartridge-type multi-way valve for pipe jacking machines is characterized by its high degree of integration. Each section consists of a corresponding cartridge control valve. Under the control of the proportional directional control valve, the valve opening of the cartridge valve is adjusted, thereby changing the flow rate from the cartridge valve to the actuator. Each section's cartridge valve operates unidirectionally, forming a B-type half-bridge circuit, which stabilizes the flow rate. Each section is equipped with a pressure compensation valve and a pilot-operated relief valve. Its advantages include a compact structure, high control precision by changing the flow rate to the actuator through the corresponding cartridge valve opening size, stable operating performance, extremely low leakage, and high energy efficiency and noise reduction. It is suitable for the hydraulic control systems of small and medium-sized pipe jacking machines.

[0051] like Figures 1 to 3 As shown, the integrated cartridge multi-way valve is assembled by connecting six valves I, II, III, IV, V, and VI in parallel with long bolts, and O-rings are used to seal the adjacent valves.

[0052] Section I - Safety control valve; Section II - Head rotation control valve; Section III - Main jack advance / retreat control valve; Section IV - Pressurization and flow direction control valve; Section V - Head main jack pressurization and flow control valve; Section VI - Correction / relay control valve.

[0053] This integrated cartridge-type multi-way valve adopts a combination of cartridge-type and electro-proportional control, which can compensate for the shortcomings of corresponding cartridge-type maintenance and is more conducive to the construction of pipe jacking machine. Among them, the cartridge valves and control methods used in the second, third and sixth sections are almost the same, while the fourth and fifth sections adopt a combination of electro-proportional and cartridge-type control.

[0054] In the first section, the built-in filter 1.1 is connected in series with the LS oil circuit and the LS speed control valve 1.2. The LS speed control valve 1.2 is connected to the main return oil circuit T channel of the valve block. The neutral position P1 push-pull pump unloading valve 1.3 is connected to the high-pressure oil inlet P2 of the rotary pump and the return oil circuit T channel. The neutral position P2 rotary pump unloading valve 1.4 is connected to the high-pressure oil inlet P1 of the push-pull pump and the return oil circuit T channel. The X oil circuit pressure reducing valve 1.5 is connected to the P2 oil circuit and connected to the X oil circuit via the built-in filter 1.7. The LS overflow valve 1.8 is connected to the LS oil circuit and the T channel.

[0055] In section II, check valve 2.1 is connected in series with the LS oil circuit and the upstream pressure compensation valve 2.2. The upstream pressure compensation valve 2.2 is connected to the rotary pump P2 oil circuit. Pilot-operated cartridge relief valve 2.3 at port B1 is connected to the B1 oil circuit, and pilot-operated cartridge relief valve 2.4 at port A1 is connected to the A1 oil circuit. The second damping orifice 2.3.4 is connected to the B1 oil circuit. The first damping orifice 2.3.2 is connected to the first cartridge valve 2.3.3 and the second damping orifice 2.3.4. The first pilot valve 2.3.1 is connected to the first damping orifice 2.3.2. The fourth damping orifice 2.4.4 is connected to the A1 oil circuit. The third damping orifice 2.4.2 is connected to the second cartridge valve 2.4.3 and the fourth damping orifice 2.4.4. The second pilot valve 2.4.1 is connected to the third damping orifice 2.4.2. The upstream pressure compensation valve 2.2 is connected to the inlet port P of the three-position four-way cartridge directional control valve 2.5. The P port of the three-position four-way cartridge directional control valve 2.5 is connected to the second cartridge valve 2.5.2, the third cartridge valve 2.5.3, the first electrically controlled three-position four-way solenoid directional valve 2.5.5, the first cartridge valve 2.5.1, the second cartridge valve 2.5.2, the third cartridge valve 2.5.3, and the fourth cartridge valve 2.5.4, respectively. The valves are connected in series, with two oil lines leading from the outlets of the second cartridge valve 2.5.2 and the third cartridge valve 2.5.3 to ports A1 and B1 respectively, connecting to the hydraulic cylinder. Port A of the first electrically controlled three-position four-way solenoid directional valve 2.5.5 is connected to the first cartridge valve 2.5.1 and the third cartridge valve 2.5.3 respectively, and port B of the first electrically controlled three-position four-way solenoid directional valve 2.5.5 is connected to the second cartridge valve 2.5.2 and the fourth cartridge valve 2.5.4 respectively. The main oil line of the two-position three-way directional control valve 2.6 is connected to the outlets of the second cartridge valve 2.5.2 and the third cartridge valve 2.5.3 respectively, and the control oil line of the two-position three-way directional control valve 2.6 is connected to the pilot oil line of the third cartridge valve 2.5.3. Check valve 2.7 is connected to the two-position three-way directional control valve 2.6.

[0056] In section III, check valve 3.1 is connected in series with pressure compensation valve 3.2 upstream of valve 3.2 in the LS oil circuit. Pressure compensation valve 3.2 upstream of valve 3.2 is connected to the rotary pump P2 oil circuit. Pilot-operated cartridge relief valve 3.3 at port B2 is connected to the B2 oil circuit, and pilot-operated cartridge relief valve 3.4 at port A2 is connected to the A2 oil circuit. The sixth damping orifice 3.3.4 is connected to the B2 oil circuit. The fifth damping orifice 3.3.2 is connected to the third cartridge valve 3.3.3 and the sixth damping orifice 3.3.4. The third pilot valve 3.3.1 is connected to the fifth damping orifice 3.3.2. The eighth damping orifice 3.4.4 is connected to the A2 oil circuit. The seventh damping orifice 3.4.2 is connected to the fourth cartridge valve 3.4.3 and the eighth damping orifice 3.4.4. The fourth pilot valve 3.4.1 is connected to the seventh damping orifice 3.4.2. The pressure compensation valve 2 (3.2) is connected to the inlet port P of the three-position four-way cartridge directional control valve 2 (3.5). The P port of the three-position four-way cartridge directional control valve 2 (3.5) is connected to the sixth cartridge valve (3.5.2), the seventh cartridge valve (3.5.3), and the second electrically controlled three-position four-way solenoid directional valve (3.5.5). The fifth cartridge valve (3.5.1), the sixth cartridge valve (3.5.2), the seventh cartridge valve (3.5.3), and the eighth cartridge valve (3.5.4) are connected in series. Two oil lines are led out from the outlet ports of the sixth cartridge valve (3.5.2) and the seventh cartridge valve (3.5.3) to ports A2 and B2, respectively, to connect to the hydraulic cylinder. The A port of the second electrically controlled three-position four-way solenoid directional valve (3.5.5) is connected to the fifth cartridge valve (3.5.1) and the seventh cartridge valve (3.5.3). The two electrically controlled three-position four-way solenoid directional valve 3.5.5B port is connected to the sixth cartridge valve 3.5.2 and the eighth cartridge valve 3.5.4 respectively. The right position main oil circuit of the two-position three-way directional control valve 3.6 is connected to the oil outlet A of the sixth cartridge valve 3.5.2, and the left position main oil circuit is connected to the integrated cartridge multi-way valve T port. The pilot oil circuit of the two-position three-way directional control valve 3.6 is connected to the sixth cartridge valve 3.5.2 and the seventh cartridge valve 3.5.3. The main oil circuit of the two-position three-way directional control valve 3.7 is connected to the sixth cartridge valve 3.5.2 and the seventh cartridge valve 3.5.3. The control oil circuit of the two-position three-way directional control valve 3.7 is connected to the pilot oil circuit of the seventh cartridge valve 3.5.3. The four-way check valve 3.8 is connected to the two-position three-way directional control valve 3.7.

[0057] In the fourth section, the pilot-operated proportional pressure reducing valve 4.1 is connected to the external control port X, the lower position (machine head rotation) of the proportional directional control valve 4.2 is connected to the pilot-operated proportional pressure reducing valve 4.1, the upper position of the proportional directional control valve 4.2 is connected to the pilot-operated proportional pressure reducing valve 4.3, and the pilot-operated proportional pressure reducing valve 4.3 is connected to the external drain port Y.

[0058] In section V, the variable signal controller 5.1 is connected to the pilot-operated proportional pressure reducing valve 1 4.1, the pilot-operated proportional pressure reducing valve 2 4.3, the third electrically controlled three-position four-way solenoid directional valve 5.2.5, the ninth cartridge valve 5.2.1, the tenth cartridge valve 5.2.2, the eleventh cartridge valve 5.2.3, and the twelfth cartridge valve 5.2.4; the valve upstream pressure compensation valve 3 5.3 is connected to the three-position four-way cartridge directional control valve 3 5.2; and the check valve 5 5.4 is connected to the valve upstream pressure compensation valve 3 5.3 and the LS oil circuit.

[0059] In section VI, check valve 6.1 connects to the LS oil circuit and the upstream pressure compensation valve 6.2. The upstream pressure compensation valve 6.2 is connected to the rotary pump P2 oil circuit. Pilot-operated cartridge relief valve 6.3 (port B3) is connected to the B3 oil circuit, and pilot-operated cartridge relief valve 6.4 (port A3) is connected to the A3 oil circuit. The tenth damping orifice 6.3.4 is connected to the B3 oil circuit. The ninth damping orifice 6.3.2 is connected to the fifth cartridge valve 6.3.3 and the tenth damping orifice 6.3.4. The fifth pilot valve 6.3.1 is connected to the ninth damping orifice 6.3.2. The twelfth damping orifice 6.4.4 is connected to the A3 oil circuit. The eleventh damping orifice 6.4.2 is connected to the sixth cartridge valve 6.4.3 and the twelfth damping orifice 6.4.4. The sixth pilot valve 6.4.1 is connected to the eleventh damping orifice 6.4.2. The pressure compensation valve 6.2 is connected to the inlet port P of the three-position four-way cartridge directional control valve 6.5. The P port of the three-position four-way cartridge directional control valve 6.5 is connected to the fourteenth cartridge valve 6.5.2, the fifteenth cartridge valve 6.5.3, the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5, the thirteenth cartridge valve 6.5.1, the fourteenth cartridge valve 6.5.2, the fifteenth cartridge valve 6.5.3, and the sixteenth cartridge valve 6.5.4, respectively. The valves are connected in series, and two oil lines are led out from the oil outlets of the fourteenth cartridge valve 6.5.2 and the fifteenth cartridge valve 6.5.3 to the A3 and B3 ports respectively to connect to the oil cylinder. The A port of the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 is connected to the thirteenth cartridge valve 6.5.1 and the fifteenth cartridge valve 6.5.3 respectively, and the B port of the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 is connected to the fourteenth cartridge valve 6.5.2 and the sixteenth cartridge valve 6.5.4 respectively.

[0060] The three-position four-way cartridge directional control valves (2.5, 3.5, 6.5) in sections II, III, and VI use spool feedback cartridge valves; while the three-position four-way cartridge directional control valve 5.2 in section V uses proportional three-position four-way pilot control, and the cartridge valve is a standard cartridge valve. At the same time, the valve spool displacement is collected to the variable signal controller 5.1, and after being amplified, the corresponding electrical signals are output to the pilot-operated proportional pressure reducing valve 1 4.1, the pilot-operated proportional pressure reducing valve 2 4.3, and the third electrically controlled three-position four-way solenoid directional valve 5.2.5.

[0061] The following will explain the specific working principle of the integrated cartridge multi-way valve: The push-pull pump and rotary pump of the integrated cartridge multi-way valve enter the P1 and P2 oil circuits of the integrated cartridge multi-way valve respectively, ensuring the individual and combined operation of the machine head and the main top. When needed, the corresponding working state is introduced to avoid the phenomenon that the hydraulic pump still works at a large displacement when the actuator is not moving, thereby reducing the energy loss of the hydraulic system.

[0062] When the pipe jacking machine head is working, the rotary pump is turned on, and high-pressure oil flows through... Figure 1 When the first electrically controlled three-position four-way solenoid directional valve 2.5.5 is de-energized, P, T, A, and B are not connected. At this time, the three-position four-way cartridge directional control valve 2.5 is closed, belonging to the O-type function of the neutral position. If the first electrically controlled three-position four-way solenoid directional valve 2.5.5 is energized in its upper position, the pilot oil circuit connects the first cartridge valve 2.5.1 and the third cartridge valve 2.5.3, which are closed. The second cartridge valve 2.5.2 and the fourth cartridge valve 2.5.4 are open. At this time, the oil flows through port P to port A1, thus entering the actuator motor. If the first electrically controlled three-position four-way solenoid directional valve 2.5.5 is energized in its lower position, the oil flows through port P to port B. The principle is the same, so it will not be repeated. Meanwhile, the pilot-operated cartridge relief valve 2.3 at port B1 and the pilot-operated cartridge relief valve 2.4 at port A1 are connected to the working oil circuits A1 and B1 respectively, ensuring that each working oil circuit of this integrated cartridge multi-way valve is not overloaded. The second damping orifice 2.3.4 and the fourth damping orifice 2.4.4 are respectively drawn from the high-pressure oil on the load side. The first pilot valve 2.3.1 and the second pilot valve 2.4.1 control the opening of their respective relief valves. Simultaneously, the first damping orifice 2.3.2 and the third damping orifice 2.4.2 are connected to the rear end of the main valve core, which eliminates pressure fluctuations, reduces impact, and ensures smooth valve core opening. When the first pilot valve 2.3.1 and the second pilot valve 2.4.1 reach their opening pressure, a pressure difference is generated on both sides of the main valve core, causing the main valve core to open and the relief valve to open, thus achieving overload protection.

[0063] When the main jacking machine is working, the push-pull pump is turned on, and high-pressure oil flows through... Figure 1When the oil enters the third section through port b, the main top valve enters the working state. At this time, if the second electrically controlled three-position four-way solenoid directional valve 3.5.5 is not energized, then P, T, A, and B are not connected. At this time, the three-position four-way cartridge directional control valve 3.5 is in the closed state, belonging to the O-type function of the middle position. If the second electrically controlled three-position four-way solenoid directional valve 3.5.5 is energized in the upper position, then the pilot oil circuit connects the fifth cartridge valve 3.5.1 and the seventh cartridge valve 3.5.3. These two cartridge valves are in the closed state, while the sixth cartridge valve 3.5.2 and the eighth cartridge valve 3.5.4 are in the open state. At this time, the oil enters through port P. The oil enters through port A2, thus entering the actuator motor. If the second electrically controlled three-position four-way solenoid directional valve 3.5.5 is energized in its lower position, the oil enters port B through port P of the second electrically controlled three-position four-way solenoid directional valve 3.5.5. The principle is the same, so it will not be described again. At the same time, the pilot-operated cartridge relief valve 3.3 at port B2 and the pilot-operated cartridge relief valve 3.4 at port A2 are connected to the working oil circuits A2 and B2 respectively, ensuring that each working oil circuit of this integrated cartridge multi-way valve is not overloaded. The sixth damping orifice 3.3.4 and the eighth damping orifice 3.4.4 are respectively drawn from the high-pressure oil on the load side, the third pilot valve 3.3.1, and the fourth pilot valve 3.4. .1 Controls the opening of each relief valve. Simultaneously, the fifth damping orifice 3.3.2 and the seventh damping orifice 3.4.2 are connected to the rear end of the main valve core, eliminating pressure fluctuations, reducing impact, and ensuring smooth valve core opening. When the third pilot valve 3.3.1 and the fourth pilot valve 3.4.1 reach their opening pressure, a pressure difference is generated on the left and right sides of the main valve core, causing the main valve core to open and the relief valve to open, achieving overload protection. Simultaneously, a two-position three-way directional control valve 3.6 is connected to the oil circuit of the second electrically controlled three-position four-way solenoid directional valve 3.5.5A. This two-position three-way directional control valve 3.6 controls the left side... The oil circuit originates from oil circuit B2 on the right and from oil circuit A2 on the right. When the main jack advances, oil circuit A2 is filled with high-pressure oil and oil circuit B2 is filled with low-pressure oil. At this time, the two-position three-way directional control valve 2.6 is in the right position under the action of high-pressure oil, and its function is similar to that of a check valve. When the main jack retreats, oil circuit B2 is filled with high-pressure oil and oil circuit A2 is filled with low-pressure oil. At this time, the two-position three-way directional control valve 2.6 is in the left position under the action of high-pressure oil. At this time, the low-pressure oil in port A2 directly enters the return oil circuit of the integrated cartridge multi-way valve through the two-position three-way directional control valve 2.6. The return oil does not pass through the main valve core of the cartridge valve, which greatly reduces the back pressure when the main jack retreats.

[0064] When the head rotation speed decreases due to load changes, it is necessary to increase the oil supply to the head rotation to increase the speed and prevent the cutterhead from becoming stuck due to poor soil discharge. At this time, the integrated valves IV and V enter the working state. The high-pressure oil in the V section is drawn from the rotary pump. The variable signal controller 5.1 simultaneously sends signals to the pilot-operated proportional pressure reducing valve 4.1 and the third electrically controlled three-position four-way solenoid directional valve 5.2.5, pushing the proportional directional control valve 4.2 to the lower position to enter the working state. At this time, the high-pressure oil passes through the V section and enters the directional control valve of the IV section, and then enters the one-way valve 2.7 in the II section. After passing through the two-position three-way directional control valve 2.6, it enters the high-pressure oil side, realizing the pressurization and confluence of the head rotation, thereby achieving the purpose of increasing the head rotation speed.

[0065] When the main jack's advancing or retracting speed is slow, the flow rate needs to be increased to increase the main jack's movement speed. At this time, the variable signal controller 5.1 simultaneously sends signals to the pilot-operated proportional pressure reducing valve 4.3 and the third electrically controlled three-position four-way solenoid directional valve 5.2.5, pushing the proportional directional control valve 4.2 to enter the working state. At this time, the high-pressure oil passes through the V section and enters the directional control valve of the IV section, and then enters the one-way valve 3.8 in the III section. After passing through the two-position three-way directional control valve 3.7, it enters the high-pressure oil side, realizing the pressurized confluence of the main jack's advancing and retracting, thereby achieving the purpose of increasing the main jack's extension and retraction speed.

[0066] When correction or intermediate motion is required, high-pressure oil is used... Figure 1When the d-port of the rotary valve enters the VI section, the rotary valve enters the working state. If the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 is not energized, then P, T, A, and B are not connected. At this time, the three-position four-way cartridge directional control valve 6.5 is in the closed state, belonging to the O-type function of the neutral position. If the upper position of the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 is energized, the pilot oil circuit connects the thirteenth cartridge valve 6.5.1 and the fifteenth cartridge valve 6.5.3, which are in the closed state. The fourteenth cartridge valve 6.5.2 and the sixteenth cartridge valve 6.5.4 are in the open state. At this time, the oil flows through the P-port of the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 into the A-port, thus entering the actuator motor. If the lower position of the fourth electrically controlled three-position four-way solenoid directional valve 6.5.5 is energized, the oil flows through the P-port into the B-port. The principle is the same, so it will not be repeated. Meanwhile, the pilot-operated cartridge relief valve 6.3 at port B3 and the pilot-operated cartridge relief valve 6.4 at port A3 are connected to the working oil circuits A3 and B3 respectively, ensuring that each working oil circuit of this integrated cartridge multi-way valve is not overloaded. The tenth damping port 6.3.4 and the twelfth damping port 6.4.4 are respectively drawn from the high-pressure oil on the load side. The fifth pilot valve 6.3.1 and the sixth pilot valve 6.4.1 control the opening of their respective relief valves. Simultaneously, the ninth damping port 6.3.2 and the eleventh damping port 6.4.2 are connected to the rear end of the main valve core, which eliminates pressure fluctuations, reduces impact, and ensures smooth valve core opening. When the fifth pilot valve 6.3.1 and the sixth pilot valve 6.4.1 reach their opening pressure, a pressure difference is generated on both sides of the main valve core, causing the main valve core to open and the relief valve to open, thus achieving overload protection.

[0067] The overall working principle of the integrated cartridge multi-way valve when the cartridge valve starts working is as follows:

[0068] Pressure compensation valve: When one or more electrically controlled cartridge multi-way valves operate simultaneously, the load pressure is transmitted to one side of the spring chamber of the pressure compensation valve. At this time, the negative feedback of the valve core automatically adjusts the flow rate of the hydraulic oil flowing through the reversing valve, ensuring that the pressure difference across the valve port remains essentially constant. Therefore, under pressure compensation, the flow rate through each reversing valve remains relatively constant, allowing the flow rate into each reversing valve to be proportional to the input current signal of the pilot proportional pressure reducing valve controlling it. When a control current signal is input, a corresponding flow signal is output, corresponding to the valve opening an appropriate opening area. This achieves independent, remote pilot control unaffected by external load changes.

[0069] When each directional control valve is in the neutral position, the valve core of each valve is not connected to either port P or ports A and B. At this time, the oil from the pressure chamber acts on the left chamber of the pressure compensation valve, so it is only necessary to overcome the spring force on the right side of the pressure compensation valve. The spring of the pressure compensation valve causes the valve core to shift to the right through a balancing movement and eventually stop at a balanced position. The oil in the pressure chamber is connected to the T oil circuit through the valve core of the pressure compensation valve. At this time, the oil circuit pressure of the load feedback is the return oil pressure. This pressure makes the tilt angle of the control variable pump close to 0 degrees, and the hydraulic pump is supplying oil at the minimum displacement. The flow rate output by the pump is only the flow rate required for system leakage, that is, it is in a low-pressure unloading state; thus minimizing the power consumption of the system and achieving the requirements of energy saving and environmental protection.

[0070] When the pilot-operated solenoid directional valve is energized and begins to work, the cartridge valve core of the directional coupling gradually moves, allowing hydraulic oil to enter the working oil circuit. The oil pumped by the hydraulic pump enters the actuator through the throttle orifice of the pressure compensation valve and the throttle groove of the cartridge valve core. At this time, the hydraulic oil pressure is obtained through the load pressure of the actuator via the load-sensitive LS shuttle valve. This pressure is fed back to the control chamber on one side of the hydraulic pump through the load-sensitive circuit LS, causing the tilt angle of the hydraulic pump to gradually increase or decrease, and the output flow of the hydraulic pump to increase or decrease accordingly. As the valve core moves further to the end of its stroke, the throttling groove of the cartridge valve core also reaches its maximum opening. The actuator then moves against the external load, gradually increasing the working pressure of the hydraulic system. This external load pressure is quickly fed back to the pressure compensation valve and transmitted to the pump's control chamber via the LS oil circuit. At this point, the pressure compensation valve reaches a new equilibrium through a spring movement, and the hydraulic pump gradually adjusts the swashplate angle to ensure the output flow is the maximum required by the system. We can assume the initial pressure differential setting of the pressure compensation valve is 1 MPa. When the pump's output flow increases, the pressure differential between the left and right ends of the pressure compensation valve decreases. The valve core then breaks the equilibrium and moves left and right to select a new equilibrium position until the pressure differential gradually returns to approximately 1 MPa. The pressure compensation valve thus automatically adjusts and compensates for the system pressure by moving left and right, keeping the pressure differential at the main valve core opening constant. Since the flow rate is only related to the valve opening area, the corresponding output flow rate remains relatively stable.

[0071] When using a three-position four-way cartridge directional control valve, the cartridge valves at ports A and B can form a type B half-bridge similar to a bridge circuit. This half-bridge has moderate gain, large stability margin, and low process requirements. At the same time, the flow gain can directly affect the response speed of the circuit, thus playing a crucial role in the overall performance of the valve.

[0072] like Figure 4 As shown, the cartridge valve adopts feedback closed-loop control to improve the overall valve core displacement accuracy. A pilot proportional electromagnet 7.1 is located at the leftmost end of the valve body 7.3, and the push rod 7.2 is connected to the pilot proportional electromagnet 7.1.

[0073] The left end of the push rod 7.2 is connected to the pilot proportional electromagnet 7.1, and the right end is connected to the pilot valve core 7.5;

[0074] The pilot valve core 7.5 has springs 7.6 on both the left and right sides, which are installed inside the cartridge valve core 7.4. The pilot oil circuit A port is connected to the A port of the three-position four-way cartridge directional control valve (2.5 / 3.5 / 6.5), and the pilot oil circuit B port is connected to the B port of the three-position four-way cartridge directional control valve (2.5 / 3.5 / 6.5).

[0075] The cartridge valve core 7.4 is installed inside the valve body 7.3. Its inner side contacts the pilot valve core 7.5, and its outer side contacts the valve body 7.3 and can move left and right. The rightmost end is the high-pressure oil, which is connected to the main oil circuit and flows to the actuator.

[0076] The left side of the cartridge valve fixing plate 7.7 is connected to the valve body 7.3 and fixed in place. A round hole is reserved in the center for the left and right movement of the cartridge valve core 7.4. At the same time, the right side is used to fix the return spring 7.9.

[0077] The inner side of the cartridge valve main body 7.8 is in contact with the cartridge valve core 7.4, and its outer side is connected to the valve body 7.3 by threads. It has an oil passage hole A and an oil sealing area.

[0078] The reset spring 7.9 is sleeved on the right end of the cartridge valve core 7.4, its left end is fixed to the right side of the cartridge valve fixing plate 7.7, and its right end is connected to the cartridge valve main body 7.8, which is used to push the cartridge valve main body 7.8 to reset.

[0079] The pilot valve core 7.5 adopts a spool valve, which is a conversion and amplification element that can convert the input valve core displacement into a hydraulic signal and output to control the flow rate of the main oil circuit.

[0080] The specific working principle of this cartridge valve is as follows:

[0081] When the pilot proportional electromagnet 7.1 is not energized, both ports A and B of the pilot valve core 7.5 are closed, the pilot valve core 7.5 has no flow output, and the cartridge valve core 7.4 only has spring force.

[0082] When the pilot proportional electromagnet 7.1 is energized, it drives the pilot valve core 7.5 to move by a corresponding displacement. At this time, the pilot oil circuit of the cartridge valve is connected to the three-position four-way cartridge directional control valves (2.5 / 3.5 / 6.5) in the above-mentioned connections. At this time, the oil enters the pilot valve core 7.5, which has a pilot oil guide groove. The pilot oil can enter the cartridge valve core 7.4 through the flow channel on the pilot valve core 7.5, and then enter the spring side of the cartridge valve core 7.4. Together with the spring force, it controls the opening degree of the cartridge valve core 7.4, thereby controlling the amount of oil flowing from port P to port A. At the same time, the movement of the cartridge valve core 7.4 will drive the opening and closing of the pilot oil opening of the pilot valve core 7.5. When the cartridge valve core 7.4 moves by displacement x, the pilot valve core 7.5 will close the opening by displacement xi accordingly, thus forming a closed-loop feedback to eliminate deviation and accurately control the flow rate of hydraulic oil.

[0083] In this control process, the output displacement of the cartridge valve spool 7.4 can automatically, quickly, and accurately reproduce the changes in the input displacement. The displacement of the cartridge valve spool 7.4 is constantly compared with the displacement of the pilot valve spool 7.5 (spool valve) to obtain the displacement deviation between the two. This deviation is the opening degree of the pilot valve spool 7.5 (spool valve). When the pilot valve spool 7.5 has a certain opening degree, a certain amount of hydraulic oil will enter the cartridge valve spool 7.4. The movement of the cartridge valve spool 7.4 will in turn drive the pilot valve spool 7.5 (spool valve) to close, until the displacement of the cartridge valve spool 7.4 is consistent with the displacement of the pilot valve spool 7.5 and stops.

[0084] The above process demonstrates that, through a series of control actions such as the pilot valve and cartridge valve, precise control of all functions of the pipe jacking machine is achieved, thereby greatly improving the operational performance of the pipe jacking machine.

[0085] Of course, the above description is not a limitation on the dedicated integrated valve for pipe jacking machines, and the present invention is not limited to the examples mentioned above. Those skilled in the art can easily understand the working principle, and can also make different modifications or alterations based on it. It is impossible to list all integrated valves with similar principles here. Therefore, any corresponding modifications, fine-tuning, changes, or equivalent substitutions made by those skilled in the art based on this should be included within the scope of the claims of the present invention.

Claims

1. An integrated cartridge-type multi-way valve for a pipe jacking machine, characterized in that: It consists of six valves I, II, III, IV, V, and VI connected in parallel. Among them, valve I is a safety control valve, valve II is a machine head rotation control valve, valve III is a main top advance / retreat control valve, valve IV is a pressurization and flow directional control valve, valve V is a machine head main top pressurization and flow directional valve, and valve VI is a correction / relay control valve. In the first section, the valve's built-in filter one is connected to the LS oil circuit and in series with the LS speed control valve, which is connected to the valve block's main return oil circuit T channel; the neutral position P1 push-pull pump unloading valve is connected to the rotary pump's high-pressure oil inlet P2 and to the return oil circuit T channel; the neutral position P2 rotary pump unloading valve is connected to the push-pull pump's high-pressure oil inlet P1 and to the return oil circuit T channel; the X oil circuit pressure reducing valve is connected to the P2 oil circuit and, together with the valve's built-in filter two, is connected to the X oil circuit; the LS overflow valve is connected to the LS oil circuit and the T channel. In the second, third, and sixth sections, a check valve is connected to the LS oil circuit and is connected in series with the upstream pressure compensation valve; the upstream pressure compensation valve is connected to the rotary pump P2 oil circuit; the B-port pilot-operated cartridge relief valve is connected to the corresponding B oil circuit of each section, and the A-port pilot-operated cartridge relief valve is connected to the corresponding A oil circuit of each section; the upstream pressure compensation valve is connected to the inlet P port of the three-position four-way cartridge directional control valve, and the outlet ports of the second and third cartridge valves of the three-position four-way cartridge directional control valve are respectively connected to the corresponding A and B oil circuits of each section; The second section further includes a two-position three-way directional control valve, whose main oil circuit is connected to the oil outlets of the second and third cartridge valves of the three-position four-way cartridge directional control valve, respectively. The control oil circuit of the two-position three-way directional control valve is connected to the pilot oil circuit of the third cartridge valve of the three-position four-way cartridge directional control valve, and the check valve is connected to the two-position three-way directional control valve.

2. The integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 1, characterized in that: The third section also includes a two-position three-way directional control valve 2 whose right-position main oil circuit is connected to the outlet port A of the second cartridge valve of the three-position four-way cartridge directional control valve, and whose left-position main oil circuit is connected to the port T of the integrated cartridge multi-way valve. The pilot oil circuit of the two-position three-way directional control valve 2 is connected to the second and third cartridge valves of the three-position four-way cartridge directional control valve. The main oil circuit of the two-position three-way directional control valve 3 is connected to the second and third cartridge valves of the three-position four-way cartridge directional control valve, and its control oil circuit is connected to the pilot oil circuit of the third cartridge valve of the three-position four-way cartridge directional control valve. The check valve 4 is connected to the two-position three-way directional control valve 3.

3. The integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 1, characterized in that: In the fourth section, the pilot-operated proportional pressure reducing valve one is connected to the external control port X, the lower position of the proportional directional control valve is connected to the pilot-operated proportional pressure reducing valve one, the upper position of the proportional directional control valve is connected to the pilot-operated proportional pressure reducing valve two, and the pilot-operated proportional pressure reducing valve two is connected to the external drain port Y.

4. The integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 1, characterized in that: In the fifth section, the variable signal controller is connected to the three-position four-way cartridge directional control valve and to the pilot-operated proportional pressure reducing valve one and the pilot-operated proportional pressure reducing valve two in the fourth section. The valve upstream pressure compensation valve three is connected to the three-position four-way cartridge directional control valve three. The one-way valve five connects the valve upstream pressure compensation valve three and the LS oil circuit.

5. An integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 1, characterized in that: The A-port pilot-operated cartridge relief valve and the B-port pilot-operated cartridge relief valve have the same structure, specifically including a pilot valve, a first damping orifice, a cartridge valve, and a second damping orifice; the second damping orifice is connected to the B oil circuit, the first damping orifice is connected to the cartridge valve and the second damping orifice, and the pilot valve is connected to the first damping orifice.

6. An integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 1 or 4, characterized in that: The three-position four-way cartridge directional control valve includes a first cartridge valve, a second cartridge valve, a third cartridge valve, a fourth cartridge valve, and an electrically controlled three-position four-way solenoid directional valve; the first cartridge valve, the second cartridge valve, the third cartridge valve, and the fourth cartridge valve are connected in series, the A port of the electrically controlled three-position four-way solenoid directional valve is connected to the first cartridge valve and the third cartridge valve respectively, the B port of the electrically controlled three-position four-way solenoid directional valve is connected to the second cartridge valve and the fourth cartridge valve respectively, wherein the P port of the three-position four-way cartridge directional control valve is connected to the second cartridge valve, the third cartridge valve, and the electrically controlled three-position four-way solenoid directional valve respectively; Among them, the three-position four-way cartridge directional control valves in the second, third and sixth links lead out two oil lines from the oil outlets of the second and third cartridge valves to port A and port B respectively to connect to the oil cylinder.

7. An integrated cartridge-type multi-way valve for a pipe jacking machine according to claim 6, characterized in that: The cartridge valve includes a pilot proportional electromagnet, a push rod, a valve body, a cartridge valve core, a pilot valve core, a spring, a cartridge valve fixing plate, a cartridge valve main body, and a return spring. The pilot proportional electromagnet is located at the leftmost end of the valve body, and the left end of the push rod is connected to the pilot proportional electromagnet, while the right end is connected to the pilot valve core. The pilot valve core is installed inside the integral cartridge valve core, and springs are provided at its left and right ends; The integral cartridge valve core is installed in the valve body, with its inner side contacting the pilot valve core and its outer side contacting the valve body. The left side of the cartridge valve fixing plate is fixedly connected to the valve body, and a circular hole is provided in the center of the plate. A return spring is fixed on the right side of the plate. The inner side of the cartridge valve main valve body is in contact with the integral cartridge valve core, and its outer side is threaded to the valve body. It has an oil passage hole A and an oil sealing area. The reset spring is sleeved on the right end of the integral cartridge valve core, its left end is fixed to the right side of the cartridge valve fixing plate, and its right end is connected to the main valve body of the cartridge valve.

Images