Plug-in mounting type priority diverter valve and hydraulic system

Abstract

The invention discloses a plug-in mounting type priority diverter valve and a hydraulic system. The plug-in mounting type priority diverter valve comprises a valve body, a valve sleeve assembly, a plug assembly, a spring seat, a spring and a diverter valve element assembly. An oil inlet, a first working oil port, a second working oil port and a feedback oil port are formed in the valve body; the valve sleeve assembly comprises a valve sleeve; the flow dividing valve element assembly comprises a flow dividing valve element and a variable damper, four axial throttling grooves are formed in the circumferential direction of the flow dividing valve element, a flow guiding annular groove is formed in the circumferential surface of the rear portion of the flow dividing valve element, a radial through hole is formed in the flow guiding annular groove, and an axial hole is formed in the surface of the rear end of the flow dividing valve element; the rear end of the flow dividing valve element and the inner side wall of the valve body form a pilot control cavity. According to the multi-way valve, the problem of system complexity caused by an independent priority valve is effectively solved, the priority shunting function is integrated in the multi-way valve, and external pipeline connection is reduced. The plug-in mounting type valve sleeve assembly achieves flow channel machining and valve body separation, machining difficulty is reduced, and production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic control, and in particular to a plug-in priority diverter valve and a hydraulic system. Background Art

[0002] In construction machinery such as backhoe loaders, load-sensing hydraulic systems typically utilize a standalone priority valve to ensure priority hydraulic oil supply to the steering system. This traditional solution suffers from significant issues such as low system integration and complex piping layouts. Independent priority valves not only increase pressure loss along the system but also increase overall material costs, a particular problem in compact construction machinery. With the growing demand for miniaturized equipment driven by urbanization and the industry's trend toward cost reduction and efficiency improvement, traditional independent priority valve solutions are no longer able to meet the requirements of modern construction machinery for highly integrated, standardized, and maintainable hydraulic systems. Existing differentially compensated priority valves, when used as standalone components, suffer from large space requirements and low system integration. This is particularly true in compact hydraulic systems, where complex piping layouts are a significant issue. Furthermore, traditional priority valves exhibit numerous deficiencies in standardized selection, valve body processing, assembly efficiency, and maintainability. These issues severely hinder the development of more efficient and compact hydraulic systems in construction machinery. Summary of the Invention

[0003] In view of this, the present invention provides a plug-in priority diverter valve, which has the advantages of improving system integration, simplifying pipeline layout, reducing material costs, and improving assembly efficiency and maintainability.

[0004] To achieve the above object, the present invention provides the following technical solutions: A plug-in priority diverter valve comprises a valve body, a valve sleeve assembly, a plug assembly, a spring seat, a spring and a diverter valve core assembly.

[0005] Among them, the valve body is provided with an oil inlet, a first working oil port, a second working oil port and a feedback oil port; the diverter valve core assembly is installed inside the valve sleeve; the valve sleeve assembly includes: a valve sleeve, which is provided with six first radial holes, six second radial holes, a first fixed damping hole and a second fixed damping hole; the diverter valve core assembly includes: a diverter valve core and a variable damping, four axial throttling grooves are provided on the circumference of the diverter valve core, a guide annular groove is provided on the rear circumferential surface of the diverter valve core, a radial through hole is provided on the guide annular groove, an axial hole is provided on the rear end surface of the diverter valve core, and the rear end of the diverter valve core and the inner wall of the valve body constitute a pilot control chamber.

[0006] Preferably, the valve sleeve assembly further includes a first O-ring, a second O-ring, a third O-ring, a first retaining ring, a second retaining ring and a Gley ring; the valve sleeve surface is provided with a first annular groove, a second annular groove, a third annular groove, a fourth annular groove, a fifth annular groove and a sixth annular groove spaced apart in the axial direction, the Gley ring is installed on the first annular groove, the second O-ring and the first retaining ring are both installed on the second annular groove, a third radial hole is provided on the fifth annular groove, and the third O-ring and the second retaining ring are both installed on the sixth annular groove.

[0007] Preferably, a conical surface is provided at the rear of the diverter valve core.

[0008] Preferably, the plug assembly includes a screw plug and a fourth O-ring, the screw plug is provided with a sealing annular groove, and the fourth O-ring is installed on the sealing annular groove.

[0009] Preferably, the spring seat is installed on the screw plug, and the spring is installed between the spring seat and the diverter valve core.

[0010] The present invention also proposes a hydraulic system for an excavator loader, comprising a cartridge-type priority diverter valve, a load-sensing pump, an excavation valve, a loading valve, a steering gear, a steering cylinder and an oil tank according to any one of the above embodiments; the loading valve is integrated with a cartridge-type priority diverter valve, a steering relief valve, a shuttle valve, an Ls relief valve and a constant flow valve; and the excavation valve is integrated with a mid-position unloading valve.

[0011] Preferably, the socket of the neutral unloading valve is the same as the socket of the cartridge-type priority diverter valve.

[0012] The beneficial effects of the present invention are as follows: Compared with the prior art, the present application effectively solves the system complexity problem caused by independent priority valves, integrates the priority diversion function inside the multi-way valve, and reduces external pipeline connections. The plug-in valve sleeve assembly separates the flow channel processing from the valve body, reducing processing difficulty and improving production efficiency. The composite throttling structure of the diverter valve core realizes the coordinated control of the main oil circuit and the pilot oil circuit, simplifying the hydraulic system structure while ensuring the steering priority function. The standardized socket design makes the structure adaptable to systems with different flow specifications, and functional expansion can be achieved by replacing the valve sleeve assembly.

[0013] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a cross-sectional view of the cartridge-type priority diverter valve of the present invention; Figure 2 is a front view of the valve sleeve of the present invention; Figure 3yes Figure 2 Cross-sectional view along line AA; Figure 4 It is a structural schematic diagram of the diverter valve core of the present invention; Figure 5 This is a simplified hydraulic principle diagram of the hydraulic system of the backhoe loader of the present invention; Figure 6 It is a schematic diagram of the principle of the plug-in priority diverter valve of the present invention.

[0015] Reference numerals: 1. Valve sleeve assembly; 101. Valve sleeve; 102. First O-ring; 103. Second O-ring; 104. First retaining ring; 105. Gly ring; 106. Third O-ring; 107. Second retaining ring; 101.1. First radial hole; 101.2. Second radial hole; 101.3. First fixed damping hole; 101.4. Second fixed damping hole; 101.5. First annular groove; 101.6. Second annular groove; 101.7. Third annular groove; 101.8. Fourth annular groove; 101.9. Fifth annular groove; 101.10. Sixth annular groove; 101.11. Third radial hole; 2. Plug assembly; 201. Screw plug; 202. Fourth O-ring; 3. Spring seat; 4. Spring; 5. Diverter valve core assembly; 501. Diverter valve core; 502. Variable damping; 501.1. Axial throttling groove; 501.2. Guide annular groove; 501.3. Radial through hole; 501.4. Axial hole; 501.5. Conical surface; 6. Valve body; 601. Oil inlet; 602. First working oil port; 603. Second working oil port; 604. Feedback oil port; 605. Pilot control chamber. DETAILED DESCRIPTION

[0016] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0018] Reference below Figures 1 to 6A cartridge-type priority diverter valve in an embodiment of the present invention is described.

[0019] The embodiment of the present application discloses a plug-in priority diverter valve, comprising: a valve body 6, a valve sleeve 101 assembly 1, a plug assembly 2, a spring seat 3, a spring 4 and a diverter valve core assembly 5; the valve body 6 is provided with an oil inlet 601, a first working oil port 602, a second working oil port 603 and a feedback oil port 604; the diverter valve core assembly 5 is installed inside the valve sleeve 101; the valve sleeve 101 assembly 1 comprises: a valve sleeve 101, which is provided with six first radial holes 101.1, six second radial holes 101.2, a first fixed damping hole 101.3 and a second fixed damping hole 101.4; the diverter valve core assembly 5 includes: a diverter valve core 501 and a variable damping 502, four axial throttling grooves 501.1 are arranged on the circumference of the diverter valve core 501, a guide annular groove 501.2 is arranged on the rear circumferential surface of the diverter valve core 501, and a radial through hole 501.3 is arranged on the guide annular groove 501.2, and an axial hole 501.4 is opened on the rear end surface of the diverter valve core 501, and the rear end of the diverter valve core 501 and the inner wall of the valve body 6 constitute a pilot control chamber 605.

[0020] Among them, the valve sleeve 101 component 1 is a structural unit including the valve sleeve 101 and the damping hole. The diameter of the fixed damping hole can be adjusted according to the flow demand of the system. By replacing drill bits of different specifications, the aperture matching can be achieved to realize the universal adaptation of the pressure regulation function. The axial throttling groove 501.1 of the diverter valve core assembly 5 is four longitudinal grooves evenly distributed along the circumference of the valve core, which are used to establish the main oil circuit throttling path and adjust the flow distribution ratio by changing the groove width or depth. The guide annular groove 501.2 is an annular groove surrounding the rear part of the valve core. It cooperates with the radial through hole 501.3 to form a pilot oil channel, which transmits the feedback oil circuit pressure to the axial hole 501.4. The pilot control chamber 605 is a closed space surrounded by the rear end face of the diverter valve core 501 and the inner wall of the valve body 6. Specifically, it can form a variable volume cavity by controlling the axial displacement of the valve core, which is used to balance the liquid pressure and the spring 4 force.

[0021] Specifically, after the hydraulic oil enters the valve body 6 from the oil inlet 601, it flows in two ways. The main oil circuit enters the axial throttle groove 501.1 through the radial hole of the valve sleeve 101, and flows to the working oil port after throttling. The pilot oil circuit enters the axial hole 501.4 through the radial through hole 501.3 of the guide annular groove 501.2, and reaches the pilot control chamber 605 after throttling by the variable damping 502 to form a control pressure. This control pressure pushes the diverter valve core 501 to move axially, changing the throttle groove opening to adjust the flow distribution. When the steering system is working, the pressure of the feedback oil port 604 acts on the spring 4 chamber through the fixed damping hole, and together with the pressure of the pilot control chamber 605, balances the spring 4 force to achieve steering-priority flow distribution. The valve sleeve 101 is assembled on the valve body 6 as an independent component, and its internal flow channel and damping hole processing are completed in the valve sleeve 101, reducing the difficulty of valve body 6 processing.

[0022] Compared to existing technologies, traditional priority valves require complex flow channels to be machined within the valve body 6. This solution integrates these channels within a replaceable valve sleeve 101 assembly 1, eliminating the need for standardized receptacles within the valve body 6. While the existing priority valve and multi-way valve are separate structures, this solution achieves functional integration through a plug-in design, eliminating connecting piping. While traditional structures require individual damping orifices for each valve body 6, this solution utilizes the interchangeability of the valve sleeve 101 assembly 1 to enable rapid adjustment of the damping orifice diameter to accommodate diverse system requirements.

[0023] Through the above technical solution, the present application effectively solves the system complexity problem caused by independent priority valves, integrates the priority diversion function inside the multi-way valve, and reduces external pipeline connections. The plug-in valve sleeve 101 component 1 realizes the separation of flow channel processing from the valve body 6, reducing processing difficulty and improving production efficiency. The composite throttling structure of the diverter valve core 501 realizes the coordinated control of the main oil circuit and the pilot oil circuit, simplifying the hydraulic system structure while ensuring the steering priority function. The standardized socket design makes the structure adaptable to systems with different flow specifications, and functional expansion can be achieved by replacing the valve sleeve 101 component 1.

[0024] In some embodiments, for example Figure 1 、 Figure 2 and Figure 3As shown, the valve sleeve 101 assembly 1 also includes a first O-ring 102, a second O-ring 103, a third O-ring 106, a first retaining ring 104, a second retaining ring 107 and a Gly ring 105; the surface of the valve sleeve 101 is axially spaced apart with a first annular groove 101.5, a second annular groove 101.6, a third annular groove 101.7, a fourth annular groove 101.8, a fifth annular groove 101.9 and a sixth annular groove 101.10, the Gly ring 105 is installed on the first annular groove 101.5, the second O-ring 103 and the first retaining ring 104 are both installed on the second annular groove 101.6, the fifth annular groove 101.9 is provided with a third radial hole 101.11, and the third O-ring 106 and the second retaining ring 107 are both installed on the sixth annular groove 101.10.

[0025] Among them, the Gly ring 105 is a sealing element made of a composite of polytetrafluoroethylene and rubber. Its wear resistance and low friction properties are suitable for dynamic sealing between the valve sleeve 101 and the valve body 6. The second O-ring 103 and the third O-ring 106 are elastic sealing rings with circular cross-sections. By cooperating with the retaining ring, they form a static sealing structure to prevent high-pressure oil from leaking from the gap between the valve sleeve 101 and the valve body 6. The first retaining ring 104 and the second retaining ring 107 are rigid limit rings with rectangular cross-sections. They are used to limit the axial deformation of the O-ring under high pressure and avoid sealing failure. The six annular grooves refer to the groove structure distributed axially along the outer surface of the valve sleeve 101. They are used to accurately install different sealing elements and correspond to the separated pressure chambers in the valve body 6.

[0026] Specifically, the Gly ring 105 installed in the first annular groove 101.5 forms a dynamic seal between the valve sleeve 101 and the valve body 6, adapting to the friction conditions during the reciprocating motion of the valve core. The second O-ring 103 in the second annular groove 101.6 is restricted in radial expansion by the first retaining ring 104, forming a high-pressure static seal in the middle area and isolating the pressure of the adjacent oil chambers. The third O-ring 106 in the sixth annular groove 101.10, combined with the second retaining ring 107, forms a terminal sealing barrier, preventing the intrusion of external contaminants and the leakage of internal oil. The axially spaced layout of the six annular grooves ensures that the first, second, and sixth annular grooves correspond to the dynamic sealing area, the intermediate static sealing area, and the terminal static sealing area, respectively, forming a three-stage progressive sealing system. The third annular groove 101.7, the fourth annular groove 101.8, and the fifth annular groove 101.9 serve as transition areas to prevent interference during the installation of sealing elements. This structure achieves modular assembly of seals through standardized slot design, simplifying the processing of the valve sleeve 101.

[0027] Through the above technical solution, this application solves the problem of insufficient sealing reliability when integrating a cartridge-type priority diverter valve into a multi-way valve inlet. The combination of the Gly Ring 105 and the retaining ring O-ring achieves a synergistic effect of dynamic and static sealing. The axially spaced arrangement of the six annular grooves completely isolates the different pressure oil chambers, preventing oil cross-contamination.

[0028] In some embodiments, for example Figure 1 and Figure 3 As shown, the rear portion of the diverter valve core 501 is provided with a tapered surface 501.5. The tapered surface 501.5 refers to a conical sealing surface machined from the rear portion of the diverter valve core 501. This tapered surface 501.5 forms a tapered sealing mating surface with the valve sleeve 101 or valve body 6, reducing frictional resistance by reducing the contact area.

[0029] Specifically, the conical surface 501.5 forms linear contact with the inner wall of the valve sleeve 101 during the axial movement of the valve core. When the steering system load pressure changes, the hydraulic pressure is transmitted to the pilot control chamber 605 through the guide annular groove 501.2 and the radial through-hole 501.3, pushing the conical surface 501.5 along the axis of the valve sleeve 101. The tapered nature of the conical surface 501.5 allows the valve core opening to adjust linearly with pressure changes, avoiding hydraulic shock caused by sudden changes in contact area. When the steering system is not in operation, the clearance between the conical surface 501.5 and the valve sleeve 101 limits leakage. At the same time, the force of spring 4 maintains the valve core at its maximum opening, ensuring flow in the working oil circuit.

[0030] Through the above-mentioned technical solution, this application achieves linear pressure-displacement control during the movement of the diverter valve core 501, improving the stability of the steering priority flow distribution. The sealing structure of the conical surface 501.5 effectively reduces the risk of valve core sticking, while the progressive throttling characteristic prevents the impact of hydraulic shock on the system. The combination of the pressure balance channel and the conical surface 501.5 ensures the valve core's rapid response under different operating conditions, enabling the reliable implementation of the steering system's priority oil supply function.

[0031] In some embodiments, for example Figure 1 As shown, the plug assembly 2 includes a screw plug 201 and a fourth O-ring 202. The screw plug 201 is provided with a sealing annular groove, into which the fourth O-ring 202 is mounted. The screw plug 201 is a cylindrical plug with external threads, which mate with the threaded holes in the valve sleeve 101 for axial positioning. The sealing annular groove is an annular groove provided on the outer cylindrical surface of the screw plug 201, which is used to restrict radial deformation of the seal. The fourth O-ring 202 is installed in the sealing annular groove, forming a bidirectional sealing interface.

[0032] Specifically, when the screw plug 201 is screwed into the threaded hole on the valve sleeve 101, the fourth O-ring 202 is radially compressed by the side wall of the sealing annular groove, causing elastic deformation to fill the gap between the groove body and the hole wall of the valve sleeve 101. Under the action of the hydraulic system pressure, the O-ring moves toward the bottom of the sealing annular groove, and the side wall of the groove body limits its excessive deformation, preventing the high-pressure oil from squeezing out the seal. The threaded connection structure enables the plug assembly 2 to form a self-locking mechanism. The axial force generated when the system pressure increases can enhance the preload force of the threaded pair and avoid the formation of gaps in the sealing interface. The geometric dimensions of the sealing annular groove are precisely matched to the cross-section of the O-ring to ensure that the seal can be freely compressed without excessive distortion.

[0033] Through the above technical solution, the present application achieves a self-centering seal for the plug assembly 2 during axial assembly, eliminating the end face machining precision required for traditional flat seals. The matching structure of the sealing annular groove and the O-ring forms a pressure-adaptive sealing mechanism, effectively maintaining stable sealing performance.

[0034] In some embodiments, for example Figure 1 As shown, spring seat 3 is mounted on screw plug 201, and spring 4 is installed between spring seat 3 and diverter valve core 501. Spring seat 3 is a rigid support component used to secure the end of spring 4. Specifically, it can be implemented as a stepped shaft structure. Its outer diameter forms a clearance fit with the inner hole of screw plug 201, and the inner hole forms a clearance fit with the outer diameter of spring 4, thereby limiting the radial displacement of spring 4.

[0035] Specifically, the spring seat 3 is fixed in the inner hole of the screw plug 201 to form an axial positioning reference surface. One end of the spring 4 abuts the end face of the spring seat 3, and the other end contacts the rear end face of the diverter valve core 501. When the hydraulic fluctuation causes the diverter valve core 501 to displace axially, the spring 4 undergoes elastic deformation between the fixed end of the spring seat 3 and the movable end of the valve core, and the radial displacement of the spring 4 is constrained by the rigid connection between the spring seat 3 and the screw plug 201. When the screw plug 201 is screwed into the valve sleeve 101, the contact position between its end face and the end face of the valve sleeve 101 determines the pre-compression amount of the spring 4. The initial load of the spring 4 can be accurately controlled by adjusting the screw-in depth of the screw plug 201. During the movement of the diverter valve core 501, the spring seat 3 acts as a fixed fulcrum, so that the force of the spring 4 always acts along the axis of the valve core, avoiding the lateral component of force causing the valve core to get stuck.

[0036] Through the above-mentioned technical solution, this application solves the problem of preload deviation caused by inconsistent installation and positioning references of spring 4, eliminates the interference of radial movement of spring 4 on the motion trajectory of the valve core, and achieves precise control of valve core displacement under high-vibration conditions. The modular design of spring seat 3 and screw plug 201 simplifies the assembly process. The preload calibration of spring 4 can be completed by adjusting the thread depth, improving production consistency. The axial alignment design of the diverter valve core 501 and spring 4 reduces the friction resistance of the kinematic pair and extends the service life of the valve.

[0037] The present invention also proposes a hydraulic system for an excavator loader, comprising a cartridge-type priority diverter valve, a load-sensing pump, an excavation valve, a loading valve, a steering gear, a steering cylinder and an oil tank as described in any one of the above embodiments; the loading valve is integrated with a cartridge-type priority diverter valve, a steering overflow valve, a shuttle valve, an Ls overflow valve and a constant flow valve; the excavation valve is integrated with a mid-position unloading valve.

[0038] The cartridge-type priority diverter valve is integrated within the loading valve. It prioritizes oil supply to the steering system through the interaction of the valve core's axial throttle groove 501.1 and the damping orifice. A load-sensing pump is a hydraulic power source that adjusts its output flow rate based on system pressure requirements. Its outlet is connected to the cartridge-type priority diverter valve's oil inlet 601, forming a closed-loop control system. The steering relief valve is a safety element that limits the maximum steering system pressure. The center unloading valve is a pressure control unit integrated into the excavation valve.

[0039] Specifically, when the steering system is inactive, the oil output from the load-sensing pump is fully supplied to the working system via a cartridge-type priority diverter valve. When the steering gear begins operating, the cartridge-type priority diverter valve's feedback port 604 connects to the steering gear's oil inlet 601. The load pressure signal is transmitted through a fixed damping orifice to the spring chamber 4 of the diverter valve core 501, pushing the valve core to change the throttle groove opening, prioritizing the pump's oil output to the steering system. The steering relief valve opens to relieve pressure when the steering system pressure exceeds a set value. The Ls relief valve regulates the control pressure of the load-sensing pump. The center unloading valve connects the working oil line to the tank when the digging valve is in the center position, achieving low-pressure unloading. The cartridge-type priority diverter valve and the center unloading valve share the same socket structure, allowing the multi-way valve to be manufactured using a standardized valve sleeve 101. Simply replacing the internal valve core assembly allows for different functions.

[0040] Compared with existing technologies, traditional solutions require independent priority valves and external piping to connect the steering system and working system, resulting in complex piping layouts and large space requirements. This solution integrates the priority diverter valve within the loading valve, eliminating external connecting piping. A standardized socket design allows the priority diverter valve and the center unloading valve to share the valve sleeve 101 structure, reducing the number of multi-way valve manufacturing steps. Utilizing closed-loop control with a load-sensing pump and a cartridge valve core, this solution achieves on-demand flow distribution while ensuring steering priority.

[0041] The above technical solution can effectively reduce the number of pipe connection points and the processing steps of the multi-way valve in the hydraulic system, and improve the utilization rate of the raw materials of the valve body 6. The plug-in structure makes the replacement and maintenance of the priority diverter valve more convenient.

[0042] In some embodiments, the socket of the center unloading valve is identical to the socket of the cartridge-type priority diverter valve. The socket serves as an assembly interface on the hydraulic valve body 6 for mounting the cartridge valve assembly. Specifically, this can be achieved by employing a uniform inner diameter, identical sealing groove layout, and identical positioning datums. This structure eliminates the need to adjust processing parameters when installing valve bodies 6 with different functions.

[0043] Specifically, during the casting phase of the hydraulic valve body 6, the same set of molds is used to machine the sockets for the center unloader valve and the priority diverter valve, ensuring that both have identical mounting cavity depth, sealing groove position, and positioning step height. When assembling the center unloader valve or the priority diverter valve, the operator uses the same press-fitting tool to press the valve assembly into the socket. The sealing ring installation position and the outer diameter of the valve sleeve 101 of both valve bodies 6 match the same socket inner wall structure. During maintenance and replacement, disassembly tools and installation fixtures are fully interchangeable, eliminating the need for specialized equipment for different valve body 6 types.

[0044] Through the above technical solution, the present application realizes the standardization of the socket processing process of the hydraulic valve body 6, which significantly reduces the socket processing time of the center unloading valve and the priority diverter valve, and significantly improves the manufacturing efficiency and maintenance convenience of the hydraulic system.

[0045] Other structures and operations of the cartridge priority diverter valve and the hydraulic system according to the embodiment of the present invention are well known to those skilled in the art and will not be described in detail here.

[0046] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0047] While 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 invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A cartridge-type priority diverter valve, characterized in that: include: Valve body, valve sleeve assembly, plug assembly, spring seat, spring and diverter valve core assembly; The valve body is provided with an oil inlet, a first working oil port, a second working oil port and a feedback oil port; The diverter valve core assembly is installed inside the valve sleeve; The valve sleeve assembly comprises: a valve sleeve, on which six first radial holes, six second radial holes, a first fixed damping hole and a second fixed damping hole are provided; The diverter valve core assembly includes: a diverter valve core and a variable damping. Four axial throttling grooves are arranged on the circumference of the diverter valve core. A guide annular groove is arranged on the rear circumferential surface of the diverter valve core. A radial through hole is arranged on the guide annular groove. An axial hole is opened on the rear end surface of the diverter valve core. The rear end of the diverter valve core and the inner side wall of the valve body form a pilot control chamber.

2. The cartridge-type priority diverter valve according to claim 1, characterized in that: The valve sleeve assembly also includes a first O-ring, a second O-ring, a third O-ring, a first retaining ring, a second retaining ring and a Gley ring; the valve sleeve surface is axially spaced apart with a first annular groove, a second annular groove, a third annular groove, a fourth annular groove, a fifth annular groove and a sixth annular groove, the Gley ring is installed on the first annular groove, the second O-ring and the first retaining ring are both installed on the second annular groove, a third radial hole is opened on the fifth annular groove, and the third O-ring and the second retaining ring are both installed on the sixth annular groove.

3. The cartridge-type priority diverter valve according to claim 1, characterized in that: The rear portion of the diverter valve core is provided with a conical surface.

4. The cartridge-type priority diverter valve according to claim 1, characterized in that: The plug assembly includes a screw plug and a fourth O-ring. A sealing annular groove is provided on the screw plug, and the fourth O-ring is installed on the sealing annular groove.

5. The cartridge-type priority diverter valve according to claim 4, characterized in that: The spring seat is installed on the screw plug, and the spring is installed between the spring seat and the diverter valve core.

6. A hydraulic system for a backhoe loader, characterized in that: It comprises the plug-in priority diverter valve, load-sensing pump, excavation valve, loading valve, steering gear, steering cylinder and oil tank described in any one of claims 1 to 5; the loading valve is integrated with the plug-in priority diverter valve, steering relief valve, shuttle valve, Ls relief valve and constant flow valve; the excavation valve is integrated with a mid-position unloading valve.

7. The hydraulic system for a backhoe loader according to claim 6, characterized in that: The insertion hole of the mid-position unloading valve is the same as the insertion hole of the cartridge-type priority diverter valve.

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