Double liquid control non-return valve

Abstract

The utility model discloses a double liquid control check valve, integrate two sets of check valve function unit in same valve body, form first, second valve element assembly. The assembly adopts "operating screw head / screw sleeve - connecting sleeve - piston sleeve" multilayer thread suit, built-in top rod - valve element - double spring mechanism, realize positive free flow and liquid control reverse opening, and the second valve element assembly adds rotatable adjusting screw head, can carry out on -the -spot fine adjustment opening stroke, compensate wear and tear and working condition difference. The screw sleeve head is polygonal, can be quickly disassembled and assembled with standard wrench, is locked with bolt between each section, prevents loosening, and the piston sleeve sets the limiting step, and once rotates into the positioning. Compared with the traditional double valve parallel connection scheme, the volume is reduced by more than 30%, the pipeline is short, and the leakage point is few, the module is independent, can be adjusted under pressure, and the maintenance is in minute level, is applicable to the hydraulic system of engineering machinery, crane and other high reliable pressure maintaining locking.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic control technology, specifically to a double hydraulic control check valve. Background Technology

[0002] Hydraulic check valves are fundamental core components in hydraulic systems. They reliably shut off the oil circuit and can be reversed by pilot control pressure. They are widely used in actuators requiring long-term pressure holding and locking, such as outriggers in construction machinery and luffing cylinders in cranes. In these applications with extremely high safety requirements, dual hydraulic check valves are typically used to form a redundant locking system (i.e., double interlocking) to significantly improve system reliability.

[0003] Currently, common dual-pivot hydraulic check valves are mostly implemented by installing two independent check valves in parallel or by integrating them into a valve block. However, this structure has disadvantages such as large overall size and complex connection pipelines. In addition, some integrated dual-pivot valves, although integrating two valve cores into a single valve body, often have a simple symmetrical structure in their control components. This symmetrical design makes it difficult to independently adjust the opening performance of each valve according to the difference in actual working pressure and flow rate at the two ports, which may lead to asynchronous operation of the two valves and affect system stability.

[0004] On the other hand, existing hydraulically controlled check valves mostly use a floating control rod design, which is prone to wear under long-term frequent operation, affecting the accuracy of valve core opening and sealing. When internal leakage occurs due to wear at the valve port, there is often a lack of effective on-site adjustment methods, requiring the replacement of the entire valve core assembly, which is inconvenient and costly to maintain. Therefore, there is an urgent need in this field for a new type of double hydraulically controlled check valve, which should have a compact structure, high reliability, and the ability to independently adjust the two valves to meet the high performance and high reliability requirements of modern hydraulic systems. Utility Model Content

[0005] To address the shortcomings in the prior art, this utility model provides a dual-stage hydraulic control check valve.

[0006] The technical solution adopted by this utility model is: a double hydraulic control check valve, including a valve body and a first valve core assembly and a second valve core assembly disposed on the valve body. The valve body is provided with a first valve hole and a second valve hole for installing the first valve core assembly and the second valve core assembly. The first valve core assembly includes an operating screw head threaded to the first valve hole, a first connecting sleeve connected to the operating screw head, a first piston sleeve connected to the first connecting sleeve, a first push rod abutting against the bottom wall of the mounting cavity of the operating screw head, a first valve core slidably disposed in the first sliding cavity of the first piston sleeve, a first spring sleeved on the first push rod, and a second spring disposed in the first sliding cavity. The first push rod passes through the first connecting sleeve and abuts against the first valve core. The second valve core assembly includes an operating sleeve threadedly connected to the second valve hole, a second connecting sleeve connected to the operating sleeve, a second piston sleeve connected to the second connecting sleeve, a screw head threadedly connected to the inner hole of the operating sleeve, a second push rod movably disposed in the inner hole and abutting against the screw head, a second valve core slidably disposed in the second sliding cavity of the second piston sleeve, a third spring fitted on the second push rod, and a fourth spring disposed in the second sliding cavity. The first push rod passes through the first connecting sleeve and abuts against the first valve core.

[0007] Furthermore, an internal hexagonal hole is provided on the end of the screw head.

[0008] Furthermore, the end of the operating screw sleeve has an equilateral polygonal structure.

[0009] Furthermore, the operating screw head is fixedly connected to the first connecting sleeve, the first connecting sleeve to the first piston sleeve, the operating screw sleeve to the second connecting sleeve, and the second connecting sleeve to the second piston sleeve by bolts.

[0010] Furthermore, both the first piston sleeve and the second piston sleeve are provided with limit steps at their tops.

[0011] The beneficial effects of this utility model are: 1. Highly compact structure and integrated design: By integrating the first and second valve core assemblies into a single valve body and employing a multi-layered sleeve connection structure including the operating screw, connecting sleeve, and piston sleeve, the internal space layout is greatly optimized. Compared to the traditional scheme of two independent valves connected in parallel or stacked, this reduces the overall volume and weight of the valve body, facilitating installation and deployment in space-constrained hydraulic systems, and aligning with the development trend of compact and integrated hydraulic systems.

[0012] 2. Dual-valve control allows for independent fine-tuning, offering strong adaptability and reliability: The first valve core assembly uses a push rod that abuts against a fixed operating screw, resulting in a simple and reliable structure. The second valve core assembly, however, positions the second push rod via a threaded adjustable screw. This key difference allows operators to easily and independently fine-tune the relative position of the second push rod by rotating the screw, thereby precisely controlling the opening stroke or preload of the second valve core. This design effectively compensates for manufacturing tolerances and wear caused by long-term operation, ensuring that the dual valves maintain good and synchronized opening and closing characteristics in oil circuits with different pressure and flow characteristics, greatly enhancing the system's adaptability and overall reliability under various operating conditions.

[0013] 3. Modular design for easy machining, assembly, and maintenance: The valve core assembly adopts a modular design, allowing each part (such as the operating screw / sleeve, connecting sleeve, piston sleeve, valve core, etc.) to be machined separately and then assembled into an independent valve core module, which is then screwed into the valve bore of the valve body. This design not only reduces the machining difficulty of individual parts but also makes the assembly process simpler and more standardized. When maintenance is required, the entire valve core assembly can be easily removed from the valve body for inspection, replacement, or adjustment, greatly simplifying the maintenance process and reducing subsequent maintenance costs.

[0014] In addition to the objectives, features and advantages described above, this utility model has other objectives, features and advantages.

[0015] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] Figure 2 This is a cross-sectional schematic diagram of the present invention.

[0018] Figure 3 This is a schematic diagram of the structure of the first valve core assembly and the second valve core assembly.

[0019] Figure 1-3 In the middle: 1. Valve body; 2. First valve core assembly; 3. Second valve core assembly; 4. First valve hole; 5. Second valve hole; 6. Operating screw head; 7. First connecting sleeve; 8. First piston sleeve; 9. Mounting cavity; 10. First push rod; 11. First sliding cavity; 12. First valve core; 13. First spring; 14. Second spring; 15. Operating screw sleeve; 16. Second connecting sleeve; 17. Second piston sleeve; 18. Inner hole; 19. Screw head; 20. Second push rod; 21. Second sliding cavity; 22. Second valve core; 23. Third spring; 24. Fourth spring; 25. Internal hexagonal hole; 26. Bolt; 27. Limiting step. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0022] This utility model provides a dual-stage hydraulic control check valve.

[0023] In this embodiment, refer to Figure 1-3 The dual-stage hydraulic check valve includes a valve body 1 and a first valve core assembly 2 and a second valve core assembly 3 disposed on the valve body 1. The valve body is provided with a first valve hole 4 and a second valve hole 5 for mounting the first valve core assembly and the second valve core assembly. The first valve core assembly includes an operating screw head 6 threadedly connected to the first valve hole, a first connecting sleeve 7 connected to the operating screw head 6, a first piston sleeve 8 connected to the first connecting sleeve 7, a first push rod 10 abutting against the bottom wall of the mounting cavity 9 of the operating screw head, a first valve core 11 slidably disposed in the first sliding cavity of the first piston sleeve, a first spring 12 fitted on the first push rod, and a second spring 14 disposed in the first sliding cavity 13. The first push rod passes through the first connecting sleeve and abuts against the first valve core. The second valve core assembly includes an operating sleeve 15 threadedly connected to the second valve hole, a second connecting sleeve 16 connected to the operating sleeve 15, a second piston sleeve 17 connected to the second connecting sleeve 16, a screw head 19 threadedly connected to the inner hole 18 of the operating sleeve 16, a second push rod 20 movably disposed in the inner hole 18 and abutting against the screw head, a second valve core 22 slidably disposed in the second sliding cavity 21 of the second piston sleeve, a third spring 23 fitted on the second push rod, and a fourth spring 24 disposed in the second sliding cavity. The first push rod passes through the first connecting sleeve and abuts against the first valve core.

[0024] In the above technical solution, two complete hydraulic control check valve functional units are integrated into the same valve body "back to back" to form a double structure; the first valve port and the second valve port are arranged in parallel and share the valve body flow channel.

[0025] The push rod, valve core, and double springs combine to create a "hydraulic pressure relief + mechanical forced opening" action. a) When the pressure at port A is higher than that at port B and exceeds the spring force, the valve core automatically opens, allowing free flow in the forward direction; b) When reverse flow is required, pressure is supplied to the X control port, the piston sleeve cavity is forced to push the push rod, and the valve core is forcibly opened to realize the "reverse flow" function of the hydraulic control check valve; c) The first spring provides the initial sealing force, and the second (fourth) spring helps the valve core to quickly reset and ensure the sealing pressure ratio after the control chamber is depressurized.

[0026] Dual-unit design: Reduces volume by 30-40% compared to two independent one-way valves, shortens pipelines, and reduces leakage points.

[0027] Threaded segment assembly: The valve body can be unscrewed with a regular wrench without removing it from the equipment on site, allowing for the replacement of the valve core, spring, and sealing ring. Maintenance time is reduced from hours to minutes.

[0028] The push rod-double spring combination ensures both zero leakage (high initial sealing force) and low control pressure (large control piston area), resulting in less reversing impact and reduced noise.

[0029] Symmetrical design + interchangeable parts: 80% of the parts in the first and second components are interchangeable, reducing the variety of inventory by half.

[0030] Specifically, the end of the screw head is provided with an internal hexagonal hole 25.

[0031] In this embodiment, an internal hexagonal hole is machined on the end face of the screw head, which is equivalent to integrating the "adjusting screw" function into the screw head itself; the screw head can be rotated with an internal hexagonal wrench to change its axial position in the operating sleeve.

[0032] Specifically, the end of the operating screw sleeve has an equilateral polygonal structure.

[0033] In this embodiment, the head of the operating screw sleeve is made into an equilateral polygon to facilitate manual operation.

[0034] Specifically, the operating screw head is fixedly connected to the first connecting sleeve, the first connecting sleeve to the first piston sleeve, the operating screw sleeve to the second connecting sleeve, and the second connecting sleeve to the second piston sleeve by bolts 26.

[0035] In this embodiment, the components are connected by bolts, which facilitates disassembly and assembly, and also allows for the individual replacement of parts.

[0036] Specifically, both the first piston sleeve and the top of the second piston sleeve are provided with a limiting step 27.

[0037] A limiting step (shoulder) is machined on the top of the outer circle of the first and second piston sleeves. When the assembly is screwed into the valve body, the step fits into the countersunk hole at the valve orifice to form an axial positioning surface.

[0038] Attention all technical personnel: Although this utility model has been described according to the specific embodiments above, the concept of this utility model is not limited to this utility model. Any modification that utilizes the concept of this utility model will be included within the scope of protection of this patent right.

Claims

1. A dual-stage hydraulic control check valve, comprising a valve body and a first valve core assembly and a second valve core assembly disposed on the valve body, wherein the valve body is provided with a first valve hole and a second valve hole for mounting the first valve core assembly and the second valve core assembly, characterized in that: The first valve core assembly includes an operating screw head threadedly connected to a first valve hole, a first connecting sleeve connected to the operating screw head, a first piston sleeve connected to the first connecting sleeve, a first push rod abutting against the bottom wall of the mounting cavity of the operating screw head, a first valve core slidably disposed in the first sliding cavity of the first piston sleeve, a first spring fitted on the first push rod, and a second spring disposed in the first sliding cavity. The first push rod passes through the first connecting sleeve and abuts against the first valve core. The second valve core assembly includes an operating sleeve threadedly connected to the second valve hole, a second connecting sleeve connected to the operating sleeve, a second piston sleeve connected to the second connecting sleeve, a screw head threadedly connected to the inner hole of the operating sleeve, a second push rod movably disposed in the inner hole and abutting against the screw head, a second valve core slidably disposed in the second sliding cavity of the second piston sleeve, a third spring fitted on the second push rod, and a fourth spring disposed in the second sliding cavity. The first push rod passes through the first connecting sleeve and abuts against the first valve core.

2. The double pilot operated check valve of claim 1, wherein: The screw head has an internal hexagonal hole at its end.

3. The double pilot operated check valve of claim 1, wherein: The end of the operating screw sleeve has an equilateral polygonal structure.

4. The dual hydraulically controlled check valve according to claim 1, characterized in that: The operating screw head is fixedly connected to the first connecting sleeve, the first connecting sleeve to the first piston sleeve, the operating screw sleeve to the second connecting sleeve, and the second connecting sleeve to the second piston sleeve by bolts.

5. The dual hydraulically controlled check valve according to claim 1, characterized in that: Both the first piston sleeve and the second piston sleeve have limit steps at their tops.

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