Dual check valve
By using an integrated intermediate body and an additional check valve structure, the problem of insufficient sealing performance of dual check valves under high pressure is solved, simplifying the sealing design, improving sealing reliability and production efficiency, and reducing vibration noise and leakage risks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NINGBO NUCLEAR FLUID MACHINERY CO LTD
- Filing Date
- 2025-08-25
- Publication Date
- 2026-06-23
AI Technical Summary
Existing double check valves have insufficient sealing performance under high pressure, resulting in insufficient intake and delivery. In addition, the sealing surfaces are numerous and complex, which increases the difficulty of processing and the probability of failure.
By using an integrated molding intermediate, the connecting part between two one-way valves is integrated into a single component, reducing the sealing surface and adding a one-way valve structure to ensure the valve ball sits. The sealing design is simplified through integral casting or precision machining, reducing vibration noise and leakage risks.
It simplifies the sealing design, reduces the number of sealing-related parts, improves sealing reliability and production efficiency, reduces vibration and noise under fluid impact, improves sealing performance by 50%, reduces potential leakage points, and simplifies the assembly process.
Smart Images
Figure CN224397220U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of double one-way valve technology, and particularly to a double one-way valve. Background Technology
[0002] When a metering pump is working, it generates pressure on the pump head through a diaphragm, which drives the valve ball inside the check valve on the metering pump to move up and down, creating a pressure difference for liquid intake and delivery. However, under high pressure (such as 200 Bar), the pressure generated is too great, and the valve ball cannot sit properly on the valve seat due to the pressure difference, resulting in insufficient sealing and internal leakage problems such as insufficient intake and delivery.
[0003] In existing technologies, the conventional construction of dual check valves generally adopts a "dual-unit splicing" model—two check valves with identical structures are joined end-to-end to form an integral passage. Although this design can achieve basic functions with the help of standardized check valve components, the splicing part requires additional sealing accessories (such as sealing rings, glands, etc.) to complete the connection and sealing.
[0004] From a practical application perspective, this splicing structure has significant limitations: the mating surfaces of the two one-way valves form two independent sealing interfaces, each requiring precise control of fit tolerances, surface finish, and seal compression. This not only places higher demands on machining accuracy (e.g., the flatness of the mating surfaces must be controlled within 0.02 mm / m), but also increases the risk of seal failure—wear, aging, or assembly deviations at any sealing surface can lead to media leakage, especially in high-pressure or corrosive media environments, where the probability of failure increases significantly. Furthermore, the additional sealing components complicate the overall assembly process, and consequently increase the disassembly and replacement costs during later maintenance.
[0005] Therefore, we propose a dual check valve. Utility Model Content
[0006] The main objective of this invention is to provide a dual one-way valve, which effectively solves the problem that existing single- or double-body valves require additional sealing components (such as sealing rings, glands, etc.) to complete the connection and sealing at the splicing point. The mating surfaces of the two one-way valves form two independent sealing interfaces, each requiring precise control of fit tolerances, surface finish, and seal compression. This not only places higher demands on machining accuracy but also increases the risk of seal failure. Wear, aging, or assembly deviations on any sealing surface can lead to media leakage, especially in high-pressure or corrosive media environments, where the probability of failure increases significantly.
[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0008] A dual one-way valve includes a valve seat, a second body disposed at the middle of the upper end of the valve seat, an intermediate body disposed at the upper end of the valve seat, the intermediate body being an integrally formed structure, a second mounting sleeve disposed inside the lower end of the intermediate body, the second mounting sleeve being sleeved and mounted on the second body, a first body disposed at the middle of the upper end of the intermediate body, a valve cap disposed at the upper end of the intermediate body, a first mounting sleeve disposed inside the lower end of the valve cap, the first mounting sleeve being sleeved and mounted on the first body;
[0009] The second body has a third through hole inside, the intermediate body has a first valve chamber inside, the valve cap has a second valve chamber inside, the first valve chamber has a first valve ball inside, and the second valve chamber has a second valve ball inside.
[0010] Furthermore, gasket grooves are provided on the upper and lower end faces of the valve seat, the upper end face of the intermediate body, and the upper end face of the valve cap, and gaskets are provided inside the four gasket grooves.
[0011] Furthermore, a third body is provided at the upper end of the valve cap, and a first through hole is provided inside the third body, which is connected to the second valve cavity. A second through hole is provided inside the first body, which is connected to the first valve cavity.
[0012] Furthermore, the upper cross-sections of both the first valve chamber and the second valve chamber are circular, and the sidewall of the first valve chamber is provided with a plurality of first side supports at equal intervals, and the sidewall of the second valve chamber is provided with a plurality of second side supports at equal intervals.
[0013] Furthermore, the inner diameter of the third through hole is smaller than the diameter of the first valve ball, and the inner diameter of the second through hole is smaller than the diameter of the second valve ball.
[0014] Compared with the prior art, the present invention has the following beneficial effects:
[0015] This invention utilizes an integrated intermediate body, employing integral casting or precision machining processes, to integrate the connecting parts of two one-way valves that originally required splicing into a single component. Without significantly increasing the overall structural complexity, it directly eliminates the two splicing sealing surfaces. This improvement not only simplifies the sealing design logic and reduces sealing-related components by at least 30%, but also enhances overall rigidity through the integrated structure, reducing vibration and noise under fluid impact.
[0016] More importantly, the reduction in the number of sealing surfaces significantly reduces potential leakage points. Under the same machining precision, sealing reliability can be improved by about 50%, while the assembly process is reduced by 2 steps, which significantly improves production efficiency.
[0017] This utility model of a double check valve adds an extra check valve structure to the basic single check valve. When the pressure is too high and the valve ball cannot sit, the addition of an extra check valve structure ensures that even if the valve ball of the first-stage check valve cannot sit, the valve ball of the second-stage check valve can sit on the valve seat due to the buffer provided by the first-stage check valve. This ensures the sealing of the check valve and solves the internal leakage problem.
[0018] The parts of the device not covered herein are the same as or can be implemented using existing technologies. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of the dual one-way valve of this utility model.
[0020] Figure 2 This is an exploded view of the dual one-way valve of this utility model.
[0021] Figure 3 This is a cross-sectional view of the dual one-way valve of this utility model.
[0022] Figure 4 This is a partial sectional view of the dual one-way valve of this utility model.
[0023] Figure 5 This utility model is a double check valve. Figure 1 Cross-sectional view of AA.
[0024] In the diagram: 1. Valve seat; 2. Intermediate body; 3. Valve cap; 4. Washer; 5. First valve ball; 6. Second valve ball; 7. First valve chamber; 8. Second valve chamber; 9. First side support; 10. Second side support; 11. First mounting sleeve; 12. Second mounting sleeve; 13. First platform; 14. Second platform; 15. First through hole; 16. Second through hole; 17. Third through hole. Detailed Implementation
[0025] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.
[0026] like Figure 1-5 As shown, a double one-way valve includes a valve seat 1, a second body 14 disposed at the middle of the upper end of the valve seat 1, an intermediate body 2 disposed at the upper end of the valve seat 1, the intermediate body 2 being an integrally formed structure, a second mounting sleeve 12 being provided inside the lower end of the intermediate body 2, and the second mounting sleeve 12 being sleeved and mounted on the second body 14, a first body 13 disposed at the middle of the upper end of the intermediate body 2, a valve cap 3 disposed at the upper end of the intermediate body 2, a first mounting sleeve 11 being provided inside the lower end of the valve cap 3, and the first mounting sleeve 11 being sleeved and mounted on the first body 13;
[0027] The second body 14 has a third through hole 17 inside, the intermediate body 2 has a first valve chamber 7 inside, the valve cap 3 has a second valve chamber 8 inside, the first valve chamber 7 has a first valve ball 5 inside, and the second valve chamber 8 has a second valve ball 6 inside.
[0028] Specifically, the valve cap 3, the second valve ball 6, and the intermediate body 2 form a first-stage check valve mechanism, and the intermediate body 2, the first valve ball 5, and the valve seat 1 form a second-stage check valve mechanism. Due to the setting of the intermediate body 2, an additional check valve structure is added on the basis of a single check valve. In the case of excessive pressure and the valve ball failing to sit, because of the additional check valve structure, even if the valve ball of the first-stage check valve cannot sit, the valve ball of the second-stage check valve can sit on the valve seat 1 because of the buffer provided by the first-stage check valve, thereby ensuring the sealing of the check valve and solving the internal leakage problem.
[0029] As a specific embodiment of this utility model, the upper and lower end faces of the valve seat 1, the upper end face of the intermediate body 2 and the upper end face of the valve cap 3 are all provided with washer grooves, and washer 4 is provided inside each of the four washer grooves.
[0030] It should be noted that the use of four gaskets (4) can effectively solve the sealing problem and ensure the sealing operation of the entire double check valve.
[0031] As a specific embodiment of this utility model, the upper end of the valve cap 3 is provided with a third platform, the interior of the third platform is provided with a first through hole 15, and the first through hole 15 is connected to the second valve cavity 8. The interior of the first platform 13 is provided with a second through hole 16, and the second through hole 16 is connected to the first valve cavity 7.
[0032] As a specific embodiment of this utility model, the upper cross-sections of the first valve cavity 7 and the second valve cavity 8 are both circular. The side wall of the first valve cavity 7 is provided with a plurality of first side supports 9 at equal intervals, and the side wall of the second valve cavity 8 is provided with a plurality of second side supports 10 at equal intervals.
[0033] In a specific embodiment of this utility model, the inner diameter of the third through hole 17 is smaller than the diameter of the first valve ball 5, and the inner diameter of the second through hole 16 is smaller than the diameter of the second valve ball 6.
[0034] The double check valve is based on the single check valve, with an additional check valve structure. In the event of excessive pressure and the valve ball failing to seat, the additional check valve structure ensures that even if the valve ball of the first-stage check valve fails to seat, the valve ball of the second-stage check valve can seat on the valve seat 1 due to the buffer provided by the first-stage check valve. This guarantees the sealing of the check valve and solves the internal leakage problem.
[0035] Working principle: This utility model is a double one-way valve. During installation, firstly, the gasket 4 is placed in the gasket groove of the valve seat 1, and the first valve ball 5 is placed in the first valve cavity 7. Then, the second mounting sleeve 12 of the intermediate body 2 is fitted onto the second platform 14 of the valve seat 1. Next, the second gasket 4 is placed in the gasket groove on the intermediate body 2, and the second valve ball 6 is placed into the second valve cavity 8. Finally, the first mounting sleeve 11 of the valve cap 3 is fitted onto the first platform 13 of the intermediate body 2, thus completing the assembly of the entire double one-way valve. This utility model, by using an integrated molded intermediate body 2 and through integral casting or precision machining, integrates the intermediate connecting parts of the two one-way valves that originally needed to be spliced into a single component. Without significantly increasing the overall structural complexity, it directly eliminates the two splicing sealing surfaces. This improvement not only simplifies the sealing design logic but also reduces costs by at least 30%. The sealing-related components can also improve overall rigidity through an integrated structure, reducing vibration and noise under fluid impact. During operation, even if the second valve ball 6 of the first-stage check valve mechanism formed between the valve cap 3, the second valve ball 6, and the intermediate body 2 cannot sit down, the first valve ball 5 of the second-stage check valve mechanism formed between the intermediate body 2, the first valve ball 5, and the valve seat 1 can sit on the valve seat 1 because the first-stage check valve has provided buffering. This ensures the sealing performance of the check valve, solves the internal leakage problem, and is quite practical.
[0036] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A double check valve, including a valve seat (1), characterized in that: The valve seat (1) has a second body (14) in the middle of its upper end, and an intermediate body (2) in the upper end of the valve seat (1). The intermediate body (2) is an integrally formed structure. The lower end of the intermediate body (2) has a second mounting sleeve (12) inside, and the second mounting sleeve (12) is fitted onto the second body (14). The intermediate body (2) has a first body (13) in the middle of its upper end, and a valve cap (3) in the upper end of the intermediate body (2). The lower end of the valve cap (3) has a first mounting sleeve (11) inside, and the first mounting sleeve (11) is fitted onto the first body (13). The second body (14) has a third through hole (17) inside, the intermediate body (2) has a first valve chamber (7) inside, the valve cap (3) has a second valve chamber (8) inside, the first valve chamber (7) has a first valve ball (5) inside, and the second valve chamber (8) has a second valve ball (6) inside.
2. The dual check valve according to claim 1, characterized in that: The upper and lower end faces of the valve seat (1), the upper end face of the intermediate body (2) and the upper end face of the valve cap (3) are all provided with gasket grooves, and gaskets (4) are provided inside the four gasket grooves.
3. The dual check valve according to claim 1, characterized in that: The upper end of the valve cap (3) is provided with a third body, and the interior of the third body is provided with a first through hole (15), which is connected to the second valve cavity (8). The interior of the first body (13) is provided with a second through hole (16), which is connected to the first valve cavity (7).
4. The dual check valve according to claim 1, characterized in that: The upper cross sections of the first valve chamber (7) and the second valve chamber (8) are both circular. The side wall of the first valve chamber (7) is provided with a number of first side supports (9) at equal intervals, and the side wall of the second valve chamber (8) is provided with a number of second side supports (10) at equal intervals.
5. The dual check valve according to claim 3, characterized in that: The inner diameter of the third through hole (17) is smaller than the diameter of the first valve ball (5), and the inner diameter of the second through hole (16) is smaller than the diameter of the second valve ball (6).