One-way valve and plunger pump

Abstract

The utility model provides a one-way valve which comprises a valve seat, an oil inlet cavity and an oil outlet cavity are arranged in the valve seat, a first oil inlet of the oil inlet cavity is communicated with an oil inlet pipeline, a second oil outlet of the oil outlet cavity is communicated with an oil outlet pipeline, and a first oil outlet of the oil inlet cavity and a second oil inlet of the oil outlet cavity are communicated with a plunger cavity. A plunger is mounted in the plunger cavity in a sliding manner; a first sealing element is arranged in the oil inlet cavity, a second sealing element is arranged in the oil outlet cavity, and the first sealing element and the second sealing element are configured as follows: the first sealing element and the second sealing element are in a normally closed state, and when the negative pressure in the plunger cavity exceeds a threshold value, the first sealing element is opened; when the positive pressure in the plunger cavity exceeds a threshold value, the second sealing element is opened. The oil inlet cavity and the oil outlet cavity are formed in the valve seat, and the sealing elements are arranged in the oil inlet cavity and the oil outlet cavity, so that the bidirectional circulation requirement of a specific oil pump can be met, and the size of the oil pump is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of check valves, in particular to a check valve and a plunger pump. Background Art

[0002] The structure of a traditional check valve usually consists of a valve body, a valve seat, a valve flap, a spring, etc. These components work together to ensure that fluid can only pass through in one direction, and cannot meet the two-way flow requirements of some specific oil pumps (such as plunger pumps, etc.). During the operation of the plunger pump, in order to ensure the smooth progress of the oil suction action and the oil discharge action, generally two check valves are required, which increases the volume of the oil pump and is not conducive to the miniaturization design of the equipment. Summary of the Utility Model

[0003] The utility model provides a check valve and a plunger pump, which solve the problems that the traditional check valve in the prior art cannot meet the two-way flow requirements of specific oil pumps, etc.

[0004] The technical solution of the utility model is realized as follows:

[0005] In a first aspect of the utility model, a check valve is provided, which includes a valve seat. An oil inlet cavity and an oil outlet cavity are arranged in the valve seat. A first oil inlet of the oil inlet cavity is communicated with an oil inlet pipeline, a second oil outlet of the oil outlet cavity is communicated with an oil outlet pipeline, a first oil outlet of the oil inlet cavity and a second oil inlet of the oil outlet cavity are communicated with a plunger cavity, and a plunger is slidably installed in the plunger cavity; a first sealing element is arranged in the oil inlet cavity, and a second sealing element is arranged in the oil outlet cavity. The first sealing element and the second sealing element are configured as follows:

[0006] The first sealing element and the second sealing element are in a normally closed state. When the negative pressure in the plunger cavity exceeds a threshold value, the first sealing element opens; when the positive pressure in the plunger cavity exceeds a threshold value, the second sealing element opens.

[0007] By arranging an oil inlet cavity and an oil outlet cavity in the valve seat, and respectively arranging a first sealing element and a second sealing element in the oil inlet cavity and the oil outlet cavity, driving the plunger to reciprocate linearly in the plunger cavity, generating positive pressure and negative pressure cyclically in the plunger cavity, sucking the fluid in the oil inlet pipeline into the plunger cavity through the first sealing element opened by the negative pressure, and then pumping the fluid in the plunger cavity into the oil outlet pipeline through the second sealing element opened by the negative pressure, the two-way flow requirements of specific oil pumps can be met, thereby reducing the volume of the oil pump.

[0008] Specifically, the oil inlet chamber includes a first chamber and a second chamber that are connected. The first oil inlet is opened at the part where the first chamber is connected to the oil inlet pipeline, and the second oil inlet is opened at the part where the second chamber is connected to the plunger chamber. The first sealing element includes a first sealing steel ball, and the outer diameter of the first sealing steel ball is greater than the inner diameter of the first chamber and less than the inner diameter of the second chamber. When the plunger is driven to slide in a direction away from the valve seat, a negative pressure is formed in the plunger chamber. When the negative pressure exceeds the threshold value, the second sealing steel ball leaves the communication port between the first chamber and the second chamber, and the fluid in the oil inlet pipeline is sucked into the plunger chamber from the first oil outlet through the oil inlet chamber.

[0009] Optionally, the oil inlet chamber is a conical chamber, and the small end of the oil inlet chamber is connected to the oil inlet pipeline through the first oil inlet, and the large end of the oil inlet chamber is connected to the plunger chamber through the first oil outlet. The first sealing element includes a first sealing steel ball, and the outer diameter of the first sealing steel ball is greater than the inner diameter of the small end of the oil inlet chamber and less than the inner diameter of the large end of the oil inlet chamber.

[0010] Further, a limiting block is provided at the first oil outlet of the oil inlet chamber to prevent the first sealing steel ball from coming out of the first oil outlet.

[0011] Preferably, a first spring is further provided in the oil inlet chamber. The first spring is located between the first sealing steel ball and the limiting block, further improving the sensitivity of the first sealing steel ball to reset. When the negative pressure in the plunger chamber is lower than the threshold value, the first sealing steel ball can quickly reset under the action of the first spring to seal the communication port between the first chamber and the second chamber.

[0012] Specifically, the oil outlet chamber includes a third chamber and a fourth chamber. The second oil inlet is opened at the part where the third chamber is connected to the plunger chamber, and the second oil outlet is opened at the part where the fourth chamber is connected to the oil outlet pipeline. The second sealing element includes a second sealing steel ball and a second spring. The outer diameter of the second sealing steel ball is greater than the inner diameter of the third chamber and less than the inner diameter of the fourth chamber. A limiting component is provided at the second oil outlet, and the second spring is located between the second sealing steel ball and the limiting component. When the plunger is driven to slide in a direction close to the valve seat, a positive pressure is formed in the plunger chamber. When the positive pressure exceeds the threshold value, the second spring is compressed, and the second sealing steel ball leaves the communication port between the third chamber and the fourth chamber. The fluid in the plunger chamber is pumped out from the second oil outlet through the oil outlet chamber.

[0013] Further, the limiting component is a plug. The plug is provided with a shaft hole, and the shaft hole is communicated with the second oil outlet. The second spring is located between the second sealing steel ball and the plug.

[0014] Preferably, the plug is screwed to the fourth chamber, which is convenient for adjusting the pre-tightening force of the second spring according to requirements.

[0015] Optionally, the oil outlet cavity is a conical cavity, and the large end of the oil outlet cavity is communicated with the oil outlet pipeline through a second oil outlet, and the small end of the oil outlet cavity is communicated with the plunger cavity through a second oil inlet; the second sealing element includes a second sealing steel ball and a second spring, and the outer diameter of the second sealing steel ball is greater than the inner diameter of the small end of the oil outlet cavity and less than the inner diameter of the large end of the oil outlet cavity; a limiting component is arranged at the second oil outlet, and the second spring is located between the second sealing steel ball and the limiting component.

[0016] In a second aspect of the present invention, a plunger pump is provided, which includes a driving component and the above-mentioned one-way valve. The driving component is used to drive the plunger to reciprocate linearly in the plunger cavity, so as to form a positive pressure-negative pressure-positive pressure cycle in the plunger cavity and realize continuous oil supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a schematic internal structure diagram of a one-way valve of the present invention;

[0019] Figure 2 It is a schematic oil circuit diagram of the one-way valve when the plunger pump sucks oil in the embodiment of the present invention;

[0020] Figure 3 It is a schematic oil circuit diagram of the one-way valve when the plunger pump discharges oil in the embodiment of the present invention;

[0021] In the figure: 1, valve seat; 2, first oil inlet; 3, first oil outlet; 4, second oil inlet; 5, second oil outlet; 6, plunger cavity; 7, plunger; 8, first cavity; 9, second cavity; 10, first sealing steel ball; 11, limiting block; 12, third cavity; 13, fourth cavity; 14, second sealing steel ball; 15, second spring; 16, plug; 17, shaft hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0023] Refer to Figures 1 to 3, in the first aspect of the embodiment of the present utility model, a one-way valve is provided, which includes a valve seat 1. An oil inlet cavity and an oil outlet cavity are arranged in the valve seat 1. The first oil inlet 2 of the oil inlet cavity is communicated with an oil inlet pipeline, the second oil outlet 5 of the oil outlet cavity is communicated with an oil outlet pipeline, the first oil outlet 3 of the oil inlet cavity and the second oil inlet 4 of the oil outlet cavity are communicated with a plunger cavity 6, and a plunger 7 is slidably installed in the plunger cavity 6; a first sealing element is arranged in the oil inlet cavity, and a second sealing element is arranged in the oil outlet cavity. The first sealing element and the second sealing element are configured as:

[0024] The first sealing element and the second sealing element are in a normally closed state. When the negative pressure in the plunger cavity 6 exceeds the threshold value, the first sealing element opens; when the positive pressure in the plunger cavity 6 exceeds the threshold value, the second sealing element opens.

[0025] In the present utility model, by arranging an oil inlet cavity and an oil outlet cavity in the valve seat 1, and respectively arranging a first sealing element and a second sealing element in the oil inlet cavity and the oil outlet cavity, by driving the plunger 7 to reciprocate linearly in the plunger cavity 6, positive pressure and negative pressure are cyclically generated in the plunger cavity 6. The first sealing element is opened by the negative pressure to suck the fluid in the oil inlet pipeline into the plunger cavity 6 through the oil inlet cavity, and then the second sealing element is opened by the negative pressure to pump the fluid in the plunger cavity 6 out to the oil outlet pipeline through the oil outlet cavity, which can meet the bidirectional flow requirements of a specific oil pump, thereby reducing the volume of the oil pump.

[0026] Specifically, the oil inlet cavity includes a first cavity 8 and a second cavity 9 that are communicated. The first oil inlet 2 is opened at the part where the first cavity 8 is communicated with the oil inlet pipeline, and the second oil inlet 4 is opened at the part where the second cavity 9 is communicated with the plunger cavity 6; the first sealing element includes a first sealing steel ball 10, and the outer diameter of the first sealing steel ball 10 is greater than the inner diameter of the first cavity 8 and less than the inner diameter of the second cavity 9. When the plunger 7 is driven to slide in a direction away from the valve seat 1, a negative pressure is formed in the plunger cavity 6. When the negative pressure exceeds the threshold value, the second sealing steel ball 14 leaves the communication port between the first cavity 8 and the second cavity 9, and the fluid in the oil inlet pipeline is sucked into the plunger cavity 6 from the first oil outlet 3 through the oil inlet cavity.

[0027] Optionally, the oil inlet cavity can also be designed as a tapered cavity, and the small end of the oil inlet cavity is communicated with the oil inlet pipeline through the first oil inlet 2, and the large end of the oil inlet cavity is communicated with the plunger cavity 6 through the first oil outlet 3; the first sealing element includes a first sealing steel ball 10, and the outer diameter of the first sealing steel ball 10 is greater than the inner diameter of the small end of the oil inlet cavity and less than the inner diameter of the large end of the oil inlet cavity.

[0028] Furthermore, a limiting block 11 is arranged at the first oil outlet 3 of the oil inlet cavity to prevent the first sealing steel ball 10 from coming out of the first oil outlet 3.

[0029] Preferably, a first spring is further provided in the oil inlet cavity. The first spring is located between the first sealing steel ball 10 and the limiting block 11, further improving the sensitivity of the first sealing steel ball 10 to reset. When the negative pressure in the plunger cavity 6 is lower than the threshold value, the first sealing steel ball 10 can quickly reset under the action of the first spring to seal the communication port between the first cavity 8 and the second cavity 9.

[0030] Specifically, the oil outlet cavity includes a third cavity 12 and a fourth cavity 13. The second oil inlet 4 is opened at the part where the third cavity 12 communicates with the plunger cavity 6, and the second oil outlet 5 is opened at the part where the fourth cavity 13 communicates with the oil outlet pipeline. The second sealing element includes a second sealing steel ball 14 and a second spring 15. The outer diameter of the second sealing steel ball 14 is larger than the inner diameter of the third cavity 12 and smaller than the inner diameter of the fourth cavity 13. A limiting component is provided at the second oil outlet 5, and the second spring 15 is located between the second sealing steel ball 14 and the limiting component. When the plunger 7 is driven to slide towards the valve seat 1, a positive pressure is formed in the plunger cavity 6. When the positive pressure exceeds the threshold value, the second spring 15 is compressed, and the second sealing steel ball 14 leaves the communication port between the third cavity 12 and the fourth cavity 13. The fluid in the plunger cavity 6 is pumped out from the second oil outlet 5 through the oil outlet cavity.

[0031] Further, the limiting component is a plug 16. The plug 16 is provided with a shaft hole 17, and the shaft hole 17 communicates with the second oil outlet 5. The second spring 15 is located between the second sealing steel ball 14 and the plug 16.

[0032] Preferably, the plug 16 is screwed to the fourth cavity 13, which is convenient for adjusting the pre-tightening force of the second spring 15 according to requirements.

[0033] Optionally, the oil outlet cavity can also be designed as a conical cavity. The large end of the oil outlet cavity communicates with the oil outlet pipeline through the second oil outlet 5, and the small end of the oil outlet cavity communicates with the plunger cavity 6 through the second oil inlet 4. The second sealing element includes a second sealing steel ball 14 and a second spring 15. The outer diameter of the second sealing steel ball 14 is larger than the inner diameter of the small end of the oil outlet cavity and smaller than the inner diameter of the large end of the oil outlet cavity. A limiting component is provided at the second oil outlet 5, and the second spring 15 is located between the second sealing steel ball 14 and the limiting component.

[0034] In the second aspect of the embodiment of the present invention, a plunger pump is provided, which includes a driving component and the above-mentioned one-way valve. The driving component is used to drive the plunger 7 to reciprocate linearly in the plunger cavity 6, so as to form a positive pressure - negative pressure - positive pressure cycle in the plunger cavity 6 and realize continuous oil supply.

[0035] The working principle of the plunger pump in this embodiment is as follows:

[0036] First, drive the plunger 7 to displace in a direction away from the valve seat 1 through a driving component (such as a motor). A negative pressure is generated in the plunger chamber 6. Under the action of the negative pressure, the first sealing steel ball 10 disengages from the communication port between the first chamber 8 and the second chamber 9. The first chamber 8 communicates with the second chamber 9. The hydraulic oil in the fuel tank enters the plunger chamber 6 through the oil inlet pipeline, the first chamber 8, and the second chamber 9 under the action of the negative pressure (as Figure 2 shown). The negative pressure in the plunger chamber 6 is offset, and the first sealing steel ball 10 resets to its initial position under the loss of the negative pressure. Then, drive the plunger 7 to displace in a direction close to the valve seat 1 through the motor. A positive pressure is generated in the plunger chamber 6. This positive pressure also presses the first sealing steel ball 10 tightly against the communication port between the first chamber 8 and the second chamber 9 to prevent the hydraulic oil in the plunger chamber 6 from flowing back to the oil inlet pipeline from the oil inlet chamber. When the positive pressure in the plunger chamber 6 is greater than the elastic force of the second spring 15, the second spring 15 is compressed, and the second sealing steel ball 14 disengages from the communication port between the third chamber 12 and the fourth chamber 13. The third chamber 12 communicates with the fourth chamber 13. The hydraulic oil in the plunger chamber 6 flows out to the oil outlet pipeline through the third chamber 12 and the fourth chamber 13 (as Figure 3 shown), thus completing a cycle of pumping oil.

[0037] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A one-way valve, characterized in that: The invention comprises a valve seat (1), wherein an oil inlet cavity and an oil outlet cavity are arranged in the valve seat (1), wherein a first oil inlet port (2) of the oil inlet cavity is communicated with an oil inlet pipeline, and a second oil outlet port (5) of the oil outlet cavity is communicated with an oil outlet pipeline, and the first oil outlet port (3) of the oil inlet cavity and the second oil inlet port (4) of the oil outlet cavity are communicated with a plunger cavity (6), and a plunger (7) is slidably mounted in the plunger cavity (6); a first sealing element is arranged in the oil inlet cavity, and a second sealing element is arranged in the oil outlet cavity, and the first sealing element and the second sealing element are configured as follows: The first sealing element and the second sealing element are in a normally closed state. When the negative pressure in the plunger cavity (6) exceeds a threshold value, the first sealing element opens; when the positive pressure in the plunger cavity (6) exceeds a threshold value, the second sealing element opens.

2. A one-way valve according to claim 1, characterized in that: The oil inlet chamber comprises a first chamber (8) and a second chamber (9) which are connected to each other; the first oil inlet port (2) is provided at a position where the first chamber (8) is connected to the oil inlet pipeline; the second oil inlet port (4) is provided at a position where the second chamber (9) is connected to the plunger chamber (6); the first sealing element comprises a first sealing steel ball (10); the outer diameter of the first sealing steel ball (10) is greater than the inner diameter of the first chamber (8) and smaller than the inner diameter of the second chamber (9).

3. A one-way valve according to claim 1, characterized in that: The oil inlet chamber is a conical chamber, and the small end of the oil inlet chamber is connected to the oil inlet pipeline through a first oil inlet port (2), and the large end of the oil inlet chamber is connected to the plunger chamber (6) through a first oil outlet port (3); the first sealing element comprises a first sealing steel ball (10), and the outer diameter of the first sealing steel ball (10) is larger than the inner diameter of the small end of the oil inlet chamber and smaller than the inner diameter of the large end of the oil inlet chamber.

4. A one-way valve according to claim 2 or 3, characterized in that: A limiting block (11) is provided at the first oil outlet (3) of the oil inlet chamber.

5. A one-way valve as claimed in claim 4, characterized in that: A first spring is also provided in the oil inlet cavity, and the first spring is located between the first sealing steel ball (10) and the limiting block (11).

6. A one-way valve as claimed in claim 1, characterized in that: The oil outlet chamber comprises a third chamber (12) and a fourth chamber (13); the second oil inlet (4) is arranged at a position where the third chamber (12) is connected to the plunger chamber (6); the second oil outlet (5) is arranged at a position where the fourth chamber (13) is connected to the oil outlet pipeline; the second sealing element comprises a second sealing steel ball (14) and a second spring (15); the outer diameter of the second sealing steel ball (14) is larger than the inner diameter of the third chamber (12) and smaller than the inner diameter of the fourth chamber (13); the second oil outlet (5) is provided with a limit assembly, and the second spring (15) is located between the second sealing steel ball (14) and the limit assembly.

7. A one-way valve according to claim 6, characterized in that: The limit assembly is a plug (16), the plug (16) is provided with an axial hole (17), the axial hole (17) is communicated with the second oil outlet (5), and the second spring (15) is located between the second sealing steel ball (14) and the plug (16).

8. A one-way valve as claimed in claim 7, characterized in that: The plug (16) is threadedly connected to the fourth cavity (13).

9. A one-way valve as claimed in claim 1, characterized in that: The oil outlet chamber is a conical chamber, and the large end of the oil outlet chamber is connected to the oil outlet pipeline through the second oil outlet port (5), and the small end of the oil outlet chamber is connected to the plunger chamber (6) through the second oil inlet port (4); the second sealing element comprises a second sealing steel ball (14) and a second spring (15), the outer diameter of the second sealing steel ball (14) is larger than the inner diameter of the small end of the oil outlet chamber and smaller than the inner diameter of the large end of the oil outlet chamber; the second oil outlet port (5) is provided with a limit assembly, and the second spring (15) is located between the second sealing steel ball (14) and the limit assembly.

10. A plunger pump, characterized in that: It comprises a driving component and a one-way valve as claimed in any one of claims 1 to 9, wherein the driving component is used to drive a plunger (7) to perform linear reciprocating motion in a plunger cavity (6).

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