A pneumatic control structure for a high-frequency, durable pneumatic booster oil pump

Abstract

This invention discloses a pneumatic control structure for a high-frequency, durable pneumatic booster pump, comprising: a first cylinder with a movable first piston inside, which divides the interior of the first cylinder into a first air chamber and a second air chamber; a second cylinder nested within the second air chamber, with a movable second piston inside, which divides the interior of the second cylinder into a third air chamber and a fourth air chamber, the third and second air chambers being interconnected; an oil cylinder mounted at the bottom end of the first cylinder, a connecting rod assembly passing through the first and second pistons, the lower end of the connecting rod assembly extending into the oil cylinder; an oil inlet at the bottom end of the oil cylinder, and an oil outlet at the bottom end of the first cylinder, both of which are connected to the interior of the oil cylinder. This invention offers low cost and high reliability; high-frequency response and stable oil pressure; constant boost ratio double-acting output; and free switching between single and double-acting modes.

Description

Technical Field

[0001] This invention relates to the technical field of pneumatic oil pumps and related fields, and in particular to a pneumatic control structure for a high-frequency, durable pneumatic booster oil pump. Background Technology

[0002] The principle of a pneumatic booster pump is to use compressed air to drive a piston in reciprocating motion, thereby boosting the hydraulic oil pressure through the air-liquid area ratio. Existing pneumatic booster pump pneumatic control structures can be divided into two categories: one is the single-acting pneumatic booster pump pneumatic control structure (see...). Figure 1 As shown): Compressed air enters the P port of the pneumatic two-position three-way valve. When the pneumatic control valve is opened, the compressed air exits from the A port and enters the cylinder A chamber of the pump body. It acts on the cylinder piston and moves downward through the connecting rod to pressurize the liquid oil in the oil chamber. Oil is discharged from the oil outlet. When the piston assembly moves to the bottom, the two-position three-way valve is activated. The gas in the cylinder A chamber is discharged from the valve's T port. The cylinder B chamber is connected to the outside atmosphere and is equipped with a compression spring. The piston moves upward under the thrust of the spring. Oil is introduced into the oil chamber through the negative pressure oil inlet. When it reaches the top, the pneumatic control valve opens and the cycle repeats. Second, the pneumatic control structure of the double-acting pneumatic booster oil pump (see...) Figure 2 and 3 (As shown): Compressed air enters port P of the pneumatic two-position five-way valve. When the pneumatic control valve opens, the compressed air exits from port A and enters the pump body's air chamber A, acting on the cylinder piston and moving downwards via the connecting rod to pressurize the liquid medium in oil chamber D. Oil exits from the oil outlet of chamber D. Air chamber B exhausts from port T through port B of the two-position five-way valve. Oil chamber C draws oil from the oil inlet under negative pressure. When the piston assembly reaches the bottom, the two-position five-way valve actuates, and compressed air exits from port B and enters the pump body's air chamber B, acting on the cylinder piston and moving upwards via the connecting rod to pressurize the liquid medium in oil chamber C. Oil exits from the oil outlet of chamber C. Air chamber A exhausts from port T through port A of the two-position five-way valve. Oil chamber D draws oil from the oil inlet under negative pressure. When it reaches the top, the pneumatic control valve actuates and reciprocates.

[0003] However, the aforementioned prior art has the following drawbacks: 1. Single-acting pneumatic booster pumps rely on internal springs for reset. Due to spring fatigue deformation and response lag under high-frequency conditions, the pump's operating frequency is limited, its service life is short, and it cannot achieve continuous high-pressure output.

[0004] 2. Although the double-acting pneumatic booster pump eliminates the spring, it must use a complex two-position five-way valve for air circuit switching. This not only increases the cost and failure rate of the pneumatic control system, but also causes the compressed air in the original working air chamber to be directly emptied at the moment of reversal, resulting in a lack of auxiliary thrust when the piston reverses, slow reversal response speed, and consequently causing large pulsations and fluctuations in the output oil pressure.

[0005] 3. When existing double-acting pneumatic booster oil pumps run upward and downward, the cross-sectional area of ​​the oil chamber and the force-bearing area of ​​the air chamber are difficult to match perfectly, which often leads to inconsistent boosting ratios for downward and upward oil discharge and unstable output oil pressure. Moreover, existing products can usually only be used as single-acting or double-acting pumps, which has poor versatility and cannot be flexibly switched according to working conditions. Summary of the Invention

[0006] In view of this, in order to solve the above problems, the purpose of this invention is to provide a pneumatic control structure for a high-frequency, durable pneumatic booster oil pump, comprising: First cylinder, second cylinder, hydraulic cylinder, connecting rod assembly, two-position three-way valve; The first cylinder has a movable first piston inside, which divides the interior of the first cylinder into a first air chamber and a second air chamber. The second cylinder is fixedly nested inside the second air chamber. A second piston is movably installed inside the second cylinder. The second piston divides the interior of the second cylinder into a third air chamber and a fourth air chamber. The third air chamber and the second air chamber are interconnected. The hydraulic cylinder is installed at the bottom end of the first cylinder, the connecting rod assembly passes through the first piston and the second piston, and the lower end of the connecting rod assembly extends into the hydraulic cylinder; The two-position three-way valve has an air inlet, a working port, and an exhaust port. The air inlet is used to introduce compressed air, the working port is connected to the first air chamber, and the air inlet is connected to the fourth air chamber through the main air passage. The exhaust port is equipped with a muffler. The exhaust port is divided into a first exhaust branch and a second exhaust branch through an external diversion pipe. The first exhaust branch is connected to the air through the muffler and is also connected to the main air passage. The second exhaust branch is connected to the second air chamber. When the two-position three-way valve is in the first working position, the air inlet and the working port are connected. Compressed air enters the first air chamber through the air inlet and the working port, driving the first piston and the connecting rod assembly to move downward synchronously. The gas in the second air chamber is discharged through the second exhaust branch, the exhaust port and the first exhaust branch. The gas in the fourth air chamber is squeezed out by the second piston and enters the first air chamber through the main air passage and the air inlet, realizing gas recovery and reuse. When the two-position three-way valve switches to the second working position, compressed air continuously enters the fourth air chamber through the main air passage, driving the second piston and the connecting rod assembly to move upward synchronously; the working port and the exhaust port are connected, and the gas in the first air chamber is split through the working port and the exhaust port, with a portion of the gas entering the second air chamber through the second exhaust branch, cooperating with the driving force of the fourth air chamber to provide auxiliary thrust for the connecting rod assembly to switch upward, until the gas pressure in the second air chamber is equal to atmospheric pressure through the first exhaust branch; The bottom end of the hydraulic cylinder is provided with an oil inlet, and the bottom end of the first cylinder is provided with an oil outlet. Both the oil inlet and the oil outlet are connected to the inside of the hydraulic cylinder.

[0007] The pneumatic control structure of the aforementioned high-frequency durable pneumatic booster oil pump includes an oil outlet one-way valve.

[0008] The above-mentioned high-frequency durable pneumatic booster pump pneumatic control structure includes a third piston connected to the bottom end of the connecting rod assembly. The third piston is movably and sealed inside the oil cylinder, dividing the inside of the oil cylinder into a first oil chamber and a second oil chamber. The bottom end of the connecting rod assembly is provided with a connecting channel, and the third piston is provided with a through hole. The connecting channel and the through hole are connected to each other, so that the first oil chamber and the second oil chamber are connected.

[0009] The pneumatic control structure of the aforementioned high-frequency durable pneumatic booster oil pump includes a one-way valve within the connecting channel.

[0010] The pneumatic control structure of the aforementioned high-frequency durable pneumatic booster oil pump includes an oil inlet check valve inside the oil inlet.

[0011] The above-mentioned high-frequency durable pneumatic booster pump pneumatic control structure includes a position detection stroke valve at the end of the first cylinder. The position detection stroke valve is connected to the two-position three-way valve for control. When the connecting rod assembly moves to near the upper or lower end, the two-position three-way valve is switched between the air inlet and the working port and between the working port and the exhaust port.

[0012] The positive effects of the above technical solution compared with the existing technology are: 1. Low cost and high reliability: Through the innovative "differential cylinder" structure (first and second cylinders nested), a simple two-position three-way valve is cleverly used to replace the two-position five-way valve that must be used in traditional double-acting pumps, which greatly simplifies the pneumatic control pipeline and reduces manufacturing costs and valve body failure rate in the later stage.

[0013] 2. High-frequency response and stable oil pressure: When the piston finishes reversing downwards, the two-position three-way valve divides the compressed air in the first air chamber that has not been emptied into two paths through the exhaust port. One path is directly introduced into the fourth air chamber (atmospheric pressure chamber) to provide a brief upward thrust to the piston assembly (exhaust residual pressure is recovered and utilized). This effectively overcomes the static friction and inertia during piston reversal, greatly improves the reversing response speed, reduces oil pressure fluctuations, and enables the pump to adapt to higher frequency operating conditions.

[0014] 3. Equal boost ratio double-acting output: In double-acting mode, by setting a third piston with a connecting channel and a one-way valve in the cylinder, the oil chamber is divided into a first oil chamber and a second oil chamber. As long as the force-bearing areas (S1, S2, S3, S4) of the first piston, second piston, and third piston are reasonably configured to satisfy the formula (S1-S2) / S3=S2 / S4, the boost ratio of the output oil pressure and the input air pressure can be made completely consistent when the piston moves upward and downward, ensuring the absolute stability of the system pressure.

[0015] 4. Free switching between single / double-acting modes: This pneumatic control structure has extremely strong versatility. When used as a single-acting pump, it is only necessary to directly connect the first oil chamber and the second oil chamber (removing the cross-sectional area limitation) and move the one-way valve to the oil outlet. There is no need to change the main cylinder structure, which greatly enriches the applicable scenarios of the product.

[0016] 5. Long service life due to springless design: The return spring in traditional single-acting pumps is completely eliminated, thus removing the risk of spring fatigue and breakage. Combined with a scientific air circuit buffer design, the overall service life of the pneumatic booster oil pump is significantly improved. Attached Figure Description

[0017] Figures 1 to 3 This is a schematic diagram of the prior art.

[0018] Figure 4 This is a schematic diagram of the gas and oil circuit structure in the dual-action working mode of the present invention.

[0019] Figure 5 This is a schematic diagram of the structure of the present invention in its single-action working mode.

[0020] 1. First cylinder; 2. Second cylinder; 3. Oil cylinder; 4. Connecting rod assembly; 5. Two-position three-way valve; 6. First air chamber; 7. Second air chamber; 8. Third air chamber; 9. Fourth air chamber; 10. Oil inlet; 11. Oil outlet; 12. Oil outlet check valve; 13. First piston; 14. Second piston; 15. Third piston; 16. Connecting passage; 17. Oil inlet check valve; 18. First oil chamber; 19. Second oil chamber; 20. Check valve; 21. First exhaust branch; 22. Second exhaust branch. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0022] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0023] like Figures 4 to 5 The diagram shows a preferred embodiment of a high-frequency durable pneumatic booster pump with a pneumatic control structure, comprising: a first cylinder 1, a second cylinder 2, an oil cylinder 3, a connecting rod assembly 4, and a two-position three-way valve 5.

[0024] A first piston 13 is movably mounted inside the first cylinder 1, dividing the interior of the first cylinder 1 into a first air chamber 6 and a second air chamber 7. A second cylinder 2 is fixedly nested within the second air chamber 7, and a second piston 14 is movably mounted inside the second cylinder 2, dividing the interior of the second cylinder 2 into a third air chamber 8 and a fourth air chamber 9, which are interconnected. A hydraulic cylinder 3 is mounted at the bottom end of the first cylinder 1, and a connecting rod assembly 4 passes through the first piston 13 and the second piston 14, and is connected to the first piston 13 and... The second piston 14 is fixedly connected, and the lower end of the connecting rod assembly 4 extends into the cylinder 3; the two-position three-way valve 5 has an inlet, a working port, and an exhaust port. The inlet is used to introduce compressed air, the working port is connected to the first air chamber 6, the inlet is connected to the fourth air chamber 9 through the main air passage, and the exhaust port is equipped with a muffler. The exhaust port is divided into a first exhaust branch 21 and a second exhaust branch 22 through an external branch pipe. The first exhaust branch 21 is connected to the air through the muffler and is also connected to the main air passage. The second exhaust branch 22 is connected to the second air chamber 7; when the two... When the two-position three-way valve 5 is in the first working position, the inlet and the working port are connected. Compressed air enters the first air chamber 6 through the inlet and the working port, driving the first piston 13 and the connecting rod assembly 4 to move downwards synchronously. The gas in the second air chamber 7 is discharged through the second exhaust branch 22, the exhaust port, and the first exhaust branch 21. The gas in the fourth air chamber 9 is squeezed out by the second piston 14 and enters the first air chamber 6 through the main air passage and the inlet, realizing gas recovery and reuse. When the two-position three-way valve 5 is switched to the second working position, compressed air continuously enters the fourth air chamber 9 through the main air passage, driving the second piston 13 and the connecting rod assembly 4 to move downwards synchronously. Piston 14 and connecting rod assembly 4 move upward synchronously; the working port and the exhaust port are connected, and the gas in the first air chamber 6 is split through the working port and the exhaust port. A portion of the gas enters the second air chamber 7 through the second exhaust branch 22, which cooperates with the driving force of the fourth air chamber 9 to provide auxiliary thrust for the connecting rod assembly 4 to reverse upward, until the gas pressure in the second air chamber 7 is equal to the atmospheric pressure through the first exhaust branch 21; the bottom end of the oil cylinder 3 is provided with an oil inlet 10, and the bottom end of the first air cylinder 1 is provided with an oil outlet 11. Both the oil inlet 10 and the oil outlet 11 are connected to the inside of the oil cylinder 3.

[0025] In addition to the above, the present invention also has the following embodiments: Furthermore, a pneumatic control structure for a high-frequency, durable pneumatic booster oil pump includes an oil outlet 11 equipped with an oil outlet check valve 12. Specifically, excess oil in the oil cylinder 3 can be discharged from the interior of the oil cylinder 3 through the oil outlet check valve 12.

[0026] Furthermore, a pneumatic control structure for a high-frequency durable pneumatic booster pump is provided, wherein the bottom end of the connecting rod assembly 4 is connected to a third piston 15, the third piston 15 is movably and sealed inside the oil cylinder 3, the third piston 15 divides the inside of the oil cylinder 3 into a first oil chamber 18 and a second oil chamber 19, the bottom end of the connecting rod assembly 4 is provided with a connecting channel 16, the third piston 15 is provided with a through hole, the connecting channel 16 and the through hole are connected, so that the first oil chamber 18 and the second oil chamber 19 are connected.

[0027] Furthermore, a pneumatic control structure for a high-frequency durable pneumatic booster oil pump is provided, wherein a one-way valve 20 is provided in the connecting channel 16, the one-way valve 20 allows oil to flow from the second oil chamber 19 to the first oil chamber 18, and prevents oil from flowing from the first oil chamber 18 to the second oil chamber 19.

[0028] Furthermore, a pneumatic control structure for a high-frequency, durable pneumatic booster pump includes an inlet check valve 17 within the oil inlet 10. Specifically, the inlet check valve 17 controls the oil flow to enter the cylinder 3 only from the oil inlet 10.

[0029] Furthermore, a pneumatic control structure for a high-frequency durable pneumatic booster oil pump is provided, wherein a position detection stroke valve is provided at the end of the first cylinder 1. The position detection stroke valve is connected to a two-position three-way valve 5 for control. When the connecting rod assembly 4 moves to near the upper or lower end, the two-position three-way valve 5 is controlled to switch between the air inlet and the working port and between the working port and the exhaust port.

[0030] In actual use, this pneumatic control structure has a dual-acting working mode. In the dual-acting working mode: the lower end of the connecting rod assembly 4 is connected to the third piston 15, which divides the inside of the cylinder 3 into a first oil chamber 18 and a second oil chamber 19; the first piston 13 has a first force-bearing area S1, and the second piston 14 has a second force-bearing area S2. The first force-bearing area S1 is the cross-sectional area of ​​the first piston 13 facing the first air chamber 6; the second force-bearing area S2 is the cross-sectional area of ​​the second piston 14 facing the fourth air chamber 9; the cross-sectional area of ​​the connecting rod assembly 4 is the third force-bearing area S3; and the third piston 15 has a fourth force-bearing area S4 on the side of the first oil chamber 18.

[0031] Compressed air (pressure P1) enters the fourth air chamber 9 simultaneously through two paths, acting on the second piston 14 and the inlet P of the two-position three-way valve 5. Under the action of internal air pressure, the inlet P of the two-position three-way valve 5 is connected to the working port A, and the compressed air exits from the working port A and enters the first air chamber 6, acting on the first piston 13. Because the force-bearing area S1 of the first piston 13 is greater than the force-bearing area S2 of the second piston 14, the connecting rod assembly 4 experiences a downward force equal to P1 × (S1 - S2), causing it to move downwards. At this time, the volume of the second air chamber 7 decreases, and the gas passes through the silencer. The oil in the second oil chamber 19 is discharged and enters the first oil chamber 18 through the check valve 20. When moving downwards, the hydraulic oil in the second oil chamber 19 is forced into the first oil chamber 18 through the check valve 20, causing the pressure in the first oil chamber 18 to increase. The high-pressure oil opens the oil outlet check valve 12 and is discharged from the oil outlet 11. The output oil pressure P2 = P1 × (S1 - S2) / S3. When the connecting rod assembly 4 moves close to the bottom end, the position detection stroke valve at the upper end of the first cylinder 1 controls the working port A of the two-position three-way valve 5 to be connected to the exhaust port T. The high-pressure gas enters the fourth air chamber 9 and acts on the... With the second piston moving upwards, the compressed air in the first air chamber 6 flows through the working port A to the exhaust port T, splitting into two paths. At the moment of reversal, the residual high-pressure gas in the first air chamber 6 that has not been completely released is directly introduced into the second air chamber 7 through the second exhaust branch 22. Since the exhaust from the first exhaust branch 21 is continuous, a momentary pulse of high pressure is generated in the second air chamber 7, acting on the first piston (S1-S3) and the second piston S2. The force-bearing area is S1-S2-S3, providing a brief upward thrust to the connecting rod assembly 4. This method can improve the reversing response speed of the connecting rod assembly 4. To reduce oil pressure fluctuations, the connecting rod assembly 4 moves upward, reducing the volume of the first oil chamber 18 and creating high pressure. The high-pressure oil opens the oil outlet check valve 12 and discharges from the oil outlet 11, outputting oil pressure P3 = P1 × S2 / S4. Simultaneously, the volume of the second oil chamber 19 increases, creating negative pressure, which draws oil through the oil inlet 10. When the connecting rod assembly 4 approaches the top dead center, the position detection stroke valve is triggered, resetting the two-position three-way valve 5. The air inlet P and the working port A are connected again, achieving reciprocating operation. Under the self-control of the two-position three-way valve 5, the air inlet P and the working port A are connected, thus achieving reciprocating operation.

[0032] Furthermore, when used as a double-acting pneumatic booster pump, in order to ensure that the output oil pressure of the connecting rod assembly 4 is the same as the input air pressure boost ratio when it moves upward and downward, it is only necessary to adjust the values ​​of S1, S2, S3, and S4 so that the equation (S1-S2) / S3= S2 / S4 holds true. This ensures that the hydraulic boost ratio when the piston moves downward is mathematically equal to the hydraulic boost ratio when it moves upward.

[0033] This pneumatic control structure has a single-acting working mode. In the single-acting working mode, the second oil chamber 19 does not output high-pressure oil, that is, the effective pressure-bearing area on the side of the second oil chamber 19 is 0. In the single-acting mode, the division of the cylinder 3 by the third piston 15 can be cancelled, and the one-way valve 20 on the third piston can be removed or made to be normally open. The first oil chamber 18 and the second oil chamber 19 are integrated into one oil chamber. At this time, the pressure-bearing area at the bottom of the connecting rod assembly 4 is set to S3', and the pressure ratio is (S1-S2) / S3'.

[0034] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A pneumatic control structure for a high-frequency, durable pneumatic booster oil pump, characterized in that, include: First cylinder, second cylinder, hydraulic cylinder, connecting rod assembly, two-position three-way valve; The first cylinder has a movable first piston inside, which divides the interior of the first cylinder into a first air chamber and a second air chamber. The second cylinder is fixedly nested inside the second air chamber. A second piston is movably installed inside the second cylinder. The second piston divides the interior of the second cylinder into a third air chamber and a fourth air chamber. The third air chamber and the second air chamber are interconnected. The hydraulic cylinder is installed at the bottom end of the first cylinder, the connecting rod assembly passes through the first piston and the second piston, and the lower end of the connecting rod assembly extends into the hydraulic cylinder; The two-position three-way valve has an air inlet, a working port, and an exhaust port. The air inlet is used to introduce compressed air, the working port is connected to the first air chamber, and the air inlet is connected to the fourth air chamber through the main air passage. The exhaust port is equipped with a muffler. The exhaust port is divided into a first exhaust branch and a second exhaust branch through an external diversion pipe. The first exhaust branch is connected to the air through the muffler and is also connected to the main air passage. The second exhaust branch is connected to the second air chamber. When the two-position three-way valve is in the first working position, the air inlet and the working port are connected. Compressed air enters the first air chamber through the air inlet and the working port, driving the first piston and the connecting rod assembly to move downward synchronously. The gas in the second air chamber is discharged through the second exhaust branch, the exhaust port and the first exhaust branch. The gas in the fourth air chamber is squeezed out by the second piston and enters the first air chamber through the main air passage and the air inlet, realizing gas recovery and reuse. When the two-position three-way valve switches to the second working position, compressed air continuously enters the fourth air chamber through the main air passage, driving the second piston and the connecting rod assembly to move upward synchronously; the working port and the exhaust port are connected, and the gas in the first air chamber is split through the working port and the exhaust port, with a portion of the gas entering the second air chamber through the second exhaust branch, cooperating with the driving force of the fourth air chamber to provide auxiliary thrust for the connecting rod assembly to switch upward, until the gas pressure in the second air chamber is equal to atmospheric pressure through the first exhaust branch; The bottom end of the hydraulic cylinder is provided with an oil inlet, and the bottom end of the first cylinder is provided with an oil outlet. Both the oil inlet and the oil outlet are connected to the inside of the hydraulic cylinder.

2. The pneumatic control structure of a high-frequency durable pneumatic booster oil pump according to claim 1, characterized in that, The oil outlet is equipped with an oil outlet check valve.

3. The pneumatic control structure of a high-frequency durable pneumatic booster oil pump according to claim 1, characterized in that, The bottom end of the connecting rod assembly is connected to a third piston. The third piston is movable and sealed inside the oil cylinder. The third piston divides the inside of the oil cylinder into a first oil chamber and a second oil chamber. The bottom end of the connecting rod assembly is provided with a connecting channel, and the third piston is provided with a through hole. The connecting channel and the through hole are connected to each other so that the first oil chamber and the second oil chamber are connected.

4. The pneumatic control structure of a high-frequency durable pneumatic booster oil pump according to claim 3, characterized in that, A one-way valve is installed in the connecting channel.

5. The pneumatic control structure of a high-frequency durable pneumatic booster oil pump according to claim 1, characterized in that, The oil inlet is equipped with an oil inlet check valve.

6. The pneumatic control structure of a high-frequency durable pneumatic booster oil pump according to claim 1, characterized in that, The end of the first cylinder is provided with a position detection stroke valve, which is controlled and connected to the two-position three-way valve. When the connecting rod assembly moves to near the upper or lower end, the two-position three-way valve is controlled to switch between the air inlet and the working port and between the working port and the exhaust port.

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