Air-tight piston air pump

Abstract

An air-tight piston air pump comprises a universal piston air pump, a sealing protective cover and a pressure balance module. A universal piston air pump comprises a motor, a crank, a piston ring, a piston, a valve plate and a pump head. The outer side of the piston ring is sequentially connected with the valve plate and the pump head, a cavity for containing and fixing the motor is formed in the sealing protective cover, a crank is installed on an output bearing of the motor, a piston ring installation hole is formed in a sealing protective cover shell pointed by the perpendicular line of the crank shaft, and the piston ring, the valve plate and the pump head are installed outside the sealing protective cover shell through the piston ring installation hole. The piston is arranged in the piston ring; a piston connecting rod is connected with the crank; the piston ring mounting hole, the piston ring, the valve plate and the pump head are in sealed connection pairwise; the pressure balance module comprises an on-off valve which is opened and closed instantly when the motor is started, an inlet of the on-off valve is communicated with the air inlet of the air pump and the inner cavity of the sealing protective cover, and an outlet of the on-off valve is communicated with the air outlet of the air pump. The whole structure is compact, the size is small, the sealing performance is good, and gas is not leaked during working.

Description

Technical Field

[0001] This invention belongs to the field of air pump sealing technology, specifically relating to a leak-proof piston air pump structure. Background Technology

[0002] Air pumps handle various gases during operation, including toxic, flammable, explosive, and corrosive gases. Therefore, efficient sealing technology is crucial for preventing gas leaks, protecting equipment, and maintaining stable system operation. Particularly important is the recovery of exhaust gas after insulating gas testing of high-voltage electrical equipment. Air pumps are used to force the exhaust gas back into the testing equipment. Even trace amounts of air or moisture infiltration during this process can degrade the insulating properties of the insulating gas, potentially leading to internal discharge or even explosions within the high-voltage electrical equipment, causing significant losses during maintenance. In applications like this, in addition to extremely high requirements for pipeline sealing, the airtightness of the air pump is also paramount.

[0003] However, the pistons, crankshafts, and motors of all piston air pumps currently on the market cannot achieve a strict seal. This not only results in a large amount of gas leakage, but also causes a large amount of air and moisture to enter during the recharging process, posing a fatal threat to the safe operation of high-voltage electrical equipment.

[0004] This application relates to a well-sealed air pump that solves the problem of gas leakage and air infiltration caused by poor sealing in general piston air pumps on the market. Summary of the Invention

[0005] To address the shortcomings of existing general-purpose piston air pumps, where poor sealing at the piston, crankshaft, and motor always leads to gas leakage, this invention provides a leak-proof piston air pump.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] An airtight piston pump, comprising a conventionally designed general-purpose piston pump, a sealed protective cover, and a pressure balancing module;

[0008] The general-purpose piston air pump includes a motor, crank, piston rings, piston, valve plate, and pump head;

[0009] The outer end face of the piston ring is connected to the valve plate, and the outer end face of the valve plate is connected to the pump head.

[0010] The sealed protective cover has a chamber for accommodating and fixing the motor. The output bearing of the motor is equipped with a crank. A piston ring mounting hole is opened on the sealed protective cover housing pointed to by the vertical line of the crank shaft. A piston ring sealing bushing is installed on the piston ring mounting hole. The piston ring sealing bushing is connected to the lower part of the piston ring. Through the piston ring sealing bushing, the piston ring, valve plate, and pump head are installed outside the sealed protective cover housing. The piston is installed inside the piston ring. The other end of the piston connecting rod is connected to the crank and moves axially back and forth inside the piston ring under the drive of the crank.

[0011] The piston ring mounting hole and the piston ring sealing bushing, the piston ring sealing bushing and the piston ring, the piston ring and the valve plate, and the valve plate and the pump head are sealed together. The sealed connection is that at least one of the contact surfaces of any two of the above has a sealing groove with an opening facing the other, and the sealing groove is filled with a sealing ring.

[0012] The pressure balancing module includes an on / off valve that opens and closes instantaneously upon motor startup. The inlet of the on / off valve is connected to both the air inlet of the universal piston air pump and the inner cavity of the sealing protective cover via a pipe, and the outlet of the on / off valve is connected to the air outlet of the universal piston air pump via a pipe.

[0013] Furthermore, the piston ring is mounted on the piston ring mounting hole via a piston ring sealing bushing. The piston sealing bushing is a hollow cylinder. The outer side of the piston ring sealing bushing is adapted to and sealed to the inner side of the piston ring mounting hole. The lower outer side of the piston ring is pressed and sealed to the inner side of the piston ring sealing bushing.

[0014] Furthermore, the shut-off valve is a normally closed solenoid valve.

[0015] Furthermore, a connector socket is also sealed and connected to the cavity wall of the sealed protective cover. The connector socket faces outward and is compatible with the connector plug for power distribution. The power supply and control lines of the motor inside the sealed protective cover are electrically connected to the connector socket, and then electrically connected to the external power supply or control signal through the connector plug.

[0016] Furthermore, the sealed protective cover housing is also equipped with a cover plate to accommodate the installation and access of the motor.

[0017] Furthermore, the air outlet and air inlet on the pump head are respectively connected to a high-pressure air outlet pipe and a low-pressure air inlet pipe.

[0018] Furthermore, the valve plate of the general-purpose piston air pump has an outlet hole and an inlet hole that penetrate the thickness of the valve plate. An outlet diaphragm is covering the top of the outlet hole, and an inlet diaphragm is installed below the inlet hole. The inlet and outlet diaphragms are designed to be semi-open. The pump head has an outlet channel and an inlet channel. The outlet channel is connected to the outlet hole on the valve plate, and an opening and closing space for the outlet diaphragm is also provided at the connection. The inlet channel is connected to the inlet hole on the valve plate. The interfaces of the outlet channel and the inlet channel to the outside are the outlet and the inlet, respectively.

[0019] The valve plate, outlet port, inlet port, inlet diaphragm, and outlet diaphragm of a general-purpose piston air pump constitute the suction and discharge valve design of the piston air pump.

[0020] Furthermore, the sealing protective cover housing has piston ring mounting holes, the center line of which is parallel to or coincides with the crankshaft vertical line. The inner wall of the piston ring mounting hole is a stepped hole that is narrow at the bottom and wide at the top. The piston sealing bushing is a hollow cylinder. The bottom outer side of the piston ring sealing bushing has a stepped groove that is wide at the bottom and narrow at the top. The stepped hole and the stepped groove are matched. The bottom outer side of the piston ring sealing bushing is fitted onto the inner wall of the piston ring mounting hole.

[0021] This invention features a sealed protective cover installed on the outside of a general-purpose air pump. Leaking gas enters the sealed protective cover, preventing external gas leakage and the ingress of outside air, thus ensuring absolute isolation between the internal air circuit of the air pump and the outside air. The piston rings, suction and discharge valves, and pump head (equivalent to the pump body) of the air pump are sealed to the outside of the protective cover via piston ring sealing bushings, and all these components are sealed together to ensure no leakage during piston movement and to prevent gas leakage from the protective cover. A pressure balancing module solves the problem of the sealed general-purpose air pump failing to start under pressure, and also solves the problem of residual gas inside the protective cover. The overall structure is compact, small in size, has good sealing performance, and prevents gas leakage during operation. This invention can be applied to the measuring instrument industry, where the measured gas is pressurized by a leak-free air pump, allowing for contamination-free recovery or refilling of the measured gas into specific containers or high-voltage electrical equipment.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. Through optimized structural design, this invention efficiently integrates the drive unit (motor), pump body (piston rings, suction / discharge valves, and pump head), and sealing system of the piston air pump, significantly reducing the size and footprint of the sealed pump. This makes it more suitable for installation in environments with limited space, expanding its application range.

[0024] 2. This invention employs reliable sealing technology, effectively preventing leakage of the working medium. This is particularly important for handling precious gases, toxic or harmful gases, or flammable and explosive gases (or substances), not only expanding the applicable scope and reducing resource waste, but also ensuring operator safety and environmental cleanliness. (Of course, when used with liquid substances, the piston pump must be replaced with a liquid piston pump).

[0025] 3. In addition to preventing internal media leakage, the excellent sealing performance of this invention can also effectively prevent external air, moisture and other contaminants from entering the pump. This is crucial for maintaining pump performance, extending service life and protecting the purity of sensitive media (such as high-purity gases, pharmaceuticals, etc.).

[0026] 4. The excellent sealing design of this invention reduces pressure fluctuations caused by leakage, ensuring the continuity and stability of the pumping process, which is extremely important for applications that require precise control of flow and pressure (such as chemical reactions, gas supply for precision instruments, etc.).

[0027] 5. This invention provides excellent sealing, reducing unnecessary leakage and making the pump more efficient. This means that less energy is required to transport the same volume or mass of fluid, contributing to energy conservation, emission reduction, and lower operating costs.

[0028] 6. The excellent sealing performance of this invention reduces leakage and external contamination, lowering maintenance frequency and repair costs. Due to reduced leakage and external contamination, wear on internal pump parts is lessened, extending maintenance cycles and service life, ultimately saving on maintenance and replacement costs in the long run.

[0029] In summary, this invention improves work efficiency, ensures operational safety, and reduces operating costs through its compact structure, high sealing performance, and effective blocking of external contaminants. More importantly, it is widely applicable to demanding industrial and scientific research fields. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the external structure of the present invention;

[0031] Figure 2 yes Figure 1 AA section view;

[0032] Figure 3 yes Figure 2 A magnified view of part C in the middle;

[0033] Figure 4 This is a schematic diagram of the air path of the pressure balance module of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] Figures 1-4In the middle, 1. Sealing protective cover, 2. Rubber shock absorber, 3. Sealing flange front cover plate, 4. Screw, 5. Spring washer, 6. Valve block, 10. On / off valve, 11. Sealing flange rear cover plate, 12. Connector socket, 13. Connector plug, 15. Motor, 17. First sealing ring, 18. Piston ring sealing bushing, 19. Piston ring, 20. Inlet diaphragm, 21. Second sealing ring, 22. Third sealing ring, 23. Pump head, 24. Valve plate, 25. Outlet diaphragm, 27. Inlet pipe, 28. Outlet pipe, 29. Gas pipeline. Detailed Implementation

[0036] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort should fall within the scope of protection of this invention.

[0037] It should be noted that the key structural components of the general-purpose piston air pump involved in this application, such as the motor 15, crank, piston ring 19, piston, suction / discharge valve, and pump head 23, are all existing parts or pipelines of the air pump. The suction / discharge valve includes a valve plate 24, an inlet diaphragm 20, and an outlet diaphragm 25. The valve plate 24 has an outlet hole and an inlet hole that penetrate the thickness of the valve plate. The outlet hole is covered by the outlet diaphragm 25, and the inlet diaphragm 20 is arranged below the inlet hole. The inlet diaphragm 20 and the outlet diaphragm 25 are designed to be semi-open to control the flow direction of the gas. The pump head 23 has an outlet channel and an inlet channel. The outlet channel on the pump head 23 is connected to the outlet hole on the valve plate 24, and a space for the opening and closing of the outlet diaphragm 25 is also provided at the connection point. The inlet channel on the pump head 23 is connected to the inlet hole on the valve plate 24. The interfaces between the outlet channel and the inlet channel on the pump head 23 and the outside are the outlet and inlet, respectively. The piston moves axially within the piston ring assembly, forming an airflow channel for low-pressure intake and high-pressure exhaust. Figure 1 Figure 2 and Figure 3 In the illustrated embodiment, the piston moves towards the pump head 23, closing the inlet diaphragm 20 and opening the outlet diaphragm 25 due to airflow, allowing compressed air to flow out through the outlet channel. As the piston moves downwards, the inlet diaphragm 20 opens, and the outlet diaphragm 25 is closed due to air pressure, allowing airflow to enter the inner cavity of the piston rings through the inlet channel. This cycle repeats continuously, creating a continuous intake and exhaust process. The intake / exhaust valves, high-pressure outlet channel, and low-pressure inlet channel cooperate with the piston's movement within the piston rings; this is existing technology for piston air pumps.

[0038] Furthermore, terms such as "outer end face" and "inner end face" refer to the inner cavity relative to the sealed protective cover 1. The "upward" and "downward" movements are for ease of... Figure 1 The direction of piston movement is explained in the illustrated embodiment. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] It should also be noted that, unless otherwise explicitly stated and limited, terms such as "connection," "installation," and "installation" should be interpreted broadly. This can refer to direct connection, connection via openings, or indirect connection via intermediate components.

[0040] Figure 1 , Figure 2 and Figure 3 An embodiment of a leak-proof piston air pump is given.

[0041] An airtight piston pump includes a conventional piston pump, a sealed protective cover 1, and a pressure balancing module.

[0042] The general-purpose piston air pump includes a motor 15, a crank, a piston ring 19, a piston, a valve plate 24, and a pump head 23;

[0043] The outer end face of the piston ring 19 is connected to the valve plate 24, and the outer end face of the valve plate 24 is connected to the pump head 23.

[0044] The sealed protective cover 1 has a chamber for accommodating and fixing the motor 15. The output bearing of the motor 15 is equipped with a crank. A piston ring mounting hole is opened on the housing of the sealed protective cover 1, which is pointed to by the vertical line of the crank shaft. A piston ring sealing bushing 18 is installed on the piston ring mounting hole. The piston ring sealing bushing 18 is connected to the lower part of the piston ring 19. Through the piston ring sealing bushing 18, the piston ring 19, valve plate 24, and pump head 23 are installed outside the housing of the sealed protective cover 1. The piston is installed inside the piston ring 19. The other end of the piston connecting rod is connected to the crank and moves axially back and forth inside the piston ring 19 under the drive of the crank.

[0045] The piston ring sealing bushing 18 is connected to the piston ring mounting hole, the piston ring sealing bushing 18 is connected to the piston ring 19, the outer end face of the piston ring 19 is connected to the inner side of the valve plate 24, and the outer side of the valve plate 24 is connected to the lower end face of the pump head 23 in a sealed connection. The sealed connection is that at least one of the contact surfaces of any two of the above has a sealing groove with an opening facing the other, and the sealing groove is filled with a sealing ring.

[0046] The pressure balancing module includes an on / off valve 10 that opens and closes instantly upon motor startup. The inlet of the on / off valve 10 is connected to both the air inlet of the air pump and the inner cavity of the sealing cover 1 via a pipe, and the outlet of the on / off valve 10 is connected to the air outlet of the air pump via a pipe.

[0047] Preferably, the piston ring 19 is mounted on the piston ring mounting hole via a piston ring sealing bushing 18. The piston sealing bushing 18 is a hollow cylinder. The outer side of the piston ring sealing bushing 18 is adapted to and sealed to the inner side of the piston ring mounting hole. The lower outer side of the piston ring 19 is pressed and sealed to the inner side of the piston ring sealing bushing 18.

[0048] Preferably, the on / off valve 10 is a normally closed solenoid valve.

[0049] Furthermore, a connector socket 12 is also sealed and connected to the cavity wall of the sealed protective cover 1. The connector socket 12 faces outward and is compatible with the connector plug 13 for electrical connection. The power supply and control line of the motor 15 inside the sealed protective cover 1 are electrically connected to the connector socket 12, and then electrically connected to the external power supply or control signal through the connector plug 13.

[0050] Furthermore, the sealed protective cover 1 is also provided with a cover plate to accommodate the installation and access of the motor 15.

[0051] Furthermore, the air outlet and air inlet on the pump head 23 are respectively connected to a high-pressure air outlet pipe 28 and a low-pressure air inlet pipe 27.

[0052] Furthermore, the valve plate 24 of the general-purpose piston air pump has an outlet hole and an inlet hole that penetrate the thickness of the valve plate. An outlet diaphragm 25 covers the top of the outlet hole, and an inlet diaphragm 20 is provided below the inlet hole. The inlet diaphragm 20 and the outlet diaphragm 25 are designed to be semi-open. The pump head 23 has an outlet channel and an inlet channel. The outlet channel is connected to the outlet hole on the valve plate 24. The connection point also has a space for the outlet diaphragm 25 to open and close. The inlet channel is connected to the inlet hole on the valve plate 24. The interfaces of the outlet channel and the inlet channel to the outside are the outlet and the inlet, respectively.

[0053] The valve plate 24, the outlet port, the inlet port, the inlet diaphragm 20, and the outlet diaphragm 25 of the general-purpose piston air pump constitute the suction and discharge valve design of the piston air pump.

[0054] Figure 2 An embodiment of a sealed protective cover is provided.

[0055] The sealed protective cover 1 has a chamber for accommodating and fixing the motor 15. In order to fix the sealed protective cover 1, the sealed protective cover 1 is divided into left and right chambers by a partition. The partition is provided with an output bearing mounting hole. The motor 15 is installed in the right chamber, and the output bearing of the motor 15 enters the left chamber through the mounting hole on the partition.

[0056] A connector socket 12 is installed on the wall of the right chamber. The wall is sealed to the connector socket 12. The connector socket 12 faces outward and is compatible with the connector plug 13 for electrical connection. The power supply and control line of the motor 15 inside the sealed protective cover 1 are electrically connected to the connector socket 12, and then electrically connected to the external power supply or control signal through the connector plug 13.

[0057] To facilitate the installation of the motor 15, the sealing cover 1 is designed to open from the rear. The rear sealing flange 11 is connected to the rear end face of the sealing cover 1 by screws. For ease of processing, the sealing cover 1 is designed symmetrically on the front and rear sides. The front sealing flange 3 is also connected to the front end face of the sealing cover 1 by screws 4. A spring washer 5 is inserted in front of the screw 4 to enhance the tightness with the front end face of the sealing cover 1. In fact, as long as the sealing cover 1 can achieve a sealing effect and isolate it from the outside atmosphere, any design is acceptable, and no specific restrictions are imposed here.

[0058] In the left chamber, one end of the crankshaft is fixedly connected to the motor output bearing. The piston is connected to the crankshaft via a connecting rod. A piston ring opening is provided on the housing of the sealing protective cover 1 corresponding to the crankshaft. Through the piston ring opening, the piston ring 19, valve plate 24, and pump head 23 of the general-purpose air pump are installed outside the housing of the sealing protective cover 1. The piston is installed inside the piston ring. The lower end of the piston connecting rod is connected to the crank and moves axially back and forth inside the piston ring under the drive of the crank.

[0059] The rear side of the sealing protective cover 1 is provided with a sealing flange rear cover plate 11 that is adapted to the rear end face of the sealing protective cover 1. The sealing flange rear cover plate 11 is sealed to the rear end face of the sealing protective cover 1. The sealing connection can be made using a sealing gasket, and the specific installation connection can be made using screws 4, which is not limited here.

[0060] The front side of the sealing protective cover 1 is provided with a sealing flange front cover plate 3 that is adapted to the front end face of the sealing protective cover 1, and the sealing flange front cover plate 3 is sealed to the front end face of the sealing protective cover 1. Figure 1 As shown, the two are connected by screw 4. To ensure a tight and secure connection, it is common practice to install a spring washer 5 at the front end of screw 4. Of course, using a sealing gasket is also feasible to achieve a sealed connection, and there is no specific limitation.

[0061] Figure 3 and Figure 2 An embodiment is provided that provides a piston ring sealing bushing 18 and a piston ring mounting hole, a piston ring sealing bushing 18 and a piston ring 19, and a sealing connection between the outer end face of the piston ring 19 and the inner end face of the valve plate 24, and between the outer end face of the valve plate 24 and the lower end face of the pump head 23.

[0062] The sealing connection is such that at least one of the contact surfaces of any two of the above has a sealing groove with an opening facing the other, and the sealing groove is filled with a sealing ring.

[0063] Figure 3 In the process, a first sealing ring 17 is provided between the piston ring sealing bushing 18 and the piston ring mounting hole step contact surface; a second sealing ring 21 is provided between the outer end face of the piston ring 19 and the inner end face of the valve plate 24; and a third sealing ring 22 is provided between the outer end face of the valve plate 24 and the lower end face of the pump head 23.

[0064] Figure 4 and Figure 1 An embodiment of a pressure balancing module is provided.

[0065] The pressure balancing module includes an on / off valve 10 that opens and closes instantly upon motor startup and a valve block 6. The on / off valve 10 is mounted on the valve block 6 through a mounting hole. The valve block 6 has an air inlet channel and an air outlet channel that are respectively connected to the inlet and outlet of the on / off valve 10. The air inlet channel is connected to the low-pressure air inlet pipe 27 of the air pump (i.e., connected to the air inlet of the air pump) and is also connected to the inner cavity of the sealing protective cover 1 through a gas pipe 29. The air outlet channel is connected to the high-pressure air outlet pipe 28 of the air pump (i.e., connected to the air outlet of the air pump).

[0066] Figure 3 An embodiment is provided in which a piston ring 19 is mounted to a sealing shield 1 housing via a piston ring sealing bushing 18.

[0067] The sealing cover 1 has a piston ring mounting hole on its housing. The center line of the piston ring mounting hole is parallel to or coincides with the vertical line of the crankshaft. The inner wall of the piston ring mounting hole is a stepped hole that is narrow at the bottom and wide at the top. The piston sealing bushing 18 is a hollow cylinder. The bottom outer side of the piston ring sealing bushing 18 has a stepped groove that is wide at the bottom and narrow at the top. The stepped hole and the stepped groove are adapted to each other. The bottom outer side of the piston ring sealing bushing 18 is fitted onto the inner wall of the piston ring mounting hole. The piston ring 19 is installed inside the piston ring sealing bushing 18. The lower outer side of the piston ring 19 is pressed and sealed to the inner side of the piston ring sealing bushing 18. The lower end face of the piston ring 19 is flush with the lower end face of the piston ring sealing bushing 18.

[0068] In this embodiment, the piston ring mounting hole is a circular hole, and the outer wall of the piston sealing bushing 18 is adapted to and sealed to the inner wall of the piston ring mounting hole, so the outer wall of the piston sealing bushing 18 is a circumferential surface; when the piston ring mounting hole is a square hole, the piston sealing bushing 18 has four square surfaces; here there are no specific restrictions on the piston ring mounting hole and the outer wall of the piston sealing bushing 18, as long as the two are adapted to and connected.

[0069] A rubber shock absorber 2 is installed at the bottom of the sealed protective cover 1.

[0070] This invention, by installing a sealed protective cover on the outside of a general-purpose air pump, prevents leaked gas from entering the sealed protective cover, thus ensuring absolute isolation between the internal air system of the air pump and the outside air. Piston ring 19 The suction and discharge valves and pump head 23 (equivalent to the pump body) are installed outside the sealing protective cover through piston ring sealing bushing 18, and these components are all sealed together to ensure that there is no air leakage when the piston moves, and also to prevent the gas inside the sealing protective cover from leaking out.

[0071] In this invention, the air circuit is first connected. Upon motor startup (start-up), the on / off valve 10 is briefly opened and closed to connect the air inlet, outlet, and inner cavity of the sealing shield 1 of the piston cylinder (a three-dimensional mechanism composed of piston rings and piston). This balances the pressure within the piston cylinder's air inlet, outlet, and sealing shield cavity, allowing the crankshaft to start normally. After the on / off valve 10 closes, the connection between the piston cylinder's air inlet and outlet is severed. During the opening and closing, the gas inside the air inlet and sealing cavity is drawn away by the movement of the air pump piston. If residual gas from the previous operation conflicts with subsequent operation, the low-pressure air inlet pipe 27 of the pump head is connected to purge gas; using purge gas for starting can then resolve the issue.

[0072] In summary, in this invention, the sealing cover 1 seals the motor 15 of the universal piston air pump; the piston ring 19, suction / discharge valve, and pump head 23 of the universal piston air pump are installed outside the piston ring mounting hole on the sealing cover 1 through the piston ring sealing bushing 18. The piston ring sealing bushing 18 is sealed to the piston ring mounting hole, to the piston ring 19, and the outer end face of the piston ring 19 is sealed to the inner end face of the valve plate 24, and the outer end face of the valve plate 24 is sealed to the lower end face of the pump head 23. Connect; install an on / off valve 10 that opens and closes instantly when the motor starts between the air inlet (low-pressure air inlet pipe 27) and the air outlet (high-pressure air outlet pipe 28) of the general-purpose piston air pump, so as to realize the interconnection between the air pump inlet, air outlet and the inner cavity of the sealing protective cover 1, so that the crankshaft can start normally. This avoids the adverse consequences of the crankshaft being unable to start due to the pressure imbalance on both sides of the piston when there is pressure in the air pump inlet or outlet or in the chamber where the crankshaft is located, which would lead to the motor 15 being blocked and the coil current being too large and damaged.

[0073] While many patent documents describe methods to prevent air leakage by using a three-dimensional sealing cover around the air pump, these methods typically enclose the entire air pump within the cover. While this achieves the desired seal, it significantly increases the overall size of the pump, which is no longer suitable for the trend towards miniaturization in instruments and equipment. This invention, however, only houses the motor portion of the air pump within the sealing cover. An airtight design is added between the piston ring 19, the suction / discharge valve, and the pump head 23, ensuring no leakage during piston movement and solving the problem of piston starting under pressure. This greatly reduces the pump's size and allows for applications involving precious, toxic, harmful, flammable, or explosive gases. It also reduces pressure fluctuations caused by leakage during operation, making it highly suitable for environments requiring precise flow and pressure control.

[0074] Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this invention shall fall within the protection scope of this invention.

Claims

1. A gas-tight piston air pump characterized by: General piston air pump including conventional structure, sealed protective cover 1 and pressure balance module; The general piston air pump comprises a motor (15), a crank, a piston ring (19), a piston, a valve plate (24) and a pump head (23); The outer end surface of the piston ring (19) is connected with the valve plate (24), and the outer end surface of the valve plate (24) is connected with the pump head (23); The sealed protective cover (1) is internally provided with a cavity for accommodating and fixing the motor (15), the output bearing of the motor (15) is provided with the crank, the crank shaft is vertically provided with a piston ring mounting hole in the sealed protective cover (1), the piston ring mounting hole is provided with a piston ring sealing bushing (18), the piston ring sealing bushing (18) is connected with the lower part of the piston ring (19), the piston ring (19), the valve plate (24) and the pump head (23) are arranged outside the sealed protective cover (1) through the piston ring sealing bushing (18), the piston is arranged in the piston ring (19), the other end of the piston connecting rod is connected with the crank, and the piston is axially reciprocated in the piston ring (19) under the driving of the crank; The piston ring sealing bushing (18) is sealingly connected with the piston ring mounting hole, the piston ring sealing bushing (18) and the piston ring (19), and the outer end surface of the piston ring (19) is sealingly connected with the inner side surface of the valve plate (24) and the outer side surface of the valve plate (24) and the lower end surface of the pump head (23). The pressure balance module comprises an on-off valve (10) which is opened and closed at the starting moment of the motor, the inlet of the on-off valve (10) is connected with the air inlet of the air pump and the inner cavity of the sealed protective cover (1) through pipelines, and the outlet of the on-off valve (10) is connected with the air outlet of the air pump through a pipeline.

2. A non-air leak piston gas pump according to claim 1, wherein, The piston ring (19) is arranged on the piston ring mounting hole through the piston ring sealing bushing (18), the piston ring sealing bushing (18) is a hollow cylinder, the outer side surface of the piston ring sealing bushing (18) is sealingly connected with the inner side surface of the piston ring mounting hole, and the lower outer side surface of the piston ring (19) is tightly and sealingly connected with the inner side surface of the piston ring sealing bushing (18).

3. A gas-tight piston gas pump according to claim 1 or 2, characterized in that The on-off valve (10) is a normally closed electromagnetic valve.

4. A gas-tight piston gas pump according to claim 1, 2 or 3, characterised in that The cavity wall of the sealed protective cover (1) is further sealingly connected with a connector socket (12), the connector socket (12) faces the outer side and is electrically connected with a connector plug (13), the power supply and control lines of the motor (15) in the inner cavity of the sealed protective cover (1) are electrically connected with the connector socket (12), and then the external power supply or control signal is electrically connected through the connector plug (13).

5. The gas pump for preventing gas leakage according to any one of claims 1 to 4, wherein The sealed protective cover (1) is further provided with a cover plate which is opened and closed to adapt to the installation of the motor (15).

6. The gas pump for preventing gas leakage according to any one of claims 1 to 5, wherein The air outlet and the air inlet of the pump head (23) are respectively connected with a high-pressure air outlet pipe (28) and a low-pressure air inlet pipe (27).

7. The gas pump for preventing gas leakage according to any one of claims 1 to 6, wherein The sealed protective cover (1) is further provided with a piston ring mounting hole, the center line of the piston ring mounting hole is parallel to or coincides with the vertical line of the crank shaft, the inner wall of the piston ring mounting hole is provided as a stepped hole which is narrow at the lower part and wide at the upper part, the piston ring sealing bushing (18) is a hollow cylinder, the outer bottom of the piston ring sealing bushing (18) is provided with a stepped groove which is wide at the lower part and narrow at the upper part, the stepped hole and the stepped groove are matched, and the outer side surface of the piston ring sealing bushing (18) is sleeved on the inner wall of the piston ring mounting hole.

8. The gas pump for preventing gas leakage according to any one of claims 1 to 7, wherein The piston ring sealing bush (18) is mounted in the piston ring mounting hole, the piston ring sealing bush (18) is mounted with the piston ring (19), the outer end surface of the piston ring (19) is sealingly connected with the inner side surface of the valve plate (24), and the outer side surface of the valve plate (24) is sealingly connected with the lower end surface of the pump head (23), the sealing connection is that at least one of the contact surfaces of any two of the above is provided with a sealing groove with an opening facing the other, and a sealing ring is filled in the sealing groove.

9. The gas pump for preventing gas leakage according to any one of claims 1 to 8, wherein The valve plate (24) of the universal piston air pump is provided with air outlet through holes and air inlet through holes penetrating the thickness of the valve plate, the upper part of the air outlet through hole is covered with an air outlet diaphragm, the lower part of the air inlet through hole is provided with an air inlet diaphragm (20), the air inlet diaphragm (20) and the air outlet diaphragm adopt a half-open design, the pump head (23) is provided with an air outlet channel and an air inlet channel, the air outlet channel is connected with the air outlet through hole on the valve plate (24), and the connecting part is further provided with an air outlet diaphragm opening and closing space, the air inlet channel is connected with the air inlet through hole on the valve plate (24), and the air outlet channel and the air inlet channel are respectively connected with the air outlet and the air inlet of the external interface.

10. An apparatus or device, characterized by The gas pump for preventing gas leakage according to any one of claims 1-9.

Images