Oil seal-containing vacuum pump capable of preventing oil leakage

Abstract

The utility model belongs to the technical field of rotary-vane vacuum pumps, and particularly relates to an oil seal-containing vacuum pump capable of preventing oil leakage. In order to overcome the defects that when an oil seal is adopted in an existing rotary-vane vacuum pump, oil leaks easily, and when other oil leakage prevention structures are adopted, the cost is high or the size is large, the technical scheme adopted by the utility model is as follows: the oil leakage prevention vacuum pump with the oil seal comprises a pump body with a pump cavity; a rotor shaft; the oil seal is used for directly or indirectly sealing the rotor shaft and the pump body; the oil return structure comprises an oil pool and an oil return channel communicated with the oil pool and the pump cavity, and the oil pool collects oil leaked from the oil seal. The oil return structure has the advantages that oil leaked out of the pump cavity returns to the pump cavity through the oil return channel under the action of negative pressure by arranging the oil return structure, and therefore the situation that the oil leaked out of the pump cavity flows to the environment outside the pump is avoided or reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of rotary vane vacuum pumps, in particular to an oil-sealed vacuum pump which prevents oil leakage. Background Art

[0002] Oil seal leakage is the most common fault of oil-sealed rotary vane vacuum pumps, and oil seal leakage has become a major problem that troubles users. When the oil seal leaks, excessive oil loss in the pump chamber will cause the vacuum pump to jam, and the leaked oil will also pollute the environment. In order to solve the oil leakage problem, a variety of solutions have emerged.

[0003] Some use shielded motor structure. However, since the air gap between the motor rotor and the shielding sleeve is 0.5-1mm, such a small gap may cause damage to the shielding sleeve if the shielding sleeve is made of a material that is easy to deform. The shielding sleeve made of stainless steel has the phenomenon of electromagnetic eddy current heating, and the gap between the motor rotor and the stator is large, which reduces the efficiency of the motor. In addition, the cost of shielded motors is also high.

[0004] Some use magnetic couplings and use nylon or stainless steel shielding sleeves to wrap the pump shaft for sealing. The drive of the magnetic coupling drives the inner ring to rotate through the rotation of the magnetic field of the outer ring. Since this type of magnetic coupling is a highly customized product, the cost is generally high. Magnetic couplings also have problems such as large size and demagnetization.

[0005] Some other motor structures use glue-filled motors, which seal the motors by filling them with glue. This type of process requires special glue-filling equipment to achieve mass production, and the cost of the glue is also high.

[0006] The above ideas for solving oil leakage are to prevent oil from flowing out of the pump cavity. However, the applicant has found that even if oil flows out of the pump cavity due to oil seal leakage, as long as all or most of the flowing oil can be recovered into the pump cavity in time, the same or substantially the same effect can be achieved. Summary of the invention

[0007] The utility model aims at the disadvantages that the existing rotary vane vacuum pump is prone to oil leakage when using oil seals, and other anti-oil leakage structures are either high in cost or large in size. The utility model provides an oil-leakage-proof vacuum pump containing an oil seal, which still uses an oil seal, but is provided with an oil return structure. When the oil seal leaks, the leaked oil is returned to the pump chamber through the oil return structure, thereby achieving low-cost and reliable oil-proof (the "oil-proof" in the solution of the utility model does not mean that the oil will not leak from the pump chamber where the rotary vane is installed through the oil seal, but means that the leaked oil will completely or basically not flow out to the environment).

[0008] To achieve the above purpose, the utility model adopts the following technical solution: an oil-leakage-proof oil-sealed vacuum pump, the oil-leakage-proof oil-sealed vacuum pump comprising:

[0009] The pump body has a pump chamber;

[0010] The rotor shaft is partially located in the pump chamber and partially outside the pump chamber;

[0011] The oil seal directly or indirectly seals between the rotor shaft and the pump body;

[0012] The oil return structure includes an oil sump and an oil return passage connecting the oil sump and the pump chamber. The oil sump collects the oil leaked from the oil seal.

[0013] The oil - leakage - proof oil - seal - containing vacuum pump of the present utility model adds an oil return structure on the basis of the existing vacuum pump with an oil seal. The oil return structure includes an oil sump for collecting the oil leaked from the oil seal and an oil return passage connecting the oil sump and the pump chamber. During the working process, the air pressure in the pump chamber is lower than the external atmospheric pressure, and the oil in the oil sump returns to the pump chamber through the oil return passage under the action of negative pressure, thereby avoiding or reducing the oil flowing into the external environment of the pump. The structure and installation structure of the oil seal can refer to the prior art. In the non - working state, the oil in the pump chamber basically does not flow out.

[0014] As an improvement, the oil return structure further includes a one - way valve that allows oil to flow only from the oil sump to the pump chamber.

[0015] As an improvement, the one - way valve is located at the end of the oil return passage close to the pump chamber to reduce the oil in the oil return passage.

[0016] As an improvement, the oil sump is adjacent to the oil seal.

[0017] As an improvement, the oil sump includes a collection part located below the oil seal; the oil return passage communicates with the bottom of the oil sump.

[0018] As an improvement, the oil return passage communicates with the bottom of the pump chamber.

[0019] As an improvement, the oil return passage is directly formed on the pump body.

[0020] As an improvement, the oil return passage includes a first section in the height direction adjacent to the oil sump, a second section in the height direction adjacent to the pump chamber, and a third section in the horizontal direction connecting the first section and the second section.

[0021] As an improvement, the lower end of the first section penetrates, the lower end of the third section penetrates, and at least one end of the second section penetrates.

[0022] As an improvement, the oil return passage includes an oil return pipe exposed outside the pump body.

[0023] As an improvement, both ends of the oil return pipe are detachably connected to the oil sump and the pump body respectively. The oil return pipe includes connectors at both ends and an intermediate pipe.

[0024] As an improvement, part or all of the oil return structure is detachable from the pump body.

[0025] As an improvement, the oil-sealed vacuum pump with oil leakage prevention is a single-stage pump or a two-stage pump.

[0026] As an improvement, the oil-sealed vacuum pump with oil leakage prevention is a rotary vane vacuum pump, and one or more rotary vanes are provided on the rotor shaft of the oil-sealed vacuum pump with oil leakage prevention.

[0027] As an improvement, the oil-sealed vacuum pump with oil leakage prevention is a sliding vane vacuum pump.

[0028] As an improvement, part or all of the oil return structure is detachable from the pump body.

[0029] The beneficial effects of the oil-sealed vacuum pump with oil leakage prevention of the present utility model are as follows: On the basis of the existing vacuum pump with oil seal, an oil return structure is added. The oil return structure includes an oil pool for collecting the oil leaked from the oil seal and an oil return channel connecting the oil pool and the pump cavity. During the working process, even if the oil seal leaks oil, due to the air pressure in the pump cavity being much lower than the external atmospheric pressure, the oil leaked from the oil seal converges into the oil pool, and then the oil in the oil pool returns to the pump cavity through the oil return channel under the action of negative pressure, thereby avoiding or reducing the oil flowing into the external environment of the pump. Description of the Drawings

[0030] Figure 1 is a schematic structural diagram of the oil-sealed vacuum pump with oil leakage prevention in Embodiment 1 of the present utility model.

[0031] Figure 2 is a schematic structural diagram of the oil-sealed vacuum pump with oil leakage prevention in Embodiment 2 of the present utility model.

[0032] In the figure, 1. Pump body; 11. Pump cavity;

[0033] 2. Oil seal;

[0034] 3. Oil pool;

[0035] 4. Oil return channel;

[0036] 5. Check valve. Detailed Embodiments

[0037] The technical solutions of the embodiments of the present invention will be explained and described below. However, the following embodiments are only the preferred embodiments of the present invention and not all of them. Based on the embodiments in the embodiments, other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present invention.

[0038] See Figure 1 and Figure 2, an oil - leakage - proof oil - sealed vacuum pump, the oil - leakage - proof oil - sealed vacuum pump comprising:

[0039] A pump body having a pump cavity;

[0040] A rotor shaft, partially located in the pump cavity and partially outside the pump cavity;

[0041] An oil seal that directly or indirectly seals between the rotor shaft and the pump body;

[0042] An oil return structure, including an oil sump and an oil return passage connecting the oil sump and the pump cavity, the oil sump collecting the oil leaked from the oil seal.

[0043] For the oil - leakage - proof oil - sealed vacuum pump of the present utility model, an oil return structure is added on the basis of the existing rotary vane vacuum pump with an oil seal. The oil return structure includes an oil sump for collecting the oil leaked from the oil seal and an oil return passage connecting the oil sump and the pump cavity. During the working process, the air pressure in the pump cavity is lower than the external atmospheric pressure, and the oil in the oil sump returns to the pump cavity through the oil return passage under the action of negative pressure, thereby avoiding or reducing the flow of oil to the external environment of the pump. The structure and installation structure of the oil seal can refer to the prior art.

[0044] Embodiment 1

[0045] See Figure 1 , for the oil - leakage - proof oil - sealed vacuum pump of Embodiment 1 of the present utility model, the oil - leakage - proof oil - sealed vacuum pump is a rotary vane vacuum pump, and the oil - leakage - proof oil - sealed vacuum pump comprises:

[0046] A pump body 1 having a pump cavity 11;

[0047] A pump rotor provided in the pump cavity 11;

[0048] A rotary vane provided on the pump rotor;

[0049] An oil seal 2;

[0050] An oil return structure, including an oil sump 3 and an oil return passage 4 connecting the oil sump 3 and the pump cavity 11, the oil sump 3 collecting the oil leaked from the oil seal 2.

[0051] In this embodiment, the pump cavity 11 of the pump body 1 is divided into two communicating cavities. In other embodiments, the pump cavity 11 can be one cavity.

[0052] In this embodiment, the oil sump 3 is adjacent to the oil seal 2, so as to better collect the leaked oil and reduce the exposure time of the leaked oil.

[0053] In this embodiment, the oil sump 3 includes a collecting portion located below the oil seal 2. The oil sump 3 can have an open portion that is larger at the top and smaller at the bottom.

[0054] In other embodiments, the oil sump 3 may further have a dust-proof portion located above the oil seal 2.

[0055] In this embodiment, the oil return passage 4 communicates with the bottom of the oil sump 3.

[0056] In this embodiment, the oil return passage 4 communicates with the bottom of the pump chamber 11.

[0057] In other embodiments, the oil return passage 4 may also communicate with other positions of the pump chamber 11.

[0058] In this embodiment, the oil return structure further includes a check valve 5 that allows oil to flow only from the oil sump 3 to the pump chamber 11, so as to prevent the oil in the pump chamber 11 from flowing out to the oil sump 3 via the oil return passage 4.

[0059] In this embodiment, the check valve 5 is located at the end of the oil return passage 4 close to the pump chamber 11.

[0060] In other embodiments, in order to prevent dust and impurities from being sucked into the pump chamber 11, the oil return structure may further include a filter provided on the oil return passage 4.

[0061] In this embodiment, the oil return structure is detachable from the pump body 1. Thus, when the working environment is relatively good, the oil return structure can be removed.

[0062] In this embodiment, the oil return passage 4 includes an oil return pipe exposed outside the pump body 1.

[0063] In this embodiment, both ends of the oil return pipe are detachably connected to the oil sump 3 and the pump body 1 respectively. The oil return pipe includes connectors at both ends and an intermediate pipe, which is convenient for cleaning and maintenance.

[0064] In this embodiment, the oil-sealed vacuum pump with oil leakage prevention is a two-stage pump, that is, there are two axially distributed and connected chambers. In other embodiments, the oil-sealed vacuum pump with oil leakage prevention may also be a single-stage pump or a three-stage pump, etc.

[0065] In this embodiment, one or more of the rotating vanes are provided on the pump rotor of the oil-sealed vacuum pump with oil leakage prevention.

[0066] In other embodiments, the vacuum pump may also be a sliding vane vacuum pump.

[0067] The beneficial effects of the oil leakage prevention oil-sealed vacuum pump according to the first embodiment of the present utility model are as follows: On the basis of the existing rotary vane vacuum pump using an oil seal 2, an oil return structure is added. The oil return structure includes an oil sump 3 for collecting the oil leaked from the oil seal 2 and an oil return passage 4 connecting the oil sump 3 and the pump chamber 11. During the working process, even if the oil seal 2 leaks oil, due to the air pressure in the pump chamber 11 being much lower than the external atmospheric pressure, the oil leaked from the oil seal 2 gathers in the oil sump 3, and then the oil in the oil sump 3 returns to the pump chamber 11 through the oil return passage 4 under the action of negative pressure, thereby avoiding or reducing the oil from flowing into the external environment of the pump; The oil return structure includes a check valve 5, which can prevent the oil in the pump chamber 11 from flowing out to the oil sump 3 through the oil return passage 4; The oil return structure is detachable from the pump body 1, which is convenient for maintenance and cleaning. When the working environment is excellent and there is no need for oil return, the oil return structure can be removed.

[0068] Embodiment 2

[0069] See Figure 2 In this embodiment, the oil return passage 4 is directly formed on the pump body 1.

[0070] In this embodiment, the oil return passage 4 includes a first section in the height direction adjacent to the oil sump 3, a second section in the height direction adjacent to the pump chamber 11, and a third section in the horizontal direction connecting the first section and the second section. The lower end of the first section penetrates, the lower end of the third section penetrates, and both ends of the second section penetrate.

[0071] In this embodiment, the oil return passage 4 can be formed by drilling holes. The hole of the first section is a through hole, the hole of the second section is a through hole, and the hole of the third section is a through hole. The outer ends of each hole can be sealed by a sealing plug or the like.

[0072] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the content described in the above specific implementation manner. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. Anti-leakage oil-sealed vacuum pump, characterized by: The oil-leakage-proof oil-sealed vacuum pump comprises: A pump body (1) having a pump chamber (11); a rotor shaft, partly located in the pump chamber (11) and partly located outside the pump chamber (11); An oil seal (2) directly or indirectly seals the rotor shaft and the pump body (1); The oil return structure comprises an oil pool (3) and an oil return passage (4) communicating with the oil pool (3) and the pump chamber (11); the oil pool (3) collects oil leaking from the oil seal (2).

2. The oil-sealed vacuum pump for preventing oil leakage according to claim 1, characterized in that: The oil return structure also includes a one-way valve (5) that allows oil to flow only from the oil pool (3) to the pump chamber (11).

3. The oil-sealed vacuum pump for preventing oil leakage according to claim 2, characterized in that: The one-way valve (5) is located at an end of the oil return channel (4) close to one end of the pump chamber (11).

4. The oil-sealed vacuum pump for preventing oil leakage according to claim 1, characterized in that: The oil pool (3) comprises a collecting portion located below the oil seal (2); the oil return channel (4) is connected to the bottom of the oil pool (3).

5. The oil-sealed vacuum pump with oil leakage prevention according to claim 1, characterized in that: The oil return channel (4) is partially or entirely formed directly on the pump body (1).

6. The oil-sealed vacuum pump for preventing oil leakage according to claim 5, characterized in that: The oil return passage (4) comprises a first section in the height direction adjacent to the oil pool (3), a second section in the height direction adjacent to the pump chamber (11), and a third section connecting the first section and the second section.

7. The oil-sealed vacuum pump for preventing oil leakage according to claim 6, characterized in that: The lower end of the first section penetrates, the lower end of the third section penetrates, and at least one end of the second section penetrates.

8. The oil-sealed vacuum pump with oil leakage prevention according to claim 1, characterized in that: The oil return passage (4) comprises an oil return pipeline exposed outside the pump body (1).

9. The oil-sealed vacuum pump with oil leakage prevention according to claim 8, characterized in that: The two ends of the oil return pipeline are detachably connected to the oil pool (3) and the pump body (1), respectively, and the oil return pipeline comprises joints at both ends and an intermediate pipeline.

10. The oil-leakage-proof oil-sealed vacuum pump according to claim 1, characterized in that: The oil-leakage-proof oil-sealed vacuum pump is a single-stage pump or a two-stage pump; The oil-leakage-proof oil-sealed vacuum pump is a rotary vane vacuum pump, and one or more rotary vanes are arranged on the rotor shaft of the oil-leakage-proof oil-sealed vacuum pump, or the oil-leakage-proof oil-sealed vacuum pump is a sliding valve vacuum pump; Part or all of the oil return structure is detachable from the pump body (1).

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