Miniature vacuum pump

Abstract

The present invention provides a mini vacuum pump, comprising: a pump body provided with a fluid outlet and at least comprising a cover, the cover being an integral seamless member and having an exposed fluid inlet formed therein, the inner side end face of the cover having a communication port formed therein for fluid communication with the fluid inlet; the pumping component is installed in the pump body, a pump cavity is formed by the pumping component or / and the pump body, the fluid inlet is in fluid communication with the pump cavity and forms an inflow path, the pump cavity is in fluid communication with the fluid outlet and forms an outflow path, and the communication port is located in the inflow path; the driving component is in transmission connection with the pumping component so as to drive the pumping component to move; the check valve is arranged in the pump body and is adjacent to the communicating port, and when the miniature vacuum pump does not work, the check valve closes the communicating port; when the miniature vacuum pump works, the check valve opens the communication port.

Description

Technical Field

[0001] The present invention relates to the technical field of microfluidic devices, and particularly to a micro vacuum pump. Background Art

[0002] A micro vacuum pump is a miniaturized vacuum generating device that can generate, maintain, or improve a vacuum environment in a closed space. This type of pump has the advantages of small size and compact structure, and is suitable for scenarios with low flow rate and low vacuum degree, and is commonly found in medical, scientific research, industrial and other fields.

[0003] Currently, the micro vacuum pumps on the market at least include two categories: diaphragm pumps and piston pumps. Among them, diaphragm pumps use the reciprocating motion of an elastic diaphragm to change the volume of the pump chamber, have an oil-free design and high cleanliness, and are commonly used in medical equipment; piston pumps pump air through the movement of a piston, have a relatively high pumping speed but slightly louder noise, and are suitable for industrial automation.

[0004] However, regardless of which type of micro vacuum pump on the market, there is a technical problem that after stopping working, the vacuum degree in the closed space slowly decreases. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a new type of micro vacuum pump.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A micro vacuum pump, comprising: a pump body, provided with a fluid outlet and at least including a cover, the cover being an integrally seamless member and formed with a fluid inlet exposed to the outside, and an inner end face of the cover being formed with a communication port fluidly connecting the fluid inlet; a pumping component, installed inside the pump body, the pumping component or / and the pump body forming a pump chamber, the fluid inlet fluidly connecting to the pump chamber to form an inflow path, the pump chamber fluidly connecting to the fluid outlet to form an outflow path, and the communication port being located on the inflow path; a driving component, drivingly connected to the pumping component to drive the pumping component to move; and a check valve, configured inside the pump body and adjacent to the communication port, the check valve closing the communication port when the micro vacuum pump is not working; and the check valve opening the communication port when the micro vacuum pump is working.

[0007] In the above technical solution, preferably, the check valve is a flap valve, the check valve includes a valve stem portion fixedly installed on the cover and a deformable valve face portion, and when the micro vacuum pump is not working, the valve face portion maintains a state of closing the communication port.

[0008] In the above technical solution, preferably, the check valve includes a valve body adapted to the communication port and a spring fixedly arranged in the pump body, and the spring abuts against the valve body and applies a force towards the valve body to the communication port.

[0009] In the above technical solution, preferably, the check valve is composed of a multi-lobe elastic structure fixedly installed on the cover and capable of closing. When the micro vacuum pump is not working, the multi-lobe elastic structure is closed and maintains the state of closing the communication port.

[0010] In the above technical solution, preferably, a convex post is formed at the inner end of the cover, the communication port is opened on the side wall of the convex post, the check valve is an annular diaphragm body, and the diaphragm body is installed outside the convex post and includes a top fixedly arranged on the cover and a bottom inclined towards the convex post relative to the top; when the micro vacuum pump is not working, the bottom contacts the outer wall of the convex post and maintains the state of closing the communication port.

[0011] In the above technical solution, preferably, the micro vacuum pump is a diaphragm vacuum pump, and the micro vacuum pump further includes a valve seat, a diaphragm seat and a motor seat arranged in sequence along the axial direction. The check valve is clamped between the cover and the valve seat, and the pumping component is installed on the diaphragm seat. Further preferably, the cover has a protrusion located in the communication port. The check valve includes an installation part clamped by the cover and the valve seat, a deformable part located inside the installation part, and a ventilation hole opened on the deformable part and adapted to the protrusion. The ventilation hole is located on the inflow path; when the micro vacuum pump is not working, the ventilation hole contacts the protrusion and the check valve maintains the state of closing the communication port.

[0012] In the above preferred solution, further preferably, the valve seat is provided with a convex ring and a through hole located inside the convex ring. The through hole is located on the inflow path, and the check valve is installed on the convex ring and forms a buffer cavity with the convex ring.

[0013] In the above preferred solution, further preferably, the inner surface of the cover has a convex lip facing the valve seat, and the convex lip is located outside the convex ring and presses against the check valve.

[0014] Through research, it is found that after the micro vacuum pump stops working, the external fluid will enter the pump body through the gap on the pump body under the action of the pressure difference and flow back to the fluid inlet, resulting in the technical problem that the vacuum degree of the sealed space connected to the fluid inlet slowly decreases after the vacuum pump stops working. Therefore, the micro vacuum pump provided by the present invention includes a cover provided with a communication port and a check valve that can close the communication port. The cover is an integral seamless component. After its communication port is closed, the fluid cannot penetrate into the interior of the cover from other positions of the cover and flow back to the fluid outlet, thus solving the above technical problem. Description of the Drawings

[0015] Figure 1 The micro vacuum pump according to the first embodiment provided by the present invention;

[0016] Figure 2 An example of a possible check valve provided by the present invention;

[0017] Figure 3 The micro vacuum pump according to the second embodiment provided by the present invention;

[0018] Figure 4 is Figure 3 The sectional view of the provided micro vacuum pump;

[0019] Figure 5 is Figure 4 The partial enlarged view of;

[0020] Figure 6 is Figure 3 The three-dimensional Figure 1 ;

[0021] Figure 7 is Figure 6 The three-dimensional Figure 2 ;

[0022] Figure 8 is Figure 3 The three-dimensional of the valve seat of the provided micro vacuum pump Figure 1 ;

[0023] Figure 9 is Figure 8 The three-dimensional of the provided valve seat Figure 2 ;

[0024] Figure 10 is Figure 3 The three-dimensional view of the diaphragm integral part of the provided micro vacuum pump;

[0025] Figure 11 is Figure 3 The three-dimensional view of the pumping component of the provided micro vacuum pump;

[0026] Figure 12 For Figure 3 The perspective view of the diaphragm seat of the provided micro vacuum pump.

[0027] Annotations in the figure:

[0028] 100, micro vacuum pump; 200, micro vacuum pump;

[0029] 1, pump body; 11, cover; 111, fluid inlet; 112, communication port; 113, convex post; 114, air inlet nozzle; 115, protrusion; 116, air outlet groove;

[0030] 12, fluid outlet;

[0031] 13, valve seat; 131, first through hole; 132, exhaust hole; 133, installation groove; 134, convex ring; 135, buffer cavity; 136, bowl-shaped groove; 137, air inlet groove;

[0032] 14, diaphragm seat; 141, installation hole; 142, third through hole; 143, fourth through hole;

[0033] 15, motor seat, 151, transmission cavity;

[0034] 2, pumping component; 21, pump cavity; 22, bellows; 23, skirt; 24, second through hole; 25, inlet check valve;

[0035] 3, driving component;

[0036] 4, check valve; 41, umbrella handle part; 42, umbrella face part; 43, valve body; 44, spring; 45, installation part; 46, deformable part; 47, ventilation hole;

[0037] 5, diaphragm integrated part; 51, outlet check valve;

[0038] 6, transmission component. Specific embodiments

[0039] To describe in detail the technical content, structural features, achieved objectives and effects of this application, the following will describe the technical solutions in the embodiments of this application in combination with the accompanying drawings in the embodiments of this application.

[0040] In this application, spatial relative terms such as "under", "below", "beneath", "lower", "above", "upper", "on", "higher", "side" (e.g., as in "side wall") are used to describe the relationship between one element and another (other) element as shown in the drawings. The spatial relative terms are intended to include different orientations of the device in addition to the orientation depicted in the drawings during use, operation, and / or manufacturing. For example, if the device in the drawings is flipped, an element described as "under" or "beneath" another element or feature will then be positioned "above" the other element or feature. Thus, the exemplary term "under" can include both the upper and lower orientations. Additionally, the device can be positioned otherwise (e.g., rotated 90 degrees or at other orientations), and accordingly, the spatial relative descriptors used herein are to be interpreted.

[0041] In this application, the term "fluid communication" used to express the relative relationship between two fluid spaces (such as a cavity, a flow channel, a hole) means that there is a fluid path for fluid to flow from one fluid space to another between the two fluid spaces, and the two fluid spaces can be directly connected or can be connected through several fluid spaces.

[0042] In this application, unless otherwise specified, the term "axial direction" means the direction of the axis of the micro vacuum pump.

[0043] The present invention provides a micro vacuum pump, aiming to solve the technical problem that the vacuum degree of the closed space connected thereto slowly decreases after the existing vacuum pumps of this type stop working. To facilitate the description of the technical solution provided by the present invention, the general structure of the micro vacuum pump 100 and related technical problems will be introduced below first.

[0044] Specifically, referring to Figure 1 , it schematically shows the micro vacuum pump 100 of the first embodiment provided by the present invention. The micro vacuum pump 100 includes a pump body 1, a pumping component 2 disposed inside the pump body 1 and used for pumping fluid, and a driving component 3 used for driving the pumping component 2. It should be noted here that the check valve and its related technical solutions provided by the present invention can undoubtedly be applied to diaphragm-type, electromagnetic-type, piston-type, etc. (the main differences between the above various micro pumps lie in the types of the pumping component and the driving component) micro vacuum pumps. Therefore, the specific type of the micro vacuum pump does not limit the protection scope of the present invention.

[0045] The pump body 1 at least includes a cover 11, on which a fluid inlet 111 for fluid to enter the pump body 1 is formed, and the fluid inlet 111 is exposed to the outside. A pumping component 2 is arranged inside the pump body 1, and a pump chamber 21 is formed inside the pumping component 2 or between the pumping component 2 and the pump body 1. A fluid outlet 12 for fluid to leave the pump body 1 is formed on the pump body 1. The fluid inlet 111 is in fluid communication with the pump chamber 21 to form an inflow path (not marked in the figure), and the pump chamber 21 is in fluid communication with the fluid outlet 12 to form an outflow path (not marked in the figure). Generally, a number of one-way valves ( Figure 1 not shown) for restricting the one-way movement of fluid are arranged on the above-mentioned inflow path, outflow path or / and pump chamber, and this one-way valve is different from the check valve 4 provided by the present invention (see below).

[0046] The fluid inlet 111 of the micro vacuum pump 100 is usually hermetically connected to an evacuated object (such as an airbag) with a closed space. When the micro vacuum pump 100 is working, the driving component 3 drives the pumping component 2 to move, causing the fluid pressure in the pump chamber 21 to change periodically. Under the action of the above-mentioned periodic pressure change, the fluid in the closed space enters the pump chamber 21 via the inflow path, and then reaches the fluid outlet 12 via the outflow path and is discharged to the outside from the fluid outlet 12.

[0047] After the micro vacuum pump 100 stops working, the above-mentioned closed space should maintain a certain vacuum degree unchanged. However, in fact, the pump body 1 of the micro vacuum pump 100 does not have good airtightness, and there are certain gaps between the various components of the pump body 1 (such as the cover 11 and the valve seat 13 below), the connection between the pump body 1 and the driving component 3, and the bolt holes on the pump body 1. Under the action of the fluid pressure difference between the external environment and the closed space, the external fluid will enter the inside of the pump body 1 via the above-mentioned gaps, and finally enter the closed space from the fluid inlet 111 of the pump body 1. In addition, there is a certain pressure difference between the fluid inlet 111, the pump chamber 21, and the fluid outlet 12. Under the action of this pressure difference, the one-way valve of the micro vacuum pump 100 often fails to close tightly, and the fluid flows back from the pump chamber 21 or the fluid outlet 12 to the fluid inlet 111. Therefore, this type of micro vacuum pump has the technical problem that the vacuum degree of the connected closed space slowly decreases after stopping working.

[0048] To this end, the present invention further provides a check valve 4 disposed in the pump body 1. An inner end surface of the cover 11 is provided with a communication port 112 that fluidly communicates with the fluid inlet 111, and this communication port 112 is located on the inflow path of the pump body 1. The check valve 4 is disposed adjacent to the communication port 112 and is configured to close the above-mentioned communication port 112 when the micro vacuum pump 100 is not operating, so as to cut off the fluid communication between the fluid inlet 111 and the inside of the pump body 1 (including the pump chamber 21); the check valve 4 is simultaneously configured to open the above-mentioned communication port 112 when the micro vacuum pump 100 is operating, so as to allow fluid communication between the fluid inlet 111 and the inside of the pump body 1.

[0049] The cover 11 is an integrally seamless member, that is, the cover 11 is an integral member that is manufactured by one or more processes such as turning, die casting, casting, thermoforming, etc., and is non-separable and has no mating clearance. It can be understood that except for the communication port 112, external fluid cannot penetrate into the inside of the cover 11 through other positions of the cover 11 and flow to the fluid outlet 12.

[0050] When the micro vacuum pump 100 provided by the present invention stops operating, the check valve 4 can close the communication port 112 of the cover 11. Since the cover 11 is an integrally seamless member, the fluid outside and / or inside the pump body 1 cannot flow back to the fluid inlet 111, thereby solving the technical problem that the vacuum degree of the connected closed space will slowly decrease after the traditional micro vacuum pump stops operating.

[0051] Figure 2 Several possible examples of the check valve 4 provided by the present invention are shown. For ease of description, hereinafter, English letter markings will be added after the components that appear repeatedly in the appendix Figure 2 to distinguish each example.

[0052] As Figure 2 (a) shows, the check valve 4a provided is an umbrella valve, and this umbrella valve includes an umbrella handle portion 41 fixedly installed on the cover 11 and a deformable umbrella surface portion 42. When the micro vacuum pump 100 is not operating, the umbrella surface portion 42 of the check valve 4a maintains the state of closing the communication port 112a under the action of its own elastic force or / and the pressure difference on both sides; when the micro vacuum pump 100 is operating, a fluid pressure difference is generated between the fluid inlet 111 and the pump chamber 21, and under the action of this pressure difference, the fluid overcomes the elastic force of the umbrella surface portion 42 of the check valve 4a and flows towards the pump chamber 21.

[0053] As Figure 2As shown in (b), the check valve 4b provided therein includes a valve body 43 adapted to communicate with the communication port 112b and a spring 44 fixedly installed inside the pump body 1. The spring 44 abuts against the valve body 43 and applies a force towards the communication port 112b to the valve body 43. When the micro vacuum pump 100 is not operating, the valve body 43 of the check valve 4b maintains the state of closing the communication port 112b under the action of the spring 44; when the micro vacuum pump 100 is operating, a fluid pressure difference is generated between the fluid inlet 111 and the pump chamber 21. Under the action of this pressure difference, the fluid overcomes the elastic force of the spring 44 and flows towards the pump chamber 21.

[0054] As Figure 2 As shown in (c), the check valve 4c provided therein is composed of a multi-lobe elastic structure fixedly installed on the inner end face of the cover 11 and capable of closing. When the micro vacuum pump 100 is not operating, the check valve 4c closes under the action of its own elastic force or / and the pressure difference on both sides (the closed state is as shown in the figure) and maintains the state of closing the communication port 112c; when the micro vacuum pump 100 is operating, a fluid pressure difference is generated between the fluid inlet 111 and the pump chamber 21. Under the action of this pressure difference, the fluid overcomes the elastic force of the check valve 4c and flows towards the pump chamber 21.

[0055] As Figure 2 As shown in (d), the inner end portion of the cover 11 has a convex column 113, and the communication port 112d is opened on the side wall of the convex column 113. Figure 2 The check valve 4d provided in (d) is an annular diaphragm body with an open bottom. The diaphragm body includes a top (not marked in the figure) fixedly installed on the inner end face of the cover 11 and a bottom (not marked in the figure) close to the bottom opening and inclined towards the convex column 113 relative to the top. When the micro vacuum pump 100 is not operating, the check valve 4d, under the action of its own elastic force or / and the pressure difference on both sides, has its bottom closely attached to the outer side wall of the convex column 113 and maintains the state of closing the communication port 112d; when the micro vacuum pump 100 is operating, a pressure difference is formed between the fluid inlet 111 and the pump chamber 21. Under the action of this pressure difference, the fluid overcomes the elastic force of the check valve 4d and flows towards the pump chamber 21.

[0056] Referring to Figure 3-4 , a micro vacuum pump 200 is shown, which is an embodiment of the specific application of the micro vacuum pump 100 in the first embodiment provided by the present invention on a diaphragm micro pump. To avoid repetition, the structural bodies with the same functions will not be described again, and the markings of the previous embodiment will continue to be used.

[0057] The pump body 1 of the micro vacuum pump 200 includes a cover 11, a valve seat 13, a diaphragm seat 14 capable of carrying a pumping component 2, and a motor seat 15 providing a connection basis for a driving component 3, which are arranged axially in sequence. The cover 11, the valve seat 13, the diaphragm seat 14, and the motor seat 15 are firmly fixed together by a number of fastening bolts (not marked in the figure).

[0058] Combined with Figure 6-7 , an air inlet nozzle 114 is provided on the cover 11. The fluid inlet 111 is formed on the outer end of the air inlet nozzle 114, and the fluid outlet 12 is directly opened on the cover 11. The cover 11 also forms a communication port 112 on the inner end surface, a protrusion 115 fixedly arranged in the communication port 112, and a pair of air outlet grooves 116 that fluidly communicate with the fluid outlet 12.

[0059] Refer to Figure 5 and Figure 10 , the check valve 4 provided in this embodiment is integrated on a diaphragm integrated part 5, and the diaphragm integrated part 5 is clamped between the cover 11 and the valve seat 13. The check valve 4 has a mounting portion 45 for being clamped by the cover 11 and the valve seat 13, a deformable portion 46 that can be elastically deformed, and a ventilation hole 47 opened on the deformable portion 46. The ventilation hole 47 is located on the inflow path of the micro vacuum pump 200 and is configured to fit the shape of the protrusion 115 on the cover 11. When the micro vacuum pump 200 stops working, the ventilation hole 47 abuts against the protrusion 115 (as Figure 5 ), thereby closing the communication port 112 by the check valve 4; when the micro vacuum pump 200 is working, a pressure difference is formed between the fluid inlet 111 and the pump chamber 21. Under the action of this pressure difference, the deformable portion 46 of the check valve 4 deforms in the direction of the valve seat 13, the ventilation hole 47 leaves the protrusion 115 on the cover 11, and the fluid flows to the pump chamber 21 through the ventilation hole 47.

[0060] The diaphragm integrated part 5 also includes a pair of outlet check valves 51. Each outlet check valve 51 is located on the outflow path of the micro vacuum pump 200 and axially aligns with a pair of air outlet grooves 116 of the cover 11 respectively.

[0061] Combined with Figure 8-9 , a first through hole 131 located on the inflow path and a pair of exhaust holes 132 located on the outflow path are opened on the valve seat 13. The pair of exhaust holes 132 axially align with a pair of outlet valves 51 of the diaphragm integrated part 5 respectively.

[0062] Further, an installation groove 133 adapted to the diaphragm integrated part 5 and a convex ring 134 protruding towards the cover 11 are formed on the side end surface of the valve seat 13 facing the cover 11. The first through hole 131 is located inside the convex ring 134. The mounting portion 45 of the check valve 4 is clamped between the convex ring 134 and the inner wall of the communication port 112. Still further, a convex lip 117 located outside the communication port 112 is formed on the inner end surface of the cover 11. The convex lip 117 extends towards the diaphragm integrated part 5 to improve the airtightness of the check valve 4.

[0063] With the above settings, a buffer chamber 135 located inside the convex ring 134 is formed between the check valve 4 and the convex ring 134. When the micro vacuum pump 200 operates, the air wave sound wave formed by the periodic flapping of the inlet check valve 25 (see below) propagates along the inflow path in the direction of the fluid inlet 111. The air wave sound wave reaches the buffer chamber 135 via the first through hole 131, and the amplitude in the buffer chamber 135 is greatly reduced after pressure reduction and multiple emissions. Then, the air wave sound wave enters the communication port 112 via the vent hole 47 on the check valve 4 and is depressurized again. Thus, the amplitude of the air wave sound wave when it reaches the fluid inlet 111 can be greatly reduced, thereby achieving the technical effect of noise reduction and silencing.

[0064] Continue to refer to Figure 9 and 11 , the pumping component 2 of the micro vacuum pump 200 is a diaphragm component, which is clamped between the diaphragm seat 15 and the valve seat 13. The pumping component 2 has a number of bellows 22, a skirt 23 connecting the bellows 22 together, a second through hole 24 opened on the skirt 23, and a number of inlet check valves 25 provided on the skirt 23. The second through hole 24 is axially aligned with the first through hole 131. On the end face of the valve seat 13 facing the pumping component 2, a number of bowl-shaped grooves 136 adapted to the bellows 22 and a number of air inlet grooves 137 respectively communicating with the bowl-shaped grooves 136 are formed. One end of each air inlet groove 137 is axially aligned with each inlet check valve 25 respectively. The exhaust hole 132 of the valve seat 13 is exposed from the bowl-shaped groove 136. It can be understood that the exhaust hole 132, the air outlet groove 116, and the fluid outlet 12 are sequentially communicated and constitute the outflow path of the micro vacuum pump 200. The outlet check valve 51 is located between the exhaust hole 132 and the air outlet groove 116 to limit the one-way movement of the fluid.

[0065] Combined with Figure 12 , on the diaphragm seat 14, mounting holes 141 for placing the bellows 22 respectively, a third through hole 142 fluidly communicating with the transmission cavity 151 (see below), and a number of fourth through holes 143 fluidly communicating with the transmission cavity 151 are provided. The mounting holes 141, the third through hole 142, and each fourth through hole 143 axially penetrate the diaphragm seat 14. The third through hole 142 and the fourth through hole 143 are axially aligned with the second through hole 24 and the inlet check valve 25 respectively. It can be understood that the fluid inlet 111, the communication port 112, the vent hole 47, the first through hole 131, the second through hole 24, the third through hole 142, the transmission cavity 151, the fourth through hole 143, and the air inlet groove 137 are sequentially communicated and constitute the inflow path of the micro vacuum pump 200. The inlet check valve 25 is located between the fourth through hole 143 and the air inlet groove 137 to restrict the one-way movement of the fluid.

[0066] Continue to refer to Figure 3-4, the motor base 15 defines a transmission cavity 151 with an upper opening, and the diaphragm base 14 closes the upper opening of the transmission cavity 151. The micro vacuum pump 200 further includes a transmission component 6 disposed in the transmission cavity 151, and the transmission component 6 is used to realize the transmission connection between the driving component 3 and the pumping component 2.

[0067] The driving component 3 of the micro vacuum pump 200 is an electric motor, which has a motor housing (not marked in the figure) and an output shaft protruding outward relative to the motor housing (not marked in the figure). The bottom of the motor base 15 is provided with a shaft hole (not marked in the figure) for the output shaft to pass through and a plurality of bolt holes (not marked in the figure) for fastening bolts to pass through. The fastening bolts pass through the bolt holes and are threadedly connected to the motor housing to fix the driving component 3 on the motor base 15. The output shaft of the driving component 3 passes through the shaft hole and is connected to the transmission component 6.

[0068] The above embodiments are only for illustrating the technical concept and features of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it accordingly. It should not be used to limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit of the present application should be covered within the protection scope of the present application.

Claims

1. A micro vacuum pump, characterized in that, Comprising: A pump body, provided with a fluid outlet and at least including a cover, the cover being an integrally seamless member and formed with a fluid inlet exposed to the outside, and an inner end face of the cover being formed with a communication port fluidly connecting the fluid inlet; A pumping component, installed inside the pump body, the pumping component or / and the pump body forming a pump chamber, the fluid inlet fluidly connecting to the pump chamber to form an inflow path, the pump chamber fluidly connecting to the fluid outlet to form an outflow path, and the communication port being located on the inflow path; A driving component, drivingly connected to the pumping component to drive the pumping component to move; And A check valve, disposed inside the pump body and adjacent to the communication port, the check valve closing the communication port when the micro vacuum pump is not working; when the micro vacuum pump is working, the check valve opens the communication port.

2. The micro vacuum pump according to claim 1, wherein The check valve is an umbrella valve, the check valve including an umbrella handle portion fixedly installed on the cover and a deformable umbrella face portion, and when the micro vacuum pump is not working, the umbrella face portion maintains a state of closing the communication port.

3. The micro vacuum pump according to claim 1, characterized in that, The check valve includes a valve body adapted to the communication port and a spring fixedly arranged inside the pump body, the spring abutting against the valve body and applying a force towards the communication port to the valve body.

4. The micro vacuum pump according to claim 1, characterized in that, The check valve is composed of a multi-petal elastic structure fixedly installed on the cover and capable of closing, and when the micro vacuum pump is not working, the multi-petal elastic structure is closed and maintains a state of closing the communication port.

5. The micro vacuum pump according to claim 1, wherein An inner end portion of the cover is formed with a convex post, the communication port is opened on a side wall of the convex post, the check valve is an annular diaphragm body, the diaphragm body is installed outside the convex post and includes a top fixedly arranged on the cover and a bottom inclined towards the convex post relative to the top; when the micro vacuum pump is not working, the bottom contacts an outer wall of the convex post and maintains a state of closing the communication port.

6. The micro vacuum pump according to claim 1, characterized in that The micro vacuum pump is a diaphragm type vacuum pump, the micro vacuum pump further including a valve seat, a diaphragm seat and a motor seat arranged in sequence along the axial direction, the check valve is clamped between the cover and the valve seat, and the pumping component is installed on the diaphragm seat.

7. The micro vacuum pump according to claim 6, characterized in that, The cover has a protrusion located inside the communication port, the check valve includes a mounting portion for being clamped by the cover and the valve seat, a deformable portion located inside the mounting portion, and a ventilation hole opened on the deformable portion and adapted to the protrusion, the ventilation hole being located on the inflow path; when the micro vacuum pump is not working, the ventilation hole contacts the protrusion and the check valve maintains a state of closing the communication port.

8. The micro vacuum pump according to claim 7, characterized in that, The valve seat is provided with a convex ring and a through hole located inside the convex ring, the through hole being located on the inflow path, and the check valve is installed on the convex ring and forms a buffer chamber with the convex ring.

9. The micro vacuum pump according to claim 7, wherein An inner surface of the cover has a convex lip facing the valve seat, the convex lip being located outside the convex ring and pressing against the check valve.

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