Miniature vacuum pump and miniature vacuumizing device

Abstract

The embodiment of the utility model provides a miniature vacuum pump and a miniature vacuumizing device, the miniature vacuum pump comprises an air collecting and exhausting chamber, a driving motor and a vacuum breaking mechanism assembled in the air collecting and exhausting chamber, and the vacuum breaking mechanism comprises an air inlet hole penetrating through the bottom wall of the air collecting and exhausting chamber; the pressing plate is movably sleeved on the section of the output shaft in the collecting and exhausting chamber and is used for movably covering the air inlet hole, a through hole is formed in the middle of the pressing plate, and the output shaft penetrates through the through hole; the centrifugal assembly comprises a centrifugal swing rod, the centrifugal swing rod presses and positions the pressing plate to the sealing position corresponding to the sealing and covering air inlet hole when rotating along with the output shaft, and one end of the centrifugal swing rod is provided with a ball which is used for abutting against the pressing plate and rolling on the plate face of the pressing plate; the area, used for making contact with the balls, of the pressing plate is correspondingly sunken to form pits, the pit walls of the pits are concave spherical surfaces or circular truncated cone side faces with large pit openings and small pit bottoms, and the balls abut against the pit walls of the pits correspondingly. The embodiment of the utility model can simplify the assembly and reduce the cost.

Description

Technical Field

[0001] This utility model relates to the field of vacuum pumping device technology, and in particular to a micro vacuum pump and a micro vacuum pumping device. Background Technology

[0002] Existing small household appliances such as mini vacuum packaging machines and electric breast pumps all require vacuuming devices. Due to varying requirements in performance indicators such as power, vacuum level, lifespan, noise, size, and safety, large vacuum pumps and vacuuming devices widely used in industry and commerce are not suitable; instead, miniature vacuuming devices are required. A typical miniature vacuuming device consists of a miniature vacuum pump and a controller. The miniature vacuum pump includes an exhaust chamber with an inlet and an outlet, a cup assembly assembled within the exhaust chamber, a drive motor with an output shaft passing through the bottom wall of the exhaust chamber and extending into the inner cavity, driving the cup assembly, and a vacuum breaking component assembled within the exhaust chamber. The vacuum breaking component can perform vacuuming and vacuum venting in both the driven motor's on and off states.

[0003] A vacuum breaking component of a current miniature vacuum pump includes: an air inlet formed through the bottom wall of the exhaust chamber; a pressure plate movably sleeved on the section of the output shaft located in the exhaust chamber and correspondingly covering the air inlet; a rotating seat coaxially fixedly assembled on the output shaft and located on the side of the pressure plate away from the bottom wall; a centrifugal pendulum pivotally mounted on the outer surface of the rotating seat in the middle section; a pivot bracket protruding from the outer side of the rotating seat; the center of gravity of the centrifugal pendulum is set at the end away from the rotating seat; the end of the centrifugal pendulum near the rotating seat bends and extends towards the pressure plate to form a pressing part for pressing against the pressure plate; in addition, to ensure smooth rotation between the pressure plate and the centrifugal pendulum and reduce friction, a through hole is usually opened in the middle of the pressure plate, through which the output shaft passes; a positioning groove is provided on the side of the pressing part facing the pressure plate; a ball is assembled in the positioning groove; a part of the ball protrudes from the opening of the positioning groove and presses against the pressure plate.

[0004] However, the inventors discovered in specific embodiments that, since the side of the pressure plate on which the ball bearings press is flat, when the ball bearings push against the pressure plate, the force exerted on the pressure plate is perpendicular to the surface of the pressure plate. This makes the rolling of the ball bearings on the pressure plate usually not smooth enough, resulting in a slow downward movement of the pressure plate and an inability to quickly seal the air inlet. In addition, although the ball bearings are assembled in the positioning groove of the pressing part, during the testing and actual use of the micro vacuum pump, external vibrations can easily cause the ball bearings to fall out of the positioning groove, affecting the normal use of the micro vacuum pump. Utility Model Content

[0005] The technical problem to be solved by this utility model embodiment is to provide a miniature vacuum pump that can more effectively push the pressure plate to the sealing position and prevent the balls from falling off.

[0006] The further technical problem to be solved by this utility model embodiment is to provide a miniature vacuum device that can more effectively push the pressure plate to the sealing position and prevent the balls from falling off.

[0007] To solve the above-mentioned technical problems, this utility model embodiment first provides the following technical solution: a miniature vacuum pump, including an exhaust chamber, a drive motor extending into the exhaust chamber through the bottom wall of the exhaust chamber with its output shaft passing through it, and a vacuum breaking mechanism assembled in the exhaust chamber, the vacuum breaking mechanism including:

[0008] An air inlet hole that penetrates the bottom wall of the exhaust chamber;

[0009] A pressure plate, movably fitted onto the section of the output shaft located within the exhaust chamber and used to movably cover the air inlet, has a through hole in its center through which the output shaft passes; and

[0010] A centrifugal assembly assembled at the end of the output shaft and rotating synchronously with the output shaft, the centrifugal assembly including a centrifugal pendulum rod that presses and positions the pressure plate at a sealing position corresponding to the sealing of the air inlet when rotating with the output shaft, one end of the centrifugal pendulum rod being provided with a ball bearing for abutting against the pressure plate and rolling on the surface of the pressure plate;

[0011] The pressure plate is used to form a corresponding recess in the area that contacts the ball, the wall of the recess being a concave spherical surface or the side of a frustum with a large opening and a small bottom, and the ball abuts against the wall of the recess.

[0012] Furthermore, the perforation is located at the center of the recess.

[0013] Furthermore, the centrifugal pendulum has a positioning groove at one end facing the pressure plate, and the ball bearing is assembled in the positioning groove and protrudes from the opening of the positioning groove to abut against the wall of the recess.

[0014] Furthermore, a limiting plate is assembled on the outside of the positioning groove to confine the ball within the positioning groove. The limiting plate has a window for a portion of the ball to protrude out. The window is a circle with a diameter smaller than the diameter of the ball, or a regular polygon with an inscribed circle diameter smaller than the diameter of the ball. Alternatively, the width of the groove is slightly smaller than the diameter of the ball, and the ball is squeezed into the positioning groove from the groove.

[0015] Furthermore, a receiving groove is provided on the side of the pressure plate facing the bottom wall, directly opposite the air inlet. Several stop protrusions are symmetrically provided at the opening of the receiving groove. A sealing gasket is assembled in the receiving groove, which is blocked and limited by the stop protrusions and protrudes from the opening of the receiving groove. The pressure plate is also provided with a guide hole axially parallel to the output shaft. A guide rod is provided on the bottom wall, which is parallel to the output shaft and passes through the guide hole.

[0016] Furthermore, the centrifugal assembly also includes a rotating seat coaxially fixedly assembled on the output shaft and located on the side of the pressure plate away from the bottom wall. A pivot frame is provided on the outer side of the rotating seat. The middle section of the centrifugal pendulum is pivotally mounted on the pivot frame by means of a pivot. The pivot is orthogonal or oblique to the output shaft. The center of gravity of the centrifugal pendulum is set at the end away from the output shaft. The end of the centrifugal pendulum close to the output shaft forms a pressing part. The ball bearings are assembled on the pressing part.

[0017] Furthermore, the vacuum breaking mechanism also includes a reset elastic element for pushing the pressure plate to a through position that connects the air inlet to the inner cavity of the exhaust chamber when the drive motor stops. The pressure plate and the bottom surface of the rotating seat have a gap in the axial direction of the output shaft. The end of the pressing part is inserted into the gap and abuts against the bottom surface of the rotating seat under the action of the pressure plate when the drive motor stops. The pressure plate and the bottom surface of the rotating seat have a gap in the axial direction of the output shaft. The end of the pressing part is inserted into the gap. When the output shaft is not rotating, the pressing part abuts against the bottom surface of the rotating seat or the side surface of the output shaft under the action of the reset elastic element.

[0018] Furthermore, the centrifugal pendulum includes a connecting portion located in the middle and having a pivot hole at one end for the pivot to pass through; a counterweight end formed by bending the end of the connecting portion with the pivot hole and extending it toward the side away from the output shaft; and a pressing portion formed by bending the end of the connecting portion away from the pivot hole. The counterweight end is provided with a receiving groove, in which a counterweight block made of a high-density material is embedded. The bottom wall of the receiving groove is also provided with an operating port that communicates with the inner cavity of the receiving groove for inserting a corresponding tool to push the counterweight block out of the groove opening.

[0019] Furthermore, a plurality of pivot frames are symmetrically arranged on the outer side of the rotating seat around the central axis of the rotating seat, and a centrifugal pendulum is pivotally mounted on each pivot frame. The pressing parts of each centrifugal pendulum are symmetrically distributed around the output shaft.

[0020] On the other hand, in order to solve the above-mentioned further technical problems, the present invention provides the following technical solution: a miniature vacuum pump, including a miniature vacuum pump and a controller connected to the drive motor of the miniature vacuum pump for controlling the working state of the drive motor, wherein the miniature vacuum pump is a vacuum pump as described above.

[0021] After adopting the above technical solution, the present invention embodiment has at least the following beneficial effects: The pressure plate of the vacuum breaking mechanism in the present invention is used to form a corresponding recess in the area where it contacts the ball bearing, and the wall of the recess is designed as a concave spherical surface or a frustum side with a large opening and a small bottom. When the centrifugal pendulum is driven by the output shaft of the drive motor to press against the pressure plate, the ball bearing can smoothly roll and rise spirally towards the opening on the wall of the recess, thereby effectively pressing down the pressure plate and making the pressure plate quickly reach the sealing position covering the air inlet. In addition, the recess can also effectively limit the ball bearing and prevent the ball bearing from falling off the centrifugal pendulum. Attached Figure Description

[0022] Figure 1 This is a schematic diagram showing the split structure of an optional embodiment of the miniature vacuum pump of this utility model.

[0023] Figure 2 This is a schematic diagram of the assembly structure of an optional embodiment of the miniature vacuum pump of this utility model.

[0024] Figure 3 This is a schematic diagram showing the disassembled structure of the vacuum breaking mechanism in an optional embodiment of the miniature vacuum pump of this utility model.

[0025] Figure 4 This is a schematic diagram of the assembly structure of the vacuum breaking mechanism, excluding the reset elastic element, in an optional embodiment of the micro vacuum pump of this utility model.

[0026] Figure 5 This is a cross-sectional structural diagram of an optional embodiment of the miniature vacuum pump of this utility model, showing the ball bearing and the pressure part in a disassembled state.

[0027] Figure 6 This is a cross-sectional structural diagram of an optional embodiment of the miniature vacuum pump of this utility model, showing the assembled state of the ball bearing and the pressure part.

[0028] Figure 7 This is a schematic diagram of the disassembled structure of a centrifugal pendulum after inverting it, which is an optional embodiment of the micro vacuum pump of this utility model.

[0029] Figure 8 This is a schematic diagram showing the disassembled structure of the pressure plate in an optional embodiment of the micro vacuum pump of this utility model.

[0030] Figure 9This is a schematic cross-sectional view of the pressure plate when the air inlet is opened in an optional embodiment of the micro vacuum pump of this utility model.

[0031] Figure 10 This is a cross-sectional structural diagram of an optional embodiment of the micro vacuum pump of this utility model, with the pressure plate covering the air inlet.

[0032] Figure 11 This is a schematic diagram of a possible embodiment of the miniature vacuum pumping device of this utility model. Detailed Implementation

[0033] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following illustrative embodiments and descriptions are only used to explain the present utility model and are not intended to limit the present utility model. Moreover, the embodiments and features in the embodiments of the present application can be combined with each other unless otherwise specified.

[0034] like Figures 1-10 As shown, an optional embodiment of this utility model provides a miniature vacuum pump A, including a vacuum chamber 1, a drive motor 3 extending into the vacuum chamber 1 through the bottom wall of the vacuum chamber 1 with an output shaft 30, and a vacuum breaking mechanism 5 assembled in the vacuum chamber 1. The vacuum breaking mechanism 5 includes:

[0035] An air inlet 50 is formed by penetrating the bottom wall 1a of the exhaust chamber 1;

[0036] A pressure plate 52, movably fitted onto the section of the output shaft 30 located within the exhaust chamber 1 and used to movably cover the air inlet 50, has a through hole 521 in its center through which the output shaft 30 passes; and

[0037] A centrifugal assembly 53 is assembled at the end of the output shaft 30 and rotates synchronously with the output shaft 30. The centrifugal assembly 53 includes a centrifugal swing rod 54 that presses and positions the pressure plate 52 at a sealing position corresponding to the sealing of the air inlet 50 when rotating with the output shaft 30. One end of the centrifugal swing rod 54 is provided with a ball bearing 55 for abutting against the pressure plate 52 and rolling on the surface of the pressure plate 52.

[0038] The pressure plate 52 is used to form a corresponding recess 522 in the area that contacts the ball 55. The wall of the recess 522 is a concave spherical surface or the side of a frustum with a large opening and a small bottom. The ball 55 abuts against the wall of the recess 522.

[0039] In this embodiment of the invention, the pressure plate 52 of the vacuum breaking mechanism 5 is recessed in the area that contacts the ball bearing 55 to form a recess 522. The wall of the recess 522 is designed as a concave spherical surface or a frustum side with a large opening and a small bottom. When the centrifugal pendulum 54 presses against the pressure plate 52 under the drive of the output shaft 30 of the drive motor 3, the ball bearing 55 can smoothly roll and rise spirally towards the opening on the wall of the recess 522, thereby effectively pressing down the pressure plate 52 and making the pressure plate 52 quickly reach the sealing position covering the air inlet 50. In addition, the recess 522 can also effectively limit the ball bearing 55 and prevent the ball bearing 55 from falling off the centrifugal pendulum 54.

[0040] In practice, the air intake chamber 1 is typically equipped with an air intake nozzle 10 and an exhaust port 12 to achieve air intake and exhaust.

[0041] In one optional embodiment of this utility model, such as Figures 1-4 As shown, the perforation 521 is located at the center of the recess 522. In this embodiment, the perforation 521 is designed in the above manner, so that the recess 522 surrounds the output shaft 30 passing through the perforation 521 with the perforation 521 as the center, which facilitates the smooth spiral rolling and lifting of the ball bearing 55 along the centrifugal swing arm 54 on the recess wall. In a specific implementation, the recess 522 can be an annular recess surrounding the perforation 521.

[0042] In one optional embodiment of this utility model, such as Figures 5-8 As shown, the centrifugal pendulum 54 has a positioning groove 541 at one end facing the pressure plate 52. The ball bearing 55 is assembled in the positioning groove 541 and protrudes from the opening of the positioning groove 541, abutting against the wall of the recess 522. In this embodiment, by providing a positioning groove 541 on the centrifugal pendulum 54, after the ball bearing 55 is assembled in the positioning groove 541, a portion of the ball bearing 55 protrudes from the opening of the positioning groove 541 and presses against the wall of the recess 522, which facilitates the installation of the ball bearing 55 and allows the ball bearing 55 to remain in contact with the wall of the recess 522. Specifically, the positioning groove 541 can be a spherical groove, a cylindrical groove, or a polygonal prism groove with a regular polygonal cross-section. The inner wall of the positioning groove 541 effectively abuts against the positioning ball bearing 55, which can effectively prevent the ball bearing 55 from moving within the positioning groove 541, but does not hinder the ball bearing 55 from rotating around its own center.

[0043] In one optional embodiment of this utility model, such as Figures 5-6As shown, a limiting plate 542 is assembled on the outer side of the slot 541a of the positioning groove 541 to confine the ball 55 within the positioning groove 541. The limiting plate 542 has a window 542a for a portion of the ball 55 to protrude out. The window 542a is a circle with a diameter smaller than the diameter of the ball 55, or a regular polygon with an inscribed circle diameter smaller than the diameter of the ball 55; or, as shown... Figure 7 As shown, the width of the slot 541a is slightly smaller than the diameter of the ball 55, and the ball 55 is pressed into the positioning groove 541 from the slot 541a. In this embodiment, the ball 55 assembled in the positioning groove 541 is secured by a limiting plate 542. During assembly, the ball 55 and the limiting plate 542 are installed sequentially, which facilitates installation. In another assembly method, since the width of the slot 541a is slightly smaller than the diameter of the ball 55, during specific assembly, a larger pressure is directly used to press the ball 55 from the slot 541a into the positioning groove 541, resulting in a simpler overall structure.

[0044] In one optional embodiment of this utility model, such as Figure 3 , Figures 8-10 As shown, a receiving groove 523 is provided on the side of the pressure plate 52 facing the bottom wall 1a, directly opposite the air inlet 50. A plurality of stop protrusions 523a are symmetrically arranged at the opening of the receiving groove 523. A sealing gasket 524, blocked and limited by the stop protrusions 523a and protruding from the opening of the receiving groove 523, is assembled within the receiving groove 523. The pressure plate 52 also has a guide hole 525 axially parallel to the output shaft 30. A guide rod 14, parallel to the output shaft 30 and correspondingly passing through the guide hole 525, is provided on the bottom wall 1a. In this embodiment, the sealing gasket 524 effectively enhances the sealing effect of the pressure plate 52 on the air inlet 50, ensuring the airtightness of the micro vacuum pump during vacuuming operations. Furthermore, the sealing gasket 524 is assembled within the receiving groove 523 by being blocked and limited by the stop protrusions 523a, making assembly very convenient. In a specific implementation, the bottom surface of the pressure plate 52 is provided with a recess, and the sealing gasket 524 is embedded in the recess. Furthermore, by sliding the pressure plate 52 onto the guide rod 14 through the guide hole 525, the guide hole 525 slides up and down on the guide rod 14, effectively guiding the up-and-down movement of the pressure plate 52. In a specific implementation, the bottom end of the guide rod 14 is inserted and fixed in a pre-set positioning hole in the bottom wall 1a.

[0045] In one optional embodiment of this utility model, such as Figure 1 and Figure 3As shown, the centrifugal assembly 53 also includes a rotating seat 56 coaxially fixedly assembled on the output shaft 30 and located on the side of the pressure plate 52 away from the bottom wall. A pivot frame 561 is provided on the outer side of the rotating seat 56. The middle section of the centrifugal pendulum 54 is pivotally mounted on the pivot frame 561 by means of a pivot 54a. The pivot 54a is orthogonal or oblique to the output shaft 30. The center of gravity of the centrifugal pendulum 54 is set at the end away from the output shaft 30. The end of the centrifugal pendulum 54 close to the output shaft 30 forms a pressing part 543. The ball bearing 55 is assembled on the pressing part 543. In this embodiment, when the micro vacuum pump needs to perform vacuuming and the drive motor 3 is started, since the center of gravity of the centrifugal pendulum 54 is set at the end away from the rotating seat 56, the output shaft 30 of the drive motor 3 rotates, causing the rotating seat 56 to rotate, and the centrifugal pendulum 54 deflects around the pivot 54a under the action of centrifugal force. At this time, the end of the centrifugal pendulum 54 near the rotating seat 5 then pushes against the pressure plate 52, thereby covering the air inlet 50 with the pressure plate 52, thus isolating the inner cavity of the exhaust chamber 1 from the outside atmosphere, achieving... Normal vacuuming operation; however, when the micro vacuum pump needs to perform a vacuum purging operation and the drive motor 3 is turned off, the output shaft 30 and the rotating seat 56 of the drive motor 3 stop rotating, the centrifugal force disappears, and the pressing part 543 of the centrifugal pendulum 54 no longer applies pressure to the pressure plate 52. Due to the pressure difference between the inner cavity of the exhaust chamber 1 and the outside atmosphere, the pressure plate 52 is pushed open by the outside atmosphere, the air inlet 50 opens, and the inner cavity of the exhaust chamber 1 is connected to the outside atmosphere. The outside atmosphere enters the inner cavity of the exhaust chamber 1 through the air inlet 50, realizing the vacuum purging operation. Specifically, to ensure good swing of the centrifugal pendulum 54, the pivot 54a and the output shaft 30 are preferably orthogonal.

[0046] In one optional embodiment of this utility model, such as Figure 1 , Figures 3-4 , Figures 8-10As shown, the vacuum breaking mechanism 5 further includes a reset elastic element 58 for pushing the pressure plate 52 to a through position where the air inlet 50 communicates with the inner cavity of the exhaust chamber 1 when the drive motor 3 stops. The pressure plate 52 and the bottom surface of the rotating seat 56 have a gap 52a in the axial direction of the output shaft 30. The end of the pressing part 543 is inserted into the gap 52a. When the output shaft 30 is not rotating, the pressing part 543 abuts against the bottom surface of the rotating seat 56 or the side surface of the output shaft 30 under the pushing of the reset elastic element 58. In this embodiment, by providing the reset elastic element 58, the external atmosphere can be assisted in quickly pushing the pressure plate 52 open, thereby improving the vacuum breaking efficiency. Specifically, the reset elastic element 58 can be a helical compression spring sleeved on the output shaft 30. During assembly, one end of the reset elastic element 58 abuts against the side of the pressure plate 52 facing the bottom wall 1a of the exhaust chamber 1, while the other end abuts against the inner surface of the bottom wall 1a of the exhaust chamber 1. In addition, when the drive motor 3 is not started, the output shaft 30 will not drive the centrifugal pendulum 54 to revolve. The centrifugal pendulum 54 will rotate around the pivot 54a under its own gravity until the end away from the output shaft 30 falls down, causing the pressing part 543 to move towards the bottom surface of the rotating seat 56. Finally, the end of the pressing part 543 abuts against the bottom surface of the rotating seat 56 and is positioned. This can prevent the centrifugal pendulum 54 from rotating too much around the pivot 54a, thereby avoiding the centrifugal pendulum 54 from failing to quickly rotate around the pivot 54a to the position that seals the air inlet 50 when the drive motor 3 is started, which can effectively shorten the working response time of the micro vacuum pump.

[0047] In one optional embodiment of this utility model, such as Figure 3As shown, the centrifugal pendulum 54 includes a connecting portion 545 located in the middle and having a pivot hole 545a at one end for the pivot 54a to pass through; a counterweight end 547 extending from the end of the connecting portion 545 with the pivot hole 545a, bent and extending toward the side away from the output shaft 30; and a pressing portion 543 extending from the end of the connecting portion 545 away from the pivot hole 545a, bent and extending accordingly. The counterweight end 547 is provided with a receiving groove 5470, in which a counterweight block 5472 made of a high specific gravity material is embedded. The bottom wall of the receiving groove 5470 is also provided with an operating port 5474 that communicates with the inner cavity of the receiving groove 5470 and allows a corresponding tool to be inserted to push the counterweight block 5472 out of the groove opening of the receiving groove 5470. In this embodiment, the centrifugal pendulum 54 includes a connecting part 545, a counterweight end 547, and a pressing part 543. By adding a counterweight block 5472 to the counterweight end 547, the center of gravity position of the centrifugal pendulum 54 can be effectively adjusted, so that the center of gravity is set at the end away from the rotating seat 56. Moreover, by providing a receiving groove 5470, the assembly of the counterweight block 5472 is very simple. Furthermore, by providing an operating port 5474, it is convenient to remove the counterweight block 5472 from the receiving groove 5470. In this embodiment, the structure is relatively simple, and the center of gravity position of the entire centrifugal pendulum 54 can be easily adjusted by adjusting the weight of the counterweight end 547.

[0048] In one optional embodiment of this utility model, such as Figures 1-4 , Figures 8-10 As shown, a plurality of pivot frames 561 are symmetrically arranged on the outer side of the rotating seat 56 around the central axis of the rotating seat 56. Each pivot frame 561 is pivotally mounted with a centrifugal pendulum 54, and the pressing parts 543 of each centrifugal pendulum 54 are symmetrically distributed around the output shaft 30. In this embodiment, by symmetrically arranging centrifugal pendulums 54 on the two side walls of the rotating seat 56, when the rotating seat 56 rotates under the drive of the output shaft 30, each centrifugal pendulum 54 always applies a symmetrical pushing force to the pressure plate 52, so that the pressure plate 52 is stably maintained in the position covering the air inlet 50, ensuring the sealing of the pressure plate 52 to the air inlet 50.

[0049] On the other hand, such as Figure 10 As shown in the figure, this utility model embodiment further provides a miniature vacuum pumping device, including a miniature vacuum pump A and a controller B connected to the drive motor 3 of the vacuum pump A for controlling the working state of the drive motor 3. The miniature vacuum pump is the same as in the above embodiment. In this embodiment, the miniature vacuum pumping device uses the aforementioned miniature vacuum pump A, which can effectively reduce the size and lower production costs and operating noise.

[0050] Additionally, the exhaust chamber includes a cylinder body with several vertically connected and mutually isolated chambers, a bottom shell and a valve plate respectively sealed and connected to the bottom and top of the cylinder body, a top cover sealed and connected to the top of the valve plate, and a cup assembly assembled between the cylinder body and the bottom shell. The air inlet and air inlet hole are both located on the bottom shell. The vacuum breaking mechanism 7 is assembled inside the bottom shell. The output shaft of the drive motor extends from the bottom surface of the bottom shell into the interior of the bottom shell. The exhaust nozzle is located on the top cover, and the valve plate has airflow holes. The assembly includes a ferrule for covering the outlet end of the airflow hole, and a cup assembly comprising a swing arm with multiple piston pins and multiple cups connected together. The multiple piston pins and cups extend into the cylinder chamber from the bottom and top of each cylinder chamber respectively and are nested together in the cylinder chamber. The bottom of the swing arm is provided with an eccentric shaft, the bottom of which is fixed to the rotating seat 56. The central axis of the eccentric shaft and the output shaft 30 are obliquely intersecting. Multiple parts located outside the cylinder chamber are clamped and fixed by the valve plate and the cylinder body.

[0051] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the scope of protection of the present invention.

Claims

1. A miniature vacuum pump, comprising a vacuum chamber, a drive motor extending into the vacuum chamber through the bottom wall of the vacuum chamber via an output shaft, and a vacuum breaking mechanism assembled within the vacuum chamber, the vacuum breaking mechanism comprising: An air inlet hole that penetrates the bottom wall of the exhaust chamber; A pressure plate, movably fitted onto the section of the output shaft located within the exhaust chamber and used to movably cover the air inlet, has a through hole in its center through which the output shaft passes; and A centrifugal assembly assembled at the end of the output shaft and rotating synchronously with the output shaft, the centrifugal assembly including a centrifugal pendulum rod that presses and positions the pressure plate at a sealing position corresponding to the sealing of the air inlet when rotating with the output shaft, one end of the centrifugal pendulum rod being provided with a ball bearing for abutting against the pressure plate and rolling on the surface of the pressure plate; The characteristic feature is that the pressure plate is used to form a recess in the area that contacts the ball, the wall of the recess is a concave spherical surface or a frustum side surface with a large opening and a small bottom, and the ball abuts against the wall of the recess.

2. The miniature vacuum pump as described in claim 1, characterized in that, The perforation is located at the center of the recess.

3. The miniature vacuum pump as described in claim 1, characterized in that, One end of the centrifugal pendulum is provided with a positioning groove, and the ball bearing is assembled in the positioning groove and protrudes from the opening of the positioning groove to abut against the wall of the recess.

4. The miniature vacuum pump as described in claim 3, characterized in that, A limiting plate is assembled on the outside of the groove opening to confine the ball within the groove. The limiting plate has a window for a portion of the ball to protrude out. The window is a circle with a diameter smaller than the diameter of the ball, or a regular polygon with an inscribed circle diameter smaller than the diameter of the ball. Alternatively, the width of the groove opening is smaller than the diameter of the ball, and the ball is squeezed into the positioning groove from the groove opening.

5. The miniature vacuum pump as described in claim 1, characterized in that, A receiving groove is provided on the side of the pressure plate facing the bottom wall, directly opposite the air inlet. Several stop protrusions are symmetrically arranged at the opening of the receiving groove. A sealing gasket is assembled in the receiving groove, which is blocked and limited by the stop protrusions and protrudes from the opening of the receiving groove. The pressure plate is also provided with a guide hole axially parallel to the output shaft. A guide rod is provided on the bottom wall, which is parallel to the output shaft and passes through the guide hole.

6. The miniature vacuum pump as described in claim 1, characterized in that, The centrifugal assembly also includes a rotating seat coaxially fixedly assembled on the output shaft and located on the side of the pressure plate away from the bottom wall. A pivot frame is provided on the outer side of the rotating seat. The middle section of the centrifugal pendulum is pivotally mounted on the pivot frame by means of a pivot. The pivot is orthogonal or oblique to the output shaft. The center of gravity of the centrifugal pendulum is set at the end away from the output shaft. The end of the centrifugal pendulum close to the output shaft forms a pressing part. The ball bearings are assembled on the pressing part.

7. The miniature vacuum pump as described in claim 6, characterized in that, The vacuum breaking mechanism further includes a reset elastic element for pushing the pressure plate to a through position that connects the air inlet to the inner cavity of the exhaust chamber when the drive motor stops. The pressure plate and the bottom surface of the rotating seat have a gap in the axial direction of the output shaft. The end of the pressing part is inserted into the gap and abuts against the bottom surface of the rotating seat or the side surface of the output shaft under the action of the pressure plate when the drive motor stops.

8. The miniature vacuum pump as described in claim 6, characterized in that, The centrifugal pendulum includes a connecting part located in the middle and having a pivot hole at one end for the pivot to pass through; a counterweight end formed by bending the end of the connecting part with the pivot hole and extending it toward the side away from the output shaft; and a pressing part formed by bending the end of the connecting part away from the pivot hole. The counterweight end is provided with a receiving groove, in which a counterweight block made of a high specific gravity material is embedded. The bottom wall of the receiving groove is also provided with an operating port that communicates with the inner cavity of the receiving groove for inserting a corresponding tool to push the counterweight block out of the groove opening.

9. The miniature vacuum pump as described in claim 6, characterized in that, Multiple pivot frames are symmetrically arranged on the outer side of the rotating seat around the central axis of the rotating seat. Each pivot frame is pivotally mounted with a centrifugal pendulum. The pressing parts of each centrifugal pendulum are symmetrically distributed around the output shaft.

10. A miniature vacuum pumping device, comprising a miniature vacuum pump and a controller connected to a drive motor of the miniature vacuum pump for controlling the operating state of the drive motor, characterized in that, The micro vacuum pump is the micro vacuum pump as described in any one of claims 1-9.

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