Simulation test device for clearance flow of vacuum dry pump

Abstract

The invention relates to the technical field of clearance flow of vacuum dry pumps, in particular to a simulation test device for clearance flow of a vacuum dry pump, which comprises a test main body, a test rotor and a driving assembly. The testing main body comprises a lower shell and an end cover, and the end cover can be buckled on the accommodating chamber and is detachably connected with the accommodating chamber through a connecting piece. The bottom of the end cover is provided with an extension part, and a gap is formed between the extension part and the test rotor. The driving assembly is located outside the test main body and can be connected with the test rotor. The gas leakage rule can be obtained by simulating the gas leakage amount of the gap of the vacuum dry pump through the device, and the design of the vacuum dry pump is guided, so that the pumping performance and the reliability of the vacuum dry pump are improved.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum dry pump gap flow measurement, and in particular to a simulation test device for vacuum dry pump gap flow. Background Art

[0002] A vacuum dry pump refers to a non-contact vacuum pump that does not use oil or liquid for sealing. The current vacuum pump will not cause water and oil to flow back and diffuse, and has the advantages of high vacuum, long service life, low energy consumption, and no oil pollution. The vacuum dry pump has a rotor assembly that can rotate relative to the chamber of the vacuum dry pump, and the rotor assembly includes two rotors that rotate in opposite directions. During the operation of the vacuum dry pump, the two rotors of the vacuum dry pump rotate in opposite directions to achieve the pumping effect, and there is a gap between the rotors and between the rotors and the pump chamber. Once the gaps at the above two places are too large, the gas will flow back from the gap to the pumped chamber. In other words, a larger gap will increase the gas reflux, thereby reducing the pumping efficiency of the vacuum dry pump. At the same time, during the operation of the vacuum dry pump, the temperature rise of the rotor and the pump chamber is high, resulting in the possibility of thermal expansion between the rotor and the inner wall of the pump chamber and between the two rotors. Then a smaller gap is likely to cause the rotor to be stuck with the inner wall of the pump chamber or between the two rotors during the vacuum pumping process. That is, the design of the gap inside the vacuum dry pump is an important part of determining the pumping performance of the vacuum dry pump. Therefore, before the vacuum dry pump is put into operation, the leakage of the vacuum dry pump needs to be measured to improve the pumping performance of the vacuum dry pump.

[0003] However, in the current existing technology, only the overall leakage amount of the vacuum dry pump can be obtained, that is, the leakage amount test of the actual vacuum dry pump, which leads to the lack of precise guidance design for each gap of the vacuum dry pump, thereby greatly reducing the vacuum dry pumping performance and reliability. Summary of the invention

[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a simulation test device for the gap flow of a vacuum dry pump, which solves the problem that only the overall leakage amount of the vacuum dry pump can be obtained, that is, the leakage amount test of the actual vacuum dry pump, which leads to no precise guidance design for each gap of the vacuum dry pump, thereby greatly reducing the technical problem of the vacuum dry pumping performance.

[0005] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0006] An embodiment of the present invention provides a simulation test device for gap flow of a vacuum dry pump, comprising a test body, a test rotor located in the test body, and a drive assembly capable of driving the test rotor to rotate relative to the test body;

[0007] The test body comprises a lower shell and an end cover located above the lower shell, wherein the lower shell has a receiving chamber with an open top for receiving the test rotor, and the end cover can be buckled on the receiving chamber and detachably connected through a connecting piece to form a sealed chamber;

[0008] The bottom of the end cover has an extension portion that can extend toward the test rotor, and a gap is formed between the extension portion and the test rotor;

[0009] The driving assembly is located outside the test body, and the driving assembly can be connected to the test rotor.

[0010] Optionally, the lower shell includes a main shell, a first side end cover and a second side end cover;

[0011] The main shell has a bottom surface, a first side surface, a second side surface, a third side surface and a fourth side surface, and the first side surface corresponds to the third side surface, and the second side surface corresponds to the fourth side surface;

[0012] A through hole communicating with the outside and penetrating therethrough is provided on the first side surface and the third side surface, the axial direction of the through hole coincides with the axial direction of the test rotor, and the top of the through hole is set as the opening;

[0013] The first side end cover and the second side end cover are respectively located on the first side surface and the third side surface, and are detachably connected to the main shell through locking members to block both ends of the through hole. The rotating shafts at both ends of the test rotor are respectively mounted on the first side end cover and the second side end cover through bearings.

[0014] Optionally, air holes are respectively provided on the second side surface and the fourth side surface, one of the air holes can be connected to the chamber to be evacuated, and the other of the air holes is connected to the outside;

[0015] The air holes can ventilate toward the gap.

[0016] Optionally, the air hole is located below the gap in a horizontal plane;

[0017] The main shell is provided with an air flow channel for connecting the air hole and the gap.

[0018] Optionally, the through hole divides the main shell into a first part and a second part at the front and rear sides;

[0019] The air flow channel comprises a first inclined channel and a second inclined channel which are arranged obliquely and communicate with the air hole;

[0020] The first inclined channel is disposed in the first portion, and the second inclined channel is disposed in the second portion;

[0021] The airflow channel further includes a first rectangular groove extending downward and outward along the top inner wall of the first portion and a second rectangular groove extending downward and outward along the top inner wall of the second portion, the first rectangular groove being connected to the first inclined channel, and the second rectangular groove being connected to the second inclined channel;

[0022] The airflow communicating with the gap is formed between the air hole, the first inclined channel or the second inclined channel, and the first rectangular groove or the second rectangular groove.

[0023] Optionally, the distance between the two ends of the extension portion of the end cover and the first side wall of the first rectangular groove or the second rectangular groove is greater than the lateral length of the second side wall of the first rectangular groove or the second rectangular groove.

[0024] Optionally, the cross-sectional shape of the extension portion is any one of an arc shape, a rectangle shape or a pointed cone shape protruding downward.

[0025] Optionally, a first annular sealing groove is formed on the bottom end surface of the end cover, and a first type rubber ring is arranged in the first annular sealing groove.

[0026] Optionally, the first side end cover and the second side end cover are both provided with a second annular sealing groove near the first side surface and the third side surface, and a second type rubber ring is arranged in the second annular sealing groove.

[0027] Optionally, the drive assembly includes a motor and a magnetic coupler;

[0028] The output end of the motor is connected to the rotating shaft of the test rotor through the magnetic coupler.

[0029] The beneficial effects of the present invention are as follows: a simulation test device for the gap flow of a vacuum dry pump of the present invention can simulate the amount of gas leakage in the gap of the vacuum dry pump through the device, and the leakage law of the gas can be obtained to guide the design of the vacuum dry pump, so as to improve the pumping performance and reliability of the vacuum dry pump. Furthermore, by setting the top end cover of the test body to be detachable from the lower shell, it is possible to simulate different structural shapes between the rotor and the pump chamber according to needs, thereby changing the gap shape between the rotor and the cavity, which is convenient for measuring the rarefied gas flow rate under different types of gaps. Before use, the simulation device is used to simulate the gap between the rotor and the pump chamber of the vacuum dry pump to better determine the gap between the rotor and the pump chamber and the gap between the two rotors. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1It is a three-dimensional structural schematic diagram of the simulation test device for the gap flow of a vacuum dry pump of the present invention (the driving component is not shown);

[0031] Figure 2 for Figure 1 Schematic diagram of the longitudinal section structure in;

[0032] Figure 3 for Figure 1 A schematic diagram of a transverse cross-sectional structure in FIG. 1 (side end caps not shown);

[0033] Figure 4 It is a schematic diagram of the three-dimensional structure of the lower shell of the simulation test device for the gap flow of a vacuum dry pump of the present invention;

[0034] Figure 5 Schematic diagram of the structure of various shapes of gaps.

[0035] Description of Reference Numerals

[0036] 1: test body; 11: lower shell; 111: main shell; 111A: first part; 111B: second part; 1111: first side; 1112: second side; 1113: through hole; 112: first side end cover; 1121: second O-type rubber ring; 113: second side end cover; 12: end cover; 121: extension; 122: first O-type rubber ring; 13: connector;

[0037] 2: Test the rotor;

[0038] 3: driving assembly; 31: motor; 32: magnetic coupling;

[0039] 4: Locking piece;

[0040] 5: Bearing;

[0041] 6: Stomata;

[0042] 7: Gap;

[0043] 8: first inclined channel;

[0044] 9: Second inclined channel;

[0045] 10: first rectangular groove;

[0046] 101: Second rectangular groove. DETAILED DESCRIPTION

[0047] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below in conjunction with the accompanying drawings through specific implementation methods. Figure 4 The surface where the second side surface 1112 is located is defined as “front”; and the direction where the first side end cover 112 is located relative to the main shell 111 is defined as “left”.

[0048] See attached Figure 1-5 As shown, a simulation test device for the gap flow of a vacuum dry pump proposed in an embodiment of the present invention includes a test body 1, a test rotor 2 located in the test body 1, and a drive assembly 3 capable of driving the test rotor 2 to rotate relative to the test body 1. The test body 1 includes a lower shell 11 and an end cover 12 located above the lower shell 11, the lower shell 11 has a receiving chamber with an open top for receiving the test rotor 2, and the end cover 12 can be snapped on the receiving chamber and detachably connected through a connector 13 to form a sealed chamber. The bottom of the end cover 12 has an extension portion 121 that can extend toward the test rotor 2, and a gap 7 is formed between the extension portion 121 and the test rotor 2. The drive assembly 3 is located outside the test body 1, and the drive assembly 3 can be connected to the test rotor 2.

[0049] In the present embodiment, an adjustable rarefied gas gap flow measurement device is designed to simulate the flow of rarefied gas between the layers of a vacuum dry pump. Specifically, a simulation test device for the gap flow of a vacuum dry pump is provided. By simulating the amount of gas leakage in the gap of a vacuum dry pump through the device, the leakage law of the gas can be obtained, and the design of the vacuum dry pump can be guided to improve the pumping performance and reliability of the vacuum dry pump. The simulation device can be used to simulate the gap between the rotor and the pump chamber of the vacuum dry pump before use to better determine the gap between the rotor and the pump chamber and the gap between the two rotors. Furthermore, the top end cover 12 of the test body 1 is arranged to be detachable from the lower shell 11, so that different structural shapes between the rotor and the pump chamber can be simulated as needed, thereby changing the shape of the gap between the rotor and the cavity, specifically: the gap between the rotors can be simulated (see Figure 5 gap 2 or gap 4) and the gap between the rotor and the pump chamber (see Figure 5 The gap 1 or gap 3 in the figure is convenient for measuring the rarefied gas flow rate under different types of gaps. That is, the shape and size of the gap can be flexibly changed to simulate the flow of rarefied gas between the layers of the vacuum dry pump. It solves the technical problem that only the overall leakage amount can be obtained for the leakage amount of the vacuum dry pump, that is, the leakage amount test of the actual vacuum dry pump, which leads to no accurate guidance design for each gap of the vacuum dry pump, thereby greatly reducing the vacuum dry pumping performance.

[0050] Further, the lower shell 11 includes a main shell 111, a first side end cover 112 and a second side end cover 113. The main shell 111 has a bottom surface, a first side surface 1111, a second side surface 1112, a third side surface and a fourth side surface, and the first side surface 1111 corresponds to the third side surface, and the second side surface 1112 corresponds to the fourth side surface. A through hole 1113 that is connected to the outside and passes through is opened on the first side surface 1111 and the third side surface, and the axial direction of the through hole 1113 coincides with the axial direction of the test rotor 2, and the top of the through hole 1113 is set to be open. The first side end cover 112 and the second side end cover 113 are respectively located on the first side surface 1111 and the third side surface, and are detachably connected to the main shell 111 through a locking member 4 to block the two ends of the through hole 1113. The rotating shafts at both ends of the test rotor 2 are respectively mounted on the first side end cover 112 and the second side end cover 113 through bearings 5.

[0051] In this embodiment, the first side end cover 112 and the second side end cover 113 are arranged to be detachable relative to the main shell 111 in order to facilitate the smooth installation of the rotor in the through hole 1113, facilitate assembly and disassembly, and be simple and convenient to operate.

[0052] It should also be noted that mounting holes for placing the bearing 5 are provided on the first side end cover 112 and the second side end cover 113. The locking member 4 includes a first locking screw 41 capable of locking the first side end cover 112 and the second side end cover 113 to the first side surface 1111 and the third side surface of the main housing 111 respectively; it also includes a blocking plate 42 buckled at both ends of the outer side of the mounting hole and a plurality of second locking screws 43 capable of locking the blocking plate 42 to the first side end cover 112 and the second side end cover 113. It should also be noted that a rectangular groove is also provided between the blocking plate 42 and the first side end cover 112 or the second side end cover 113, and a third O-ring 44 is provided in the rectangular groove.

[0053] Furthermore, air holes 6 are respectively provided on the second side surface 1112 and the fourth side surface, one air hole 6 can be connected to the chamber to be vacuumed, and the other air hole 6 is connected to the outside. The air holes 6 can be ventilated toward the gap 7. Specifically, the air hole 6 in the front is the air outlet; the air hole 6 in the back is the air inlet. The air inlet is connected to the chamber to be vacuumed, and the air outlet is connected to the outside atmosphere. The gas enters from the air inlet and is discharged from the air outlet. In the overall test, an externally designed and matched vacuum system is used to measure the leakage amount.

[0054] Further, the air hole 6 is located below the gap 7 on the horizontal plane. An airflow channel for connecting the air hole 6 and the gap 7 is provided on the main shell 111. Further, the through hole 1113 divides the main shell 111 into a first part 111A and a second part 111B on the front and rear sides. The airflow channel includes a first inclined channel 8 and a second inclined channel 9 which are arranged obliquely and communicate with the air hole 6. The first inclined channel 8 is arranged in the first part 111A, and the second inclined channel 9 is arranged in the second part 111B. The airflow channel also includes a first rectangular groove 10 extending downward and outward along the top inner wall of the first part 111A and a second rectangular groove 101 extending downward and outward along the top inner wall of the second part 111B, the first rectangular groove 10 is communicated with the first inclined channel 8, and the second rectangular groove 101 is communicated with the second inclined channel 9. An airflow channel connected with the gap 7 is formed between the air hole 6, the first inclined channel 8 or the second inclined channel 9, and the first rectangular groove 10 or the second rectangular groove 101. It should be noted that the air hole 6 is arranged below the gap 7 and is matched with the air hole 6, the first inclined channel 8 or the second inclined channel 9 and the first rectangular groove 10 or the second rectangular groove 101, so that the gas flows into or out of the first rectangular groove 10 and the second rectangular groove 101 at the upper part through the flow channel, so that the gas flowing into and out of the measuring gap is uniform and stable, avoiding the influence of uncertainty caused by the direct passage of the gas.

[0055] Furthermore, the distance between the two ends of the extension portion 121 of the end cover 12 and the first side wall of the first rectangular groove 10 or the second rectangular groove 101 is greater than the lateral length of the second side wall of the first rectangular groove 10 or the second rectangular groove 101. A more spacious gas transition space can be provided, further improving the uniformity and stability of the gas.

[0056] Furthermore, the cross-sectional shape of the extension portion 121 is any one of a circular arc shape, a rectangular shape or a pointed cone shape protruding downward. Figure 5 As shown, the shape of the measuring gap can be changed by replacing different upper end covers 12 .

[0057] Furthermore, a first annular sealing groove is formed on the bottom end surface of the end cover 12, and a first O-type rubber ring 122 is disposed in the first annular sealing groove, thereby improving the sealing effect between the end cover 12 and the main shell 111.

[0058] Furthermore, the first side end cover 112 and the second side end cover 113 are both provided with a second annular sealing groove near the first side surface 1111 and the third side surface, and a second O-type rubber ring 1121 is arranged in the second annular sealing groove, thereby improving the sealing effect between the first side end cover 112 and the second side end cover 113.

[0059] Furthermore, the driving assembly 3 includes a motor 31 and a magnetic coupler 32. The output end of the motor 31 is connected to the test rotor 2 by extending the rotor shaft of the output end of the magnetic coupler 32 into the sealed chamber. The magnetic coupler 32 used between the motor 31 and the rotating shaft reduces the volume of the cavity, thereby reducing the leakage of the gas in the gap and improving the accuracy of the flow measurement in the gap.

[0060] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0061] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0063] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0064] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A simulation test device for the gap flow of a vacuum dry pump, characterized in that: It comprises a test body (1), a test rotor (2) located in the test body (1), and a driving assembly (3) capable of driving the test rotor (2) to rotate relative to the test body (1); The test body (1) comprises a lower shell (11) and an end cover (12) located above the lower shell (11), wherein the lower shell (11) has a receiving chamber with an open top for receiving the test rotor (2), and the end cover (12) can be fastened to the receiving chamber and detachably connected via a connecting piece (13) to form a sealed chamber; The bottom of the end cover (12) has an extension portion (121) capable of extending toward the test rotor (2), and a gap (7) is formed between the extension portion (121) and the test rotor (2); The driving component (3) is located outside the test body (1), and the driving component (3) can be connected to the test rotor (2).

2. The simulation test device for the gap flow of a vacuum dry pump according to claim 1, characterized in that: The lower housing (11) comprises a main housing (111), a first side end cover (112) and a second side end cover (113); The main shell (111) has a bottom surface, a first side surface (1111), a second side surface (1112), a third side surface and a fourth side surface, and the first side surface (1111) corresponds to the third side surface, and the second side surface (1112) corresponds to the fourth side surface; A through hole (1113) communicating with the outside and penetrating therethrough is provided on the first side surface (1111) and the third side surface, the axial direction of the through hole (1113) coincides with the axial direction of the test rotor (2), and the top of the through hole (1113) is arranged as the opening; The first side end cover (112) and the second side end cover (113) are respectively located on the first side surface (1111) and the third side surface, and are detachably connected to the main housing (111) via a locking member (4) to block the two ends of the through hole (1113); the rotating shafts at both ends of the test rotor (2) are respectively mounted on the first side end cover (112) and the second side end cover (113) via bearings (5).

3. The simulation test device for the gap flow of a vacuum dry pump according to claim 2, characterized in that: Air holes (6) are respectively provided on the second side surface (1112) and the fourth side surface, one of the air holes (6) can be connected to the chamber to be evacuated, and the other of the air holes (6) is connected to the outside; The air hole (6) is capable of ventilating toward the gap (7).

4. The simulation test device for the gap flow of a vacuum dry pump according to claim 3, characterized in that: The air hole (6) is located below the gap (7) in the horizontal plane; The main shell (111) is provided with an air flow channel for connecting the air hole (6) and the gap (7).

5. The simulation test device for the gap flow of a vacuum dry pump according to claim 4, characterized in that: The through hole (1113) divides the main shell (111) into a first part (111A) and a second part (111B) at the front and rear sides; The air flow channel comprises a first inclined channel (8) and a second inclined channel (9) which are arranged in an inclined manner and communicate with the air hole (6); The first inclined channel (8) is arranged in the first part (111A), and the second inclined channel (9) is arranged in the second part (111B); The airflow channel further comprises a first rectangular groove (10) extending downward and outward along the top inner wall of the first part (111A) and a second rectangular groove (101) extending downward and outward along the top inner wall of the second part (111B), the first rectangular groove (10) being connected to the first inclined channel (8), and the second rectangular groove (101) being connected to the second inclined channel (9); The air flow channel connected to the gap (7) is formed between the air hole (6), the first inclined channel (8) or the second inclined channel (9) and the first rectangular groove (10) or the second rectangular groove (101).

6. The simulation test device for the gap flow of a vacuum dry pump according to claim 5, characterized in that: The distance between the two ends of the extension portion (121) of the end cover (12) and the first side wall of the first rectangular groove (10) or the second rectangular groove (101) is greater than the lateral length of the second side wall of the first rectangular groove (10) or the second rectangular groove (101).

7. The simulation test device for gap flow of a vacuum dry pump according to claim 1, characterized in that: The cross-sectional shape of the extension portion (121) is any one of an arc shape, a rectangle shape or a pointed cone shape protruding downward.

8. The simulation test device for gap flow of a vacuum dry pump according to claim 1, characterized in that: A first annular sealing groove is provided on the bottom end surface of the end cover (12), and a first O-type rubber ring (122) is arranged in the first annular sealing groove.

9. The simulation test device for gap flow of a vacuum dry pump according to claim 1, characterized in that: The first side end cover (112) and the second side end cover (113) are both provided with a second annular sealing groove near the first side surface (1111) and the third side surface, and a second O-type rubber ring (1121) is arranged in the second annular sealing groove.

10. The simulation test device for gap flow of a vacuum dry pump according to claim 1, characterized in that: The driving assembly (3) comprises a motor (31) and a magnetic coupling (32); The output end of the motor (31) is connected to the rotating shaft of the test rotor (2) via the magnetic coupler (32).

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