Staggered labyrinth seal structure for vortex vacuum pump and vortex vacuum pump

Abstract

The invention provides a staggered labyrinth seal structure for a vortex vacuum pump and the vortex vacuum pump, and relates to the field of vortex vacuum pumps. The vortex vacuum pump comprises a volute and an impeller arranged in the volute, the staggered labyrinth sealing structure comprises first sealing structures arranged on the end faces of the two sides of the impeller and second sealing structures arranged on the inner end face of the volute, and the first sealing structures and the second sealing structures are opposite and arranged in a staggered mode to form a concave-convex staggered sealing path. A complex fluid path is formed through the concave-convex sealing structures which are arranged in a staggered mode, so that efficient sealing is achieved, the leakage risk is remarkably reduced, and the durability of equipment is improved.

Description

Technical Field

[0001] The present invention relates to the field of vortex vacuum pumps, and in particular to a staggered labyrinth sealing structure for a vortex vacuum pump and a vortex vacuum pump. Background Art

[0002] Vortex vacuum pump, also known as side suction pump, is a special vane pump. Compared with centrifugal pumps of the same speed, it has high head and is easy to self-prime. Compared with positive displacement pumps of the same head, it has simple and compact structure, light weight, low noise and high reliability. It is widely used in vacuum extraction, gas transportation and gas circulation in industrial production. Its performance and efficiency are crucial to the overall operation of the system.

[0003] The vortex vacuum pump mainly relies on the impeller rotating blades to push the medium in the groove out and then fold back to form a "vortex" after hitting the vortex wall of the pump housing to pressurize the medium. While the medium forms a vortex, it enters the multiple blade grooves that are symmetrically and evenly distributed along the outer edge of the impeller in turn, and is pressurized step by step until it flows out from the outlet of the vortex pump. In this process, some of the medium also flows away from the gap between the rotating impeller wall and the stationary pump housing wall under the action of the pressure difference, and does not enter the next stage of blade grooves to continue to be pressurized.

[0004] Therefore, in a vortex vacuum pump, the sealing structure of the upper and lower ends of the impeller is an important factor affecting its gas leakage, working efficiency and stability. Existing impeller end seals usually adopt ordinary labyrinth seals or simple contact seals. Although these structures have a certain sealing effect, they often have problems such as insufficient sealing performance and serious gas leakage under high pressure difference and high speed conditions. When the pump is running, the gas will leak in the labyrinth channel due to the pressure difference. This leakage not only affects the vacuum degree and efficiency of the pump, but also may cause rapid wear of the seal and shorten its life. In addition, some labyrinth seals in the prior art lack the design of complex paths, resulting in limited gas barrier effect. Summary of the invention

[0005] The object of the present invention is to provide an interlaced labyrinth sealing structure and a vortex vacuum pump for a vortex vacuum pump, which form a complex fluid path through staggered concave and convex sealing structures, thereby achieving efficient sealing, significantly reducing the risk of leakage and improving the durability of the equipment.

[0006] The embodiment of the present invention is achieved as follows:

[0007] An embodiment of the present application provides an interlaced labyrinth sealing structure for a vortex vacuum pump, wherein the vortex vacuum pump comprises a volute and an impeller disposed in the volute, wherein the interlaced labyrinth sealing structure comprises a first sealing structure disposed on both side end surfaces of the impeller and a second sealing structure disposed on the inner end surface of the volute, wherein the first sealing structure is opposite to the second sealing structure and is arranged in an interlaced manner to form a concave and convex staggered sealing path.

[0008] Further, based on the aforementioned scheme, the above-mentioned first sealing structure is arranged between the impeller blades and the impeller central axis hole, and the first sealing structure includes a plurality of protrusions arranged at annular intervals; the second sealing structure is opposite to the first sealing structure, and the second sealing structure includes a plurality of grooves arranged at annular intervals, and the protrusions are adapted to be inserted into the grooves.

[0009] Further, based on the above-mentioned solution, the heights of the plurality of protrusions arranged at annular intervals are different, and the recessed depths of the plurality of grooves arranged at annular intervals are different, wherein the relative protrusions and grooves are matched one by one.

[0010] Further, based on the above-mentioned solution, the gap widths between the plurality of protrusions arranged in the above-mentioned annular spacing are different.

[0011] Further, based on the aforementioned solution, the protrusion and the groove are both conical.

[0012] Further, based on the aforementioned solution, the protrusion and the side wall of the groove are coated with a wear-resistant coating.

[0013] Furthermore, based on the above-mentioned solution, the first sealing structure and the second sealing structure are made of wear-resistant material.

[0014] Further, based on the aforementioned solution, the first sealing structure is integrally formed with the impeller, and the second sealing structure is integrally formed with the volute.

[0015] A vortex vacuum pump comprises the staggered labyrinth sealing structure described in any one of the above items.

[0016] Further, based on the above-mentioned solution, a vortex channel is formed between the multiple blades of the impeller, and an annular dust ring is provided on the end surfaces of both sides of the impeller near the bottom of the vortex channel.

[0017] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0018] The present application sets a first sealing structure and a second sealing structure that cooperate with each other. The first sealing structure is set on the end faces on both sides of the impeller, and the second sealing structure is set on the inner end face of the volute. When the impeller and the volute are assembled, the first sealing structure and the second sealing structure are arranged opposite to each other and staggered to form a sealing path with convex and concave staggers, thereby forming a staggered labyrinth sealing structure. The use of a structure in which the impeller and the volute are interlocked and staggered with each other can avoid a straight flow channel between the impeller and the volute, forming a complex fluid path, so as to achieve multiple flow changes and pressure reduction of the gas, thereby achieving the effect of reducing gas leakage, so that the structure can provide a stable sealing effect under high speed and high pressure difference conditions, and significantly improve the efficiency and service life of the vortex vacuum pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a longitudinal cross-sectional schematic diagram of a staggered labyrinth seal structure for a vortex vacuum pump according to an embodiment of the present invention;

[0021] Figure 2 For the present invention Figure 1 The middle part of the structure is enlarged schematic diagram;

[0022] Figure 3 This is a schematic diagram of the structure of an impeller according to an embodiment of the present invention;

[0023] Figure 4 is a schematic longitudinal section diagram of an impeller according to an embodiment of the present invention;

[0024] Figure 5 It is a schematic structural diagram of a volute according to an embodiment of the present invention;

[0025] Figure 6 A schematic diagram of a gas flow path in a vortex vacuum pump according to an embodiment of the present invention;

[0026] Figure 7 It is a schematic diagram comparing the linear changes of the inlet pressure and outlet flow rate of a vortex vacuum pump according to an embodiment of the present invention;

[0027] Figure 8 The figure is a schematic diagram comparing the linear changes of the vacuum degree and the outlet flow rate of a vortex vacuum pump according to an embodiment of the present invention.

[0028] Icon: 1-impeller, 11-first sealing structure, 111-protrusion, 12-dust ring, 2-volute, 21-second sealing structure, 211-groove. DETAILED DESCRIPTION

[0029] The embodiments of the present application are described in detail below in conjunction with the drawings in the embodiments of the present application.

[0030] Please refer to Figure 1-Figure 8 , which is a schematic diagram of the overall structure of the staggered labyrinth seal structure for a vortex vacuum pump,

[0031] The present embodiment provides a staggered labyrinth sealing structure for a vortex vacuum pump. The vortex vacuum pump includes a volute 2 and an impeller 1 arranged in the volute 2. The staggered labyrinth sealing structure includes a first sealing structure 11 arranged on the end surfaces on both sides of the impeller 1 and a second sealing structure 21 arranged on the inner end surface of the volute 2. The first sealing structure 11 and the second sealing structure 21 are opposite to each other and are arranged in an interlaced manner to form a concave and convex staggered sealing path.

[0032] Next, an interlaced labyrinth seal structure for a vortex vacuum pump according to this exemplary embodiment will be further described.

[0033] In some embodiments, reference Figure 1-Figure 5 The above-mentioned staggered labyrinth sealing structure includes a first sealing structure 11 arranged on the end faces of both sides of the impeller 1 and a second sealing structure 21 arranged on the inner end face of the volute 2. The first sealing structure 11 and the second sealing structure 21 are opposite to each other and arranged in an interlaced manner to form a sealing path with convex and concave staggered. By respectively arranging the first sealing structure 11 and the second sealing structure 21 on the end faces of the impeller 1 and the volute 2 that cooperate with each other, so that the two are assembled to form an interlaced staggered sealing structure with convex and concave staggered arrangements, it is possible to change the existing linear leakage flow channel between the impeller 1 and the volute 2, forming a complex fluid path with convex and concave staggered arrangements, thereby realizing multiple flow changes and pressure reduction of the gas, thereby achieving the effect of reducing gas leakage. Among them, the above-mentioned first sealing structure 11 is integrally formed with the impeller 1, and the second sealing structure 21 is integrally formed with the volute 2, so as to improve the sealing performance and improve the structural stability at the same time.

[0034] As a preferred embodiment, the first sealing structure 11 is disposed between the blades of the impeller 1 and the central shaft hole of the impeller 1. The first sealing structure 11 includes a plurality of protrusions 111 arranged at annular intervals. The second sealing structure 21 is opposite to the first sealing structure 11. The second sealing structure 21 includes a plurality of grooves 211 arranged at annular intervals. The protrusions 111 are adapted to be inserted into the grooves 211. The annular protrusions 111 are adapted to the annular grooves 211, and are arranged in a staggered manner from near the center of the shaft hole to the outside to form a plurality of annular sealed chambers. After the gas enters the sealed chamber, it flows in the circumferential direction along the annular sealed chambers in turn, and then crosses the concave-convex structure in the radial direction. In this process, it needs to pass through multiple curved paths and obstructions, realize multiple changes of direction and diversions, and the pressure gradually decreases, and finally achieves an effective sealing effect, which can significantly reduce gas leakage and reduce energy loss. Figure 6 Shown is the fluid path of gas entering the pump body.

[0035] As a preferred embodiment, the heights of the plurality of protrusions 111 arranged at annular intervals are different, and the depths of the plurality of grooves 211 arranged at annular intervals are different, wherein the relative protrusions 111 and grooves 211 are matched one by one. That is, the heights of the concave and convex sealing structures in the radial direction may be inconsistent, and the heights from the area with large gas flow to the area with gradually reduced gas flow may be set to decrease in a step-like manner as needed, and sealed chambers are formed at different heights, so that the kinetic energy loss of the fluid is increased during the flow change process of the gas, and the sealing effect is improved.

[0036] As a preferred embodiment, the gap widths between the plurality of protrusions 111 arranged at annular intervals are different, and the plurality of grooves 211 arranged at annular intervals opposite thereto also have different gap widths. That is, the spacings between the plurality of sealed chambers may be inconsistent, and the sealed chambers in the area with a larger gas flow rate may be arranged more densely as required to increase the gas flow time and gas flow resistance, and to form eddies of different sizes in different sealed chambers, causing different resistances to the gas, thereby increasing the complexity of the sealing structure and improving the sealing effect.

[0037] As a preferred embodiment, the protrusion 111 and the groove 211 may be tapered, which can reduce the direct impact between the fluid and the protrusion 111 or the groove 211 and reduce wear.

[0038] As a preferred embodiment, the sidewalls of the protrusion 111 and the groove 211 may be coated with a wear-resistant coating, such as a ceramic coating or a high-temperature resistant polymer coating, which can reduce the friction between the sealing structure and the fluid and reduce wear.

[0039] As a preferred implementation, the first sealing structure 11 and the second sealing structure 21 may also be made of highly wear-resistant materials, such as corrosion-resistant metals or high-strength alloys, to enhance the stability and life of the structures.

[0040] The present application also provides a vortex vacuum pump, including the above-mentioned staggered labyrinth seal structure. A vortex channel is formed between the multiple blades of the impeller 1, and an annular dust ring 12 is provided on both side surfaces of the impeller 1 near the bottom of the vortex channel. The dust ring 12 can play a dustproof and sealing role, thereby improving the dustproof sealing performance of the pump body. Figure 4 shown.

[0041] The above-mentioned staggered labyrinth seal structure is particularly suitable for vortex vacuum pumps with high speed and high pressure difference. Through the sealing path and material selection designed above, the sealing performance of the pump can be significantly improved, gas leakage can be reduced, and the service life of the equipment can be extended.

[0042] In a specific implementation, referring to Figure 7 and Figure 8 The performance test of the sealing structure when applied to the vortex vacuum pump is compared with the performance test of other sealing conditions, such as Figure 7 The figure shows a linear graph of the vacuum pump inlet pressure and outlet flow rate, as Figure 8 The figure shows a linear graph of gas vacuum and outlet flow, which are tested and compared under four sealing conditions, including the vacuum pump completely leak-free state, the state of applying the sealing structure of the present application, the no-seal state, and the simulation experiment of the sealing structure of the present application. The test results show that under the same working conditions, the sealing design of the present invention can reduce the leakage rate by more than 30% and improve the stability and durability of the equipment.

[0043] In addition, unless otherwise expressly specified or limited, in the embodiments of the present application, if the terms "installation" and "connection" appear, they should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. If the terms "upper", "lower", "left", "right", "inner", "outer", "side" and other directional terms appear, they are only with reference to the direction of the accompanying drawings or the orientation in which the product is usually placed when in use. They are only for the purpose of clearly describing the present application, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as a limitation on the present application. The terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance; "multiple" means at least two. In the embodiments of the present application, the limitations of relative positional relationships such as parallel, vertical, and aligned are all for the current technological level, rather than absolutely strict limitations. A small amount of deviation is allowed, and approximately parallel, approximately vertical, approximately aligned, etc. are all acceptable. For example, A and B are parallel, which means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 degrees and 10 degrees.

[0044] The above are only some embodiments and implementation methods of the present application. The protection scope of the present application is not limited thereto. In the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Any combination of features in different embodiments is also within the protection scope of the present application. Any changes or substitutions that can be easily thought of by any technician familiar with the field within the technical scope disclosed in the present application should be covered within the protection scope of the present application.

Claims

1. An interlaced labyrinth seal structure for a vortex vacuum pump, the vortex vacuum pump comprising a volute and an impeller disposed in the volute, characterized in that: The staggered labyrinth sealing structure includes a first sealing structure arranged on the end surfaces of both sides of the impeller and a second sealing structure arranged on the inner end surface of the volute. The first sealing structure and the second sealing structure are opposite to each other and arranged staggered to form a concave and convex staggered sealing path.

2. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 1, characterized in that: The first sealing structure is arranged between the impeller blades and the impeller central axis hole, and the first sealing structure includes a plurality of protrusions arranged at annular intervals; the second sealing structure is opposite to the first sealing structure, and the second sealing structure includes a plurality of grooves arranged at annular intervals, and the protrusions are adapted to be inserted into the grooves.

3. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 2, characterized in that: The heights of the plurality of protrusions arranged at annular intervals are different, and the recessed depths of the plurality of grooves arranged at annular intervals are different, wherein the relative protrusions and grooves are matched one by one.

4. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 3, characterized in that: The gap widths between the plurality of protrusions arranged in an annular manner are different.

5. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 2, characterized in that: The protrusion and the groove are both tapered.

6. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 2, characterized in that: The protrusion and the sidewalls of the groove are coated with a wear-resistant coating.

7. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 1, characterized in that: The first sealing structure and the second sealing structure are made of wear-resistant material.

8. The staggered labyrinth seal structure for a vortex vacuum pump according to claim 1, characterized in that: The first sealing structure is integrally formed with the impeller, and the second sealing structure is integrally formed with the volute.

9. A vortex vacuum pump, characterized in that: It comprises the staggered labyrinth sealing structure as described in any one of claims 1 to 8.

10. The vortex vacuum pump according to claim 9, characterized in that: A vortex channel is formed between the multiple blades of the impeller, and an annular dust ring is arranged on the end surfaces of both sides of the impeller near the bottom of the vortex channel.

Images