Vane pump

Abstract

The utility model discloses a vane pump. The vane pump comprises a pump body, an impeller and a sealing device, the sealing device comprises a movable ring, a static ring, a positioning plate, a telescopic pipe and a guide hole; the moving ring is mounted on a front cover plate of the impeller or on the suction inlet side of the blade; the guide hole is formed in the suction side of the pump body, the guide hole and the impeller are coaxially arranged, and the static ring, the telescopic pipe and the positioning plate are sequentially arranged in the guide hole from inside to outside; one end of the telescopic pipe is fixed to the positioning plate, the other end of the telescopic pipe is fixed to the static ring, the static ring is in clearance fit with the guide hole, and the static ring can move in the axis direction of the guide hole and can make contact with the movable ring; the positioning plate is fixed on the pump body; and a medium enters an impeller suction inlet from the radial inner sides of the positioning plate, the telescopic pipe and the static ring in sequence. According to the vane pump, internal leakage of media can be remarkably reduced, the sealing effect is better, the service life of the sealing structure is longer, and the vane pump is more convenient to maintain.

Description

Technical Field

[0001] This utility model belongs to the field of vane pump manufacturing, and specifically relates to a vane pump. Background Technology

[0002] Centrifugal pumps, including centrifugal pumps, mixed-flow pumps, and axial-flow pumps, are the most common fluid transport equipment. During operation, the rotating impeller draws the medium in through the suction inlet, and the blades perform work on the medium, accelerating it and sending it into the plenum chamber of the pump body. Because the pressure in the plenum chamber is higher than the pressure at the suction inlet, the medium in the plenum chamber leaks through the gap between the impeller and the pump body back to the suction inlet. This is called internal leakage, and internal leakage leads to a decrease in the efficiency of the centrifugal pump. Therefore, to improve the efficiency of centrifugal pumps, many existing centrifugal pumps are designed with sealing rings to reduce internal leakage. Since the sealing ring and the pump body have a clearance fit, the size of this clearance is limited by factors such as machining accuracy and mechanical operation accuracy, making internal leakage a significant factor limiting the improvement of centrifugal pump efficiency.

[0003] To address this issue, three patents / patent applications have been proposed: Patent CN114738311 B discloses a "leak-free centrifugal pump"; Patent CN2150371Y discloses a "pump inlet ring sealing structure"; and Patent CN116696784 A discloses a "shipboard mud and sand pump with an inlet sealing ring." All three patents / patent applications describe a structure similar to a mechanical seal friction pair at the impeller's sealing ring location. This involves using an elastic element like a spring to press the sealing ring, thus preventing leakage of the medium from the high-pressure area of ​​the pressure chamber to the low-pressure area at the inlet. While these structures theoretically solve the internal leakage problem of centrifugal pumps, in actual operation, the spring force is difficult to control, and the lifespan of the friction pair is greatly affected by the spring force. Specifically, a large spring force significantly shortens the lifespan of the friction pair; conversely, a small spring force allows the medium pressure to force open the friction pair, resulting in a suboptimal sealing effect. Secondly, the spring force changes continuously with the wear of the friction pair. This leads to significant changes in friction and sealing effect when the friction pair experiences a certain level of wear, making it prone to seal failure due to wear. Furthermore, the short lifespan of the friction pair necessitates periodic replacement for maintenance. The aforementioned solutions are structurally complex and require disassembly of the pump body for replacement and maintenance, making maintenance extremely inconvenient. Therefore, the above-mentioned technical solutions have failed to gain widespread adoption in industrial applications due to these unresolved problems. Utility Model Content

[0004] To overcome the shortcomings of the existing technology, this utility model provides a vane pump that can significantly reduce internal leakage of the medium, has a better sealing effect, a longer service life of the sealing structure, and is more convenient to maintain.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is:

[0006] A vane pump includes a pump body, an impeller, and a sealing device disposed between the pump body and the impeller. The sealing device includes a rotating ring, a stationary ring, a positioning plate, a telescopic tube, and a guide hole. The rotating ring is mounted on the front cover plate of the impeller or on the suction inlet side of the vane. The guide hole is disposed on the suction side of the pump body and coaxially with the impeller. The stationary ring, telescopic tube, and positioning plate are sequentially disposed within the guide hole from the inside to the outside. One end of the telescopic tube is fixed to the positioning plate, and the other end is fixed to the stationary ring. The stationary ring and the guide hole are clearance-fitted, allowing the stationary ring to move along the axial direction of the guide hole and contact the rotating ring. The positioning plate is fixed to the pump body. The medium sequentially enters the impeller suction inlet from the radially inner side of the positioning plate, the telescopic tube, and the stationary ring.

[0007] More preferably, the positioning plate, the telescopic tube, and the stationary ring are an integral structure, and the integral structure can be installed into the guide hole along the suction direction of the impeller.

[0008] More preferably, the positioning plate is provided with a positioning flange at the end away from the impeller; the pump body is provided with a matching positioning stop at a position corresponding to the positioning flange; the positioning stop and the guide hole are coaxially arranged.

[0009] More preferably, the pump body is provided with a channel or pipe connecting the guide hole and the high-pressure zone / outlet of the pressure chamber. The high-pressure medium injected into the guide hole causes the stationary ring to drive the telescopic tube to move axially until the stationary ring contacts the moving ring.

[0010] More preferably, the axial length of the stationary ring is 3-10 times the axial length of the rotating ring, and the hardness of the stationary ring is less than that of the rotating ring.

[0011] More preferably, the stationary ring is provided with a plurality of water holes extending along its axial direction and penetrating both sides of the stationary ring; the stationary ring is provided with a water groove communicating with the water holes on its end face that contacts the moving ring.

[0012] More preferably, an inlet flange is provided on the outer end of the pump body's suction port, and the outer end face of the positioning plate is flush with the end face of the inlet flange.

[0013] More preferably, an inlet flange is provided on the outer end of the pump body's suction port, and a high-pressure water hole is provided on the inlet flange for connecting the high-pressure zone / outlet of the pressure chamber; the high-pressure water hole is located on the side of the inlet flange away from the impeller, and the axial direction of the high-pressure water hole is perpendicular to the axial direction of the pump body.

[0014] More preferably, the telescopic tube is a corrugated tube.

[0015] More preferably, an elastic element for pushing the stationary ring toward the moving ring is provided between the positioning plate and the stationary ring. One end of the elastic element acts on the positioning plate and the other end is positioned on the stationary ring. The elastic element can be removed from the guide hole in the opposite direction to the suction direction of the impeller.

[0016] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0017] The vane pump of this invention has a simple structure. It can maintain the coaxiality and parallelism between the stationary ring and the rotating ring by using the guide hole. At the same time, while ensuring the cavitation performance of the vane pump of this invention, the diameter of the stationary ring is minimized, thereby reducing the relative frictional linear velocity between the rotating ring and the stationary ring, which is beneficial to improving the service life of both. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the first specific embodiment of the vane pump of this utility model.

[0019] Figure 2 This is a sectional view of the pump body.

[0020] Figure 3 for Figure 1 A partial view at point A.

[0021] Figure 4 This is a cross-sectional view of the second specific embodiment of the vane pump of this utility model.

[0022] Figure 5 for Figure 4 A partial view at point B.

[0023] Figure 6 This is a three-dimensional sectional view of the stationary ring.

[0024] Figure 7 This is a cross-sectional view of the third specific embodiment of the vane pump of this utility model.

[0025] In the diagram: 1-Pump body, 101-Rear pump body, 102-Front pump body, 103-Inlet flange, 104-High-pressure water hole, 2-Impeller, 3-High-pressure water pipe, 4-Guide hole, 5-Positioning plate, 501-Positioning flange, 6-Stationary ring, 601-Water hole, 602-Water guide groove, 7-Dynamic ring, 8-Expansion pipe, 9-Spring, 10-Dark water channel. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0027] Example 1

[0028] like Figures 1-3 As shown, the vane pump of this utility model includes a pump body 1, an impeller 2, and a sealing structure disposed between the pump body 1 and the impeller 2. The sealing device includes a rotating ring 7, a stationary ring 6, a positioning plate 5, a telescopic tube 8, and a guide hole 4. The rotating ring 7 is mounted on the front cover plate of the impeller 2. The guide hole 4 is disposed on the suction side of the pump body 1 and coaxial with the impeller 2. The stationary ring 6, the telescopic tube 8, and the positioning plate 5 are sequentially disposed within the guide hole 4 from the inside to the outside. One end of the telescopic tube 8 is fixed to the positioning plate 5, and the other end is fixed to the stationary ring 6. The stationary ring 6 and the guide hole 4 are in clearance fit, allowing the stationary ring 6 to move axially along the guide hole 4 and to contact the rotating ring 7. The positioning plate 5 is fixed to the pump body 1. The medium enters the impeller suction port sequentially from the radially inner side of the positioning plate 5, the telescopic tube 8, and the stationary ring 6. The axial length of the stationary ring 6 is greater than the thickness of the rotating ring 7.

[0029] Because the guide hole 4 is located on the suction pipe on the suction side of the pump body 1, it has a relatively long axial space. Therefore, the axial length of the stationary ring 6 can be set to be large, allowing the stationary ring 6 to achieve a longer service life. The structure in which the medium enters the impeller suction port sequentially from the radially inner side of the positioning plate 5, the telescopic pipe 8, and the stationary ring 6 can minimize the radial dimension of the stationary ring 6 while meeting cavitation performance requirements. This reduces the frictional linear velocity between the friction pairs, thereby extending the service life of the friction pairs.

[0030] like Figures 1-3 As shown, the telescopic tube 8 and the stationary ring 6, and the positioning plate 5 and the telescopic tube 8 are connected to form an integral structure. The integral structure can be installed into the guide hole 4 along the suction direction of the impeller 2. This structure allows for the replacement of easily damaged parts such as the stationary ring 6, the telescopic tube 8, and the positioning plate 5 without removing the pump body 1, thereby greatly reducing the workload during maintenance.

[0031] like Figures 1-3As shown, the positioning plate 5 is provided with a positioning flange 501 at the end away from the impeller 2; the pump body 1 is provided with a positioning stop at the position corresponding to the positioning flange 501; the positioning stop and the guide hole 4 are coaxially arranged, and the positioning stop is located on the suction port side of the pump body 1 and at the end away from the impeller 2; this structure can make the stationary ring 6 obtain the maximum axial dimension without increasing the axial dimension of the pump body 1, thereby improving its service life and extending its maintenance cycle.

[0032] like Figures 1-3 As shown, the pump body 1 is provided with a high-pressure water pipe 3 for connecting the guide hole 4 and the high-pressure zone of the pressure chamber; the pressure of the high-pressure medium injected into the guide hole 4 can push the stationary ring 6 and the telescopic pipe 8 connected thereto to move towards the moving ring 7; compared with the structure of pressing the friction pair by spring force in the prior art, in this embodiment there will be no significant change in contact force due to wear of the friction pair (composed of stationary ring 6 and moving ring 7), thereby preventing the rapid failure of the sealing structure due to wear of the friction pair.

[0033] In this embodiment, the stationary ring 6 is made of HDPE with an axial length of 44mm; the rotating ring 7 is made of tungsten carbide alloy, which has a much higher hardness than the stationary ring 6, and an axial length of 7mm. The former is 6.3 times thicker than the latter, which allows the rotating ring 7 to have a longer service life. Furthermore, due to its larger axial length, the stationary ring 6 has a significantly longer service life compared to existing technologies. It is also easier to replace and promote. Generally, the axial length of the stationary ring 6 should be 3-10 times that of the rotating ring 7. If the stationary ring 6 is too thin, its service life will be short, and the maintenance cycle will be short; conversely, if the thickness is too small, the axial dimension of the pump body 1 will be too large, resulting in a significant increase in manufacturing costs.

[0034] like Figures 1-3 As shown, an inlet flange 103 is provided on the outer end of the suction port of the pump body 1, and the outer end face of the positioning plate 501 is flush with the end face of the inlet flange 103. This structure can use the flange of the suction port that is matched with the inlet flange 103 to press the positioning plate 5, which not only simplifies the structure of the vane pump, but also saves its manufacturing cost.

[0035] like Figures 1-3 As shown, the high-pressure water hole 104 for installing the high-pressure water pipe 3 is located in the pump body 1 on the side close to the inlet flange 103 and away from the impeller 2, and the axial direction of the high-pressure water hole 104 is perpendicular to the axial direction of the pump body 1.

[0036] like Figures 1-3 As shown, the telescopic pipe 8 is a corrugated pipe.

[0037] See Figures 1-3 The working principle of the vane pump in this embodiment is as follows:

[0038] In this embodiment, during operation, high-pressure water generated on the pipe at the outlet of pump body 1 enters the guide hole 4 through high-pressure water pipe 3 and high-pressure water hole 104. Because the friction end of the stationary ring 6 (i.e., the end near the moving ring 7) leaks towards the suction port of pump body 1, the pressure at the friction end of the stationary ring 6 is necessarily lower than the pressure at its connection end with the bellows (i.e., the end away from the moving ring 7). The water pressure entering the guide hole 4 pushes the stationary ring 6 and the bellows connected to it to move axially towards the moving ring 7 along the guide hole 4, causing the stationary ring 6 and the moving ring 7 to come into contact, thereby blocking the leakage of the high-pressure medium from the pressure chamber to the suction port of pump body 1, thus improving the efficiency of the vane pump in this embodiment. At this time, because the water pressure on the outside of the friction pair is higher than the water pressure on the inside, the high-pressure medium will permeate the surface of the friction pair, thereby lubricating and cooling the friction pair, thus improving its lifespan.

[0039] Example 2

[0040] like Figures 4-6 As shown, the main differences between this embodiment and Embodiment 1 are:

[0041] The pump body 1 is provided with a hidden water channel 10, one end of which is connected to the high-pressure zone of the pressure chamber, and the other end is connected to the axial outer side of the guide hole 4. The stationary ring 6 is provided with 20 water holes 601, which extend along the axial direction of the stationary ring 6. The friction end of the stationary ring 6 is provided with a water groove 602 that communicates with the water holes 601. By providing a number of water holes 601 that communicate with the friction end of the stationary ring 6, the high-pressure medium can be injected into the friction surface between the moving ring 7 and the stationary ring 6 through the water holes 601, thereby forming a structure similar to a hydrostatic thrust bearing, which greatly improves the lubrication condition at the friction surface and can further improve the service life of the friction pair.

[0042] like Figures 4-6 As shown, a water groove 602 communicating with the water hole 601 is provided on the friction end of the stationary ring 6. The water groove 602 can further improve the lubrication of the friction pair, thereby increasing the service life of the friction pair.

[0043] like Figures 4-6 As shown, the pump body 1 is composed of a front pump body 102 and a rear pump body 101, which allows for the replacement of corresponding parts according to wear conditions, thereby reducing manufacturing costs.

[0044] like Figures 4-6As shown, since the stationary ring 6 is made of tin bronze and the impeller 2 is made of wear-resistant alloy, it has good wear resistance. Therefore, the moving ring 7 is directly machined on the blank of the impeller 2. At this time, the axial length of the moving ring 7 is the axial length of the impeller 2 at the position corresponding to the stationary ring 6.

[0045] In this embodiment, the axial length of the moving ring 7 is 14 mm, and the axial length of the stationary ring 6 is 44 mm, the latter being 3.1 times that of the former.

[0046] like Figures 4-6 As shown, the working principle of the vane pump in this embodiment is as follows:

[0047] When the vane pump in this embodiment is working, high-pressure water enters the water tank 602 through the underground water channel 10 and water hole 601. Since the water pressure at the guide hole 4 is higher than the pressure at the friction pair, this pressure will push the stationary ring 6 and the moving ring 7 to contact each other to achieve a seal. When the friction end face of the stationary ring 6 contacts the moving ring 7, the pressure at the water tank 602 increases, pushing the stationary ring 6 away from the moving ring 7 in the opposite direction, causing the high-pressure medium to leak to the suction port of the pump body 1. This, in turn, causes the water pressure at the delivery water tank 602 to decrease, making the pressure at the delivery guide hole 4 higher than the pressure at the friction pair. This pressure will again push the delivery stationary ring 6 and the delivery moving ring 7 to contact each other to achieve a seal. This is equivalent to causing the stationary ring 6 to dynamically float under the action of the water pressure at both ends, thereby maintaining an appropriate leakage of the friction pair while meeting the cooling and lubrication requirements of the friction pair.

[0048] In addition, to prevent excessive axial floating of the stationary ring 6, four springs 9 are added in this embodiment. The main function of the springs 9 is to dampen the floating of the stationary ring 6, so they do not need to exert a large thrust on the seal of the friction pair. Therefore, the spring force of the springs 9 can be designed to be small to improve the life of the friction pair. One end of the spring 9 acts on the stationary ring 6, and the other end acts on the positioning plate 5, so that it can act in the opposite direction of the impeller 2's suction direction (i.e., Figure 4 (From right to left) Remove the spring 9 from the guide hole 4. During maintenance, it is not necessary to remove the pump body 1, which can significantly reduce the amount of maintenance work.

[0049] Example 3

[0050] like Figure 7 As shown, the main difference between this embodiment and the previous one is that:

[0051] The impeller 2 is a semi-open impeller; the moving ring 7 is disposed on the suction port side of the blades of the impeller 2, and the moving ring 7 is directly machined on the blank of the impeller 2 to reduce manufacturing costs.

[0052] Finally, in the above three embodiments, the medium (e.g., water) in the components such as the high-pressure water hole 104, high-pressure water pipe 3, water inlet 601, underground water channel 10, and water guide trough 602 is only for ease of description and not a limitation on the medium. The same effect can be achieved by changing it to other liquid media such as oil or alcohol.

[0053] The above are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited to the above content. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A vane pump, characterized in that, The pump includes a pump body, an impeller, and a sealing device disposed between the pump body and the impeller. The sealing device includes a rotating ring, a stationary ring, a positioning plate, a telescopic tube, and a guide hole. The rotating ring is mounted on the front cover plate of the impeller or on the suction side of the blades. The guide hole is disposed on the suction side of the pump body and coaxially with the impeller. The stationary ring, telescopic tube, and positioning plate are sequentially disposed within the guide hole from the inside to the outside. One end of the telescopic tube is fixed to the positioning plate, and the other end is fixed to the stationary ring. The stationary ring and the guide hole are clearance-fitted, allowing the stationary ring to move along the axial direction of the guide hole and to contact the rotating ring. The positioning plate is fixed to the pump body. The medium sequentially enters the impeller suction port from the radially inner side of the positioning plate, the telescopic tube, and the stationary ring.

2. The vane pump according to claim 1, characterized in that, The positioning plate, the telescopic tube, and the stationary ring are an integral structure, which can be installed into the guide hole along the suction direction of the impeller.

3. The vane pump according to claim 1, characterized in that, The positioning plate has a positioning flange at the end away from the impeller; the pump body has a matching positioning stop at a position corresponding to the positioning flange; the positioning stop and the guide hole are coaxially arranged.

4. The vane pump according to claim 1, characterized in that, The pump body is provided with a channel or pipe connecting the guide hole and the high-pressure zone / outlet of the pressure chamber. The high-pressure medium injected into the guide hole causes the stationary ring to drive the telescopic tube to move axially until the stationary ring contacts the moving ring.

5. The vane pump according to any one of claims 1-4, characterized in that, The axial length of the stationary ring is 3-10 times the axial length of the rotating ring, and the hardness of the stationary ring is less than that of the rotating ring.

6. The vane pump according to any one of claims 1-4, characterized in that, The stationary ring is provided with a plurality of water holes extending along its axial direction and penetrating both sides of the stationary ring; the stationary ring is provided with a water groove communicating with the water holes on its end face that contacts the moving ring.

7. The vane pump according to any one of claims 1-4, characterized in that, An inlet flange is provided on the outer end of the pump body's suction port, and the outer end face of the positioning plate is flush with the end face of the inlet flange.

8. The vane pump according to claim 4, characterized in that, An inlet flange is provided on the outer end of the pump body's suction port, and a high-pressure water hole is provided on the inlet flange for connecting the high-pressure zone / outlet of the pressure chamber; the high-pressure water hole is located on the side of the inlet flange away from the impeller, and the axial direction of the high-pressure water hole is perpendicular to the axial direction of the pump body.

9. The vane pump according to claim 1, characterized in that, The telescopic tube is a corrugated pipe.

10. The vane pump according to claim 1 or 4, characterized in that, An elastic element for pushing the stationary ring toward the moving ring is also provided between the positioning plate and the stationary ring. One end of the elastic element acts on the positioning plate, and the other end is positioned on the stationary ring. The elastic element can be removed from the guide hole in the opposite direction to the suction direction of the impeller.

Images