Vane pump

Abstract

The invention discloses a vane pump which 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 a medium can be remarkably reduced, the sealing effect is better, the service life of the sealing structure is longer, and maintenance is more convenient.

Description

Technical Field

[0001] The invention belongs to the field of vane pump manufacturing, and in particular relates to a vane pump. Background Art

[0002] Vane pumps include centrifugal pumps, diagonal flow pumps and axial flow pumps, and are the most common fluid conveying equipment. When the vane pump is working, the impeller rotates to suck the medium from the suction port, and the blades work on the medium, thereby accelerating the medium and sending it into the pressure chamber of the pump body. Since the pressure in the pressure chamber is higher than the pressure at the suction port, the medium in the pressure chamber will leak to the suction port through the gap between the impeller and the pump body. This situation is called internal leakage, and internal leakage will cause the working efficiency of the vane pump to decrease. Therefore, in order to improve the efficiency of the vane pump, many existing vane pumps are designed with sealing rings to reduce internal leakage. Since there is a clearance fit between the sealing ring and the pump body, the size of the clearance will be limited by many aspects such as machining accuracy and mechanical operation accuracy, which also makes internal leakage an important factor limiting the improvement of the working efficiency of the vane pump.

[0003] In order to solve this problem, the invention patent with the authorized patent number CN114738311 B discloses "a leak-free centrifugal pump", the utility model patent with the authorized patent number CN2150371Y discloses "a pump suction ring sealing structure", and the invention patent application with the application publication number CN116696784 A discloses "a ship-used mud and sand pump with an inlet sealing ring". The above three patents / patent applications all disclose that a structure similar to a mechanical seal friction pair is set at the position of the sealing ring of the impeller, and the sealing ring is compressed by elastic parts such as springs, and the medium is blocked from leaking from the high-pressure area of ​​the pressure chamber to the low-pressure area at the suction port through the friction pair. The above structure can theoretically solve the internal leakage problem of the vane pump, but in the actual operation process, the size of the spring force is difficult to control, and the life of the friction pair is greatly affected by the spring force. When the spring force is large, the life of the friction pair will be greatly shortened; when the spring force is small, the medium pressure is enough to push open the friction pair, which will cause the sealing effect to fail to meet expectations. Secondly, the spring force changes continuously with the continuous wear of the friction pair, which results in a significant change in friction force and sealing effect when the friction pair is worn to a certain extent, which easily leads to seal failure due to wear. At the same time, due to the short life of the friction pair, the friction pair needs to be replaced regularly for maintenance. The above scheme has a complex structure and requires the pump body to be disassembled before replacement and maintenance, which is extremely inconvenient. Therefore, the above technical scheme has not been promoted in industrial applications because the above problems are difficult to solve. Summary of the invention

[0004] In order to overcome the deficiencies in the prior art, the present invention provides a vane pump, which can significantly reduce internal leakage of a medium, has a better sealing effect, a longer service life of a sealing structure, and is more convenient to maintain.

[0005] The technical solution of the present invention to solve the above technical problems is:

[0006] A vane pump comprises a pump body, an impeller and a sealing device arranged between the pump body and the impeller, wherein the sealing device comprises a dynamic ring, a static ring, a positioning plate, a telescopic tube and a guide hole; the dynamic ring is mounted on the front cover plate of the impeller or on the suction port side of the blade; the guide hole is arranged on the suction side of the pump body and is coaxial with the impeller, and the static ring, the telescopic tube and the positioning plate are arranged in the guide hole in sequence from the inside to the outside; one end of the telescopic tube is fixed on the positioning plate, and the other end is fixed on the static ring, the static ring and the guide hole are clearance-fitted, the static ring can move along the axial direction of the guide hole and can contact the dynamic ring; the positioning plate is fixed on the pump body; the medium enters the impeller suction port from the radial inner side of the positioning plate, the telescopic tube and the static ring in sequence.

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

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

[0009] Preferably, the pump body is provided with a channel or pipe connecting the guide hole and the high-pressure area / water outlet of the water pressure chamber, and the high-pressure medium injected into the guide hole causes the static ring to drive the telescopic tube to move axially until the static ring contacts the dynamic ring.

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

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

[0012] More preferably, an inlet flange is provided on the end portion outside the suction port of the pump body, and the end surface outside the positioning plate is flush with the end surface of the inlet flange.

[0013] More preferably, an inlet flange is provided on the end portion outside the suction port of the pump body, and a high-pressure water hole for connecting to the high-pressure area / water outlet of the water pressure chamber is provided on the inlet flange; the high-pressure water hole is arranged 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 bellows.

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

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0017] The vane pump of the present invention has a simple structure and can utilize guide holes to maintain the coaxiality and parallelism between the stationary ring and the dynamic ring. At the same time, while ensuring the cavitation performance of the vane pump of the present invention, the diameter of the stationary ring is minimized, thereby reducing the relative friction linear velocity between the dynamic ring and the stationary ring, which is beneficial to increasing the service life of both. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional view of a first specific embodiment of the vane pump of the present invention.

[0019] Figure 2 A cross-sectional view of the pump body.

[0020] Figure 3 for Figure 1 Partial view at A.

[0021] Figure 4 It is a cross-sectional view of a second specific embodiment of the vane pump of the present invention.

[0022] Figure 5 for Figure 4 Partial view at B.

[0023] Figure 6 It is a three-dimensional cross-sectional view of the static ring.

[0024] Figure 7 It is a cross-sectional view of a third specific embodiment of the vane pump of the present invention.

[0025] In the figure: 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-static ring, 601-water hole, 602-water guide groove, 7-dynamic ring, 8-telescopic tube, 9-spring, 10-hidden water channel. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0027] Example 1

[0028] like Figure 1-Figure 3 As shown, the vane pump of the present invention comprises a pump body 1, an impeller 2 and a sealing structure arranged between the pump body 1 and the impeller 2, wherein the sealing device comprises a dynamic ring 7, a static ring 6, a positioning plate 5, a telescopic tube 8 and a guide hole 4; the dynamic ring 7 is mounted on the front cover plate of the impeller 2; the guide hole 4 is arranged on the suction side of the pump body 1 and is coaxial with the impeller 2, the static ring 6, the telescopic tube 8 and the positioning plate 5 are arranged in the guide hole 4 from the inside to the outside, one end of the telescopic tube 8 is fixed on the positioning plate 5, and the other end is fixed on the static ring 6, the static ring 6 and the guide hole 4 are clearance-fitted, the static ring 6 can move axially along the guide hole 4 and can contact the dynamic ring 7; the positioning plate 5 is fixed on the pump body 1; the medium enters the impeller suction port from the radial inner side of the positioning plate 5, the telescopic tube 8 and the static ring 6 in turn; the axial thickness dimension of the static ring 6 is greater than the thickness dimension of the dynamic ring 7.

[0029] Since the guide hole 4 is arranged on the suction pipe on the suction port side of the pump body 1 and has a long axial space, the axial thickness dimension of the stationary ring 6 can be set larger, so that the stationary ring 6 can obtain a longer service life. The structure in which the medium enters the impeller suction port from the positioning plate 5, the telescopic tube 8 and the radial inner side of the stationary ring 6 in sequence can enable the stationary ring 6 to obtain the minimum radial dimension while satisfying the cavitation performance, thereby reducing the friction linear velocity between the friction pairs and extending the service life of the friction pairs.

[0030] like Figure 1-Figure 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, and the integral structure can be installed into the guide hole 4 along the suction direction of the impeller 2; this structure can replace the stationary ring 6, the telescopic tube 8, the positioning plate 5 and other vulnerable parts without dismantling the pump body 1, thereby greatly reducing the workload during maintenance.

[0031] like Figure 1-Figure 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 a position corresponding to the positioning flange 501; the positioning stop and the guide hole 4 are coaxially arranged, and the positioning stop is arranged on the suction port side of the pump body 1 and away from the end of the impeller 2; this structure can enable the static ring 6 to obtain the maximum axial dimension without increasing the axial dimension of the pump body 1, thereby increasing its service life and extending its maintenance cycle.

[0032] like Figure 1-Figure 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 area of ​​the water pressure chamber; the pressure of the high-pressure medium injected into the guide hole 4 can push the static ring 6 and the telescopic tube 8 connected thereto to move toward the dynamic ring 7; compared with the structure of the prior art in which the friction pair is compressed by spring force; in this embodiment, there will be no significant change in contact force due to wear of the friction pair (composed of the static ring 6 and the dynamic ring 7), thereby preventing the rapid failure of the sealing structure due to wear of the friction pair.

[0033] In this embodiment, the material of the stationary ring 6 is HDPE, and the axial thickness is 44mm; the material of the dynamic ring 7 is tungsten carbide alloy, which has a much higher hardness than the stationary ring 6 and an axial thickness of 7mm; the thickness of the former is 6.3 times that of the latter, so that the dynamic ring 7 has a longer life. In addition, due to its large axial thickness, the service life of the stationary ring 6 can be significantly improved compared with the prior art. At the same time, because it is easy to replace and popularize, in general, the axial thickness of the stationary ring 6 is preferably 3-10 times the axial thickness of the dynamic ring 7; because the thickness of the stationary ring 6 is too small, its life is short and the maintenance cycle is short; otherwise, the axial size of the pump body 1 will be too large, resulting in too much increase in manufacturing costs.

[0034] like Figure 1-Figure 3 As shown, an inlet flange 103 is provided on the end portion of the outer side of the suction port of the pump body 1, and the end face of the outer side 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 matched with the inlet flange 103 to press the positioning plate 5 tightly, which can not only simplify the structure of the vane pump, but also save its manufacturing cost.

[0035] like Figure 1-Figure 3 As shown, the high-pressure water hole 104 for installing the high-pressure water pipe 3 is arranged in the pump body 1 on a 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 Figure 1-Figure 3 As shown, the telescopic tube 8 is a bellows.

[0037] See also Figure 1-Figure 3 , the working principle of the vane pump of this embodiment is:

[0038] When the vane pump of this embodiment is in operation, the high-pressure water generated on the pipeline at the outlet of the pump body 1 enters the guide hole 4 through the high-pressure water pipe 3 and the high-pressure water hole 104; since the friction end of the static ring 6 (i.e., the end close to the dynamic ring 7) leaks toward the suction port of the pump body 1, the pressure at the friction end of the static ring 6 must be lower than the pressure at the connection end between it and the bellows (i.e., the end away from the dynamic ring 7); the water pressure entering the guide hole 4 will push the static ring 6 and the bellows connected thereto to move toward the dynamic ring 7 along the axial direction of the guide hole 4, so that the static ring 6 and the dynamic ring 7 come into contact, thereby blocking the leakage of the high-pressure medium in the water pressure chamber to the suction port of the pump body 1, so that the efficiency of the vane pump of this embodiment is improved. At this time, since the water pressure on the outside of the friction pair is higher than the water pressure on the inside, the high-pressure medium will penetrate through the surface of the friction pair, thereby lubricating and cooling the friction pair, thereby improving the life of the friction pair.

[0039] Example 2

[0040] like Figure 4-Figure 6 As shown, the differences between this embodiment and embodiment 1 are mainly as follows:

[0041] The pump body 1 is provided with a hidden water channel 10, one end of which is connected to the high-pressure area of ​​the water pressure chamber, and the other end is connected to the axial outer side of the guide hole 4; 20 water holes 601 are provided on the static ring 6, and the water holes 601 extend along the axial direction of the static ring 6; a water trough 602 connected to the water holes 601 is provided on the friction end of the static ring 6; by providing a plurality of water holes 601 connected to the friction end of the static ring 6, the high-pressure medium can be injected into the friction surface between the moving ring 7 and the static ring 6 through the water holes 601, thereby forming a structure similar to a static thrust bearing, which greatly improves the lubrication condition at the friction surface, thereby further improving the life of the friction pair.

[0042] like Figure 4-Figure 6 As shown, a water tank 602 connected to the water hole 601 is provided on the friction end of the stationary ring 6. The water tank 602 can further improve the lubrication condition of the friction pair, thereby increasing the service life of the friction pair.

[0043] like Figure 4-Figure 6 As shown, the pump body 1 is composed of a front pump body 102 and a rear pump body 101, so that corresponding parts can be replaced according to wear conditions to reduce manufacturing costs.

[0044] like Figure 4-Figure 6As shown, since the material of the stationary ring 6 is tin bronze and the impeller 2 is made of wear-resistant alloy, it has good wear resistance; therefore, the dynamic ring 7 is directly processed on the blank of the impeller 2. At this time, the axial thickness of the dynamic ring 7 is the axial thickness of the impeller 2 at the corresponding position of the stationary ring 6.

[0045] In this embodiment, the axial thickness of the dynamic ring 7 is 14 mm, and the axial thickness of the static ring 6 is 44 mm, the latter being 3.1 times of the former.

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

[0047] When the vane pump of this embodiment is working, high-pressure water enters the water tank 602 through the dark water channel 10 and the water hole 601. Since the water pressure at the guide hole 4 is higher than the pressure at the friction pair, the pressure will push the static ring 6 and the dynamic ring 7 to contact to achieve sealing; when the friction end surface of the static ring 6 and the dynamic ring 7 are in contact, the pressure at the water tank 602 increases, and the static ring 6 is pushed away from the dynamic ring 7 in the opposite direction, so that the high-pressure medium leaks to the suction port of the pump body 1, which in turn causes the water pressure at the delivery water tank 602 to decrease, so that the pressure at the delivery guide hole 4 is higher than the pressure at the friction pair, and the pressure will again push the delivery static ring 6 and the delivery dynamic ring 7 to contact to achieve sealing; this is equivalent to causing the static ring 6 to dynamically float under the action of the water pressure at both ends of the static ring 6, so that the leakage of the friction pair can be kept appropriate while meeting the cooling and lubrication requirements of the friction pair;

[0048] In addition, in order to prevent the axial floating amount of the stationary ring 6 from being too large, four springs 9 are additionally provided in this embodiment. The main function of the spring 9 is to damp the floating of the stationary ring 6, so it is not necessary for it to have a large thrust to act on the seal of the friction pair. Therefore, the spring force of the spring 9 can be designed to be smaller to increase 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 the spring 9 can be moved in the opposite direction of the suction direction of the impeller 2 (i.e. Figure 4 The spring 9 is removed from the guide hole 4 (from right to left in the middle), and the pump body 1 does not need to be removed during maintenance, thereby significantly reducing the maintenance workload.

[0049] Example 3

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

[0051] The impeller 2 is a semi-open impeller; the dynamic ring 7 is arranged on the suction port side of the blades of the impeller 2, and the dynamic ring 7 is directly processed on the blank of the impeller 2 to reduce the manufacturing cost.

[0052] Finally, in the above three embodiments, the medium (such as water) in the high-pressure water hole 104, high-pressure water pipe 3, water inlet hole 601, hidden water channel 10, water guide groove 602 and other components is only for the convenience of description, not for limitation of the medium. The same effect can be obtained by replacing it with other liquid media such as oil and alcohol.

[0053] The above is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A vane pump, characterized in that: It comprises a pump body, an impeller and a sealing device arranged between the pump body and the impeller, wherein the sealing device comprises a dynamic ring, a static ring, a positioning plate, a telescopic tube and a guide hole; the dynamic ring is mounted on the front cover plate of the impeller or on the suction port side of the blade; the guide hole is arranged on the suction side of the pump body and is coaxial with the impeller, and the static ring, the telescopic tube and the positioning plate are arranged in the guide hole in sequence from the inside to the outside; one end of the telescopic tube is fixed on the positioning plate, and the other end is fixed on the static ring, the static ring and the guide hole are clearance-fitted, the static ring can move along the axial direction of the guide hole and can contact the dynamic ring; the positioning plate is fixed on the pump body; the medium enters the impeller suction port from the radial inner side of the positioning plate, the telescopic tube and the static ring in sequence.

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, and the integral structure can be installed in the guide hole along the suction direction of the impeller.

3. The vane pump according to claim 1, characterized in that: The positioning plate is provided with a positioning flange at one end away from the impeller; a matching positioning stop is provided on the pump body 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 pipeline connecting the guide hole and the high pressure area / water outlet of the water 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 dynamic ring.

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

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

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

8. The vane pump according to claim 4, characterized in that: An inlet flange is arranged on the end portion outside the suction port of the pump body, and a high-pressure water hole for connecting to the high-pressure area / water outlet of the water pressure chamber is arranged on the inlet flange; the high-pressure water hole is arranged 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 tube.

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

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