AU2012101164A4

AU2012101164A4 - Helical flow constant pressure pump

Info

Publication number: AU2012101164A4
Application number: AU2012101164A
Authority: AU
Inventors: Shihuang Li
Original assignee: SUZHOU SCS FLUID TECHNOLOGY CO Ltd
Current assignee: SUZHOU SCS FLUID TECHNOLOGY Co Ltd
Priority date: 2012-07-31
Filing date: 2012-07-31
Publication date: 2012-08-30
Anticipated expiration: 2020-07-31

Abstract

The present invention relates to centrifugal pumps, and specifically discloses a helical flow constant pressure pump. The helical flow constant pressure pump includes a pump casing and an impeller. An inner wall of the pump casing is circular arc shaped. The 5 impeller includes a back cover plate having a wheel hub portion and a plurality of front vanes that are located on a front side of the back cover plate and are integrally formed with the back cover plate. Each front vane is bent at a portion near a circular edge of the back cover plate in a counterclockwise direction, and is tilted in a clockwise direction, so as to form a bent and tilted portion that forms a certain angle with a front surface of the back 10 cover plate. The helical flow constant pressure pump of the present invention enables liquid in a pump chamber to flow in a longitudinal direction toward a pump front cover, and meanwhile, flow rotationally, thereby forming a helical flow in the pump. The liquid flow is enabled to enter a space between the front vanes of the impeller for multiple times, and a pressure of the liquid flow is boosted. A pump outlet pressure is higher and more stable 15 compared with that of a vortex flow constant pressure pump in the prior art. FIG. 2 FIG. 3 FIG. 6 FIG. 7

Description

Regulation 3.2 AUSTRALIA Patents Act 1990 INNOVATION PATENT SPECIFICATION (ORIGINAL) Name of Applicant: Suzhou SCS Fluid Technology Co., Ltd of 215137 No. 9. Jin Yu Road, TaiPing Industrial Park, Xiang Cheng Area, Suzhou City, Jiangsu Province, P.R. China Actual Inventor: LI Shihuang Address for Service: DAVIES COLLISON CAVE, Patent Attorneys, 1 Nicholson Street, Melbourne 3000, Victoria, Australia Innovation Patent specification for the invention entitled: "Helical flow constant pressure pump" The following statement is a full description of this invention, including the best method of performing it known to us: C-\NRI'OR'lI.\DCC\EJI.\45040 1_1 DOC - 31/7/12 HELICAL FLOW CONSTANT PRESSURE PUMP BACKGROUND OF THE INVENTION Field of Invention The present invention relates to centrifugal pumps, and specifically relates to a helical 5 flow constant pressure pump. Related Art CN2764967Y discloses a vortex flow constant pressure pump. The vortex flow constant pressure pump includes a pump body, a pump front cover, a pump back cover, a pump spindle, an impeller, and an electric motor. The pump back cover is fixedly installed 10 on a front side of the pump body, and the pump front cover is fixedly mounted on a front side of the pump back cover. The pump front cover and the pump back cover together constitute a pump casing that forms a pump chamber. The pump spindle is rotatably supported in the pump body by a bearing. A front portion of the pump spindle is located in filler in a stuffing box mounted on the pump back cover, a front end of the pump spindle 15 extends into the pump chamber, and the impeller is fixedly mounted on the front end of the pump spindle. The pump front cover has a horizontal liquid inlet on a front side, and has a perpendicular liquid outlet on a right side. The impeller consists of a back cover plate having a wheel hub and a plurality of front vanes and a plurality of back vanes, which are located on a front side and a back side of the back cover plate and are integrally formed 20 with the back cover plate. The front vanes are higher than the back vanes. As shown in FIG. 6 and FIG. 7, a front vane 10 is tilted from a point A, which is a certain distance away from the center 0 of a circle of the back cover plate 20, in a clockwise direction while being perpendicular to the back cover plate 20 and being in the shape of a straight line, and forms a certain angle with a straight line linking the center 0 of the circle and the starting point A 25 of the front vane. The front vane 10 is bent at a point B near a circular edge of the back cover plate 20 in a counterclockwise direction, and is tilted in a counterclockwise direction, thereby forming a certain angle with a front surface of the back cover plate 20. An outer edge 12 of the front vane 10 is tilted inward from a point C of a rear root portion I I of the front vane 10 to a point D of a front free edge 13, which has a line drawn parallel thereto, of the front vane 10. An inner wall of the pump front cover is circular arc shaped. In this 5 vortex flow constant pressure pump, since the front vane 10 is bent at a portion close to the circular edge of the back cover plate 20 in a counterclockwise direction, and is tilted in a counterclockwise direction, liquid in the pump chamber may produce a vortex flow, so that a pump outlet pressure may be increased to a certain extent, and the pump outlet pressure may basically maintain stable. However, since the front vane 10 is bent at the portion close 10 to the circular edge of the back cover plate 20 in a counterclockwise direction, and is tilted in a counterclockwise direction, as shown in FIG. 6, an angle a formed by a center line of the rear root portion I I of the portion of the front vane 10 and a center line of a section AB of the front vane 10 is smaller than an angle b formed by a center line of the front free edge portion 13, which has a line drawn parallel thereto, of the portion of the front vane 10 and 15 the center line of the section AB of the front vane 10, so that an absolute velocity of liquid leaving the front free edge portion 13 is greater than an absolute velocity of liquid leaving the rear root portion 11. In this way, the liquid in the pump chamber can not flow in a longitudinal direction toward the pump front cover, and the pressure can not be further increased. 20 SUMMARY OF THE INVENTION In order to solve the problem that a pressure of a vortex flow constant pressure pump in the prior art is low, the present invention provides a helical flow constant pressure pump. The helical flow constant pressure pump of the present invention includes a pump casing and an impeller. An inner wall of the pump casing is circular arc shaped. The 25 impeller includes a back cover plate having a wheel hub portion and a plurality of front vanes, which are located on a front side of the back cover plate and are integrally formed with the back cover plate. In the helical flow constant pressure pump, each front vane is 2 bent at a portion near a circular edge of the back cover plate in a counterclockwise direction, and is tilted in a clockwise direction, thereby forming a bent and tilted portion that forms a certain angle with a front surface of the back cover plate. In the helical flow constant pressure pump of the present invention, since the front vane 5 is bent at the portion near the circular edge of the back cover plate in a counterclockwise direction, and is tilted in a clockwise direction, the bent and tilted portion that forms a certain angle with the front surface of the back cover plate is formed, which enables liquid in a pump chamber to flow in a longitudinal direction toward a pump front cover, and meanwhile, flow rotationally, thereby forming a helical flow in the pump. The liquid flow is 10 enabled to enter a space between the front vanes of the impeller for multiple times, and a pressure of the liquid flow is boosted. A pump outlet pressure is higher and more stable compared with that of the vortex flow constant pressure pump in the prior art. The helical flow constant pressure pump of the present invention also includes and has the following technical features. 15 An outer edge of the bent and tilted portion is tilted inward by 3' to 10' from a rear root portion to a front free edge. The outer edge of the bent and tilted portion is tilted inward by 6' from the rear root portion to the front free edge. An inlet angle of the front vane is from 300 to 60'. 20 The inlet angle of the front vane is 45'. An outlet angle of the front free edge of the bent and tilted portion is from 90' to 130*. The outlet angle of the front free edge of the bent and tilted portion is 100'. An outlet angle of the rear root portion of the bent and tilted portion is from 1100 to 1400. 3 The outlet angle of the rear root portion of the bent and tilted portion is 1300. The inner wall of the circular arc shaped pump casing includes a front circular arc portion of a radius RI, a middle circular arc portion of a radius R2, and a back oblique straight line segment portion, which is tilted toward a center line of the pump casing from 5 the front to the back. The front circular arc portion of the radius RI, the middle circular arc portion of the radius R2 and the back oblique straight line segment portion, which is tilted toward the center line of the pump casing from the front to the back, rotate about the center line of the pump casing for one revolution to form the inner wall of the pump casing, and the radius R I is larger than the radius R2. 10 BRIEF DESCRIPTION OF THE DRAWINGS A helical flow constant pressure pump of the present invention is further illustrated in the following with reference to the accompanying drawings and embodiments. FIG. I is a schematic diagram of a longitudinal section of a helical flow constant pressure pump of the present invention; I5 FIG. 2 is a schematic front view diagram of a back cover plate of an impeller of a helical flow constant pressure pump of the present invention and a front vane on a front surface of the back cover plate; FIG. 3 is a schematic diagram.of a longitudinal section of a back cover plate of an impeller of a helical flow constant pressure pump and a front vane on a front surface of the 20 back cover plate and a back vane on a back surface of the back cover plate shown in FIG. 2; FIG. 4 is a schematic diagram of a longitudinal section of a pump casing of a helical flow constant pressure pump of the present invention; FIG. 5 is a schematic diagram of a back end surface of the pump casing shown in FIG. 4; 4 FIG. 6 is a schematic front view diagram of a back cover plate of an impeller of a vortex flow constant pressure pump in the prior art and a front vane on a front surface of the back cover plate; and FIG. 7 is a schematic diagram of a longitudinal section of the back cover plate of the 5 impeller of the helical flow constant pressure pump and a front vane on a front surface of the back cover plate and a back vane on a back surface of the back cover plate shown in FIG. 6. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a helical flow constant pressure pump of the present invention 10 includes a pump body 100, a pump casing 200, a pump spindle 300, an impeller 400, and an electric motor 500. The pump casing 200 is fixedly mounted on a front side of the pump body 100. The pump casing 200 and the pump body 100 together form a pump chamber 600. The electric motor 500 is fixedly mounted on a back side of the pump body 100. A spindle of the 15 electric motor 500 is used as the pump spindle 300. A front end of the pump spindle 300 extends into the pump chamber 600, and the impeller 400 is fixedly mounted on the front end of the pump spindle 300. The pump body 100 has a central sealed cavity 110. The central sealed cavity 1 10 has a set of publicly known end face seals or mechanical seals 120 mounted therein. The pump casing 200 has a horizontal liquid inlet 210 on a front side and 20 a perpendicular liquid outlet 220 on a right side. The impeller 400 includes a back cover plate 460 having a wheel hub portion 410 and a plurality of front vanes 450 and a plurality of back vanes 480, which are located on a front side and a back side of the back cover plate 460 and are integrally formed with the back cover plate. The front vanes 450 are higher than the back vanes 480. 25 A shape of the front vane 450 of the impeller 400 is shown in FIG. 2 and FIG. 3. An HI section of the front vane 450 is the same as an AB section of a front vane 10 of an impeller 5 of a vortex flow constant pressure pump in the prior art shown in FIG. 6 and FIG. 7. However, the HI section of the front vane 450 is bent at a point I near a circular edge of the back cover plate 460 in a counterclockwise direction, and is tilted in a clockwise direction, thereby forming a bent and tilted portion that forms a certain angle with a front surface of 5 the back cover plate 460. An outer edge 452 of the bent and tilted portion is tilted inward from a point J of a rear root portion 451 to a point K of a front free edge 453, which has a line drawn parallel thereto, at a tilt angle of 30 to 100, preferably 6'. Since the front vane 450 is bent at a portion close to the circular edge of the back cover plate 460 in a counterclockwise direction, and is tilted in a clockwise direction, the bent and tilted portion 10 that forms a certain angle with the front surface of the back cover plate 460 is formed. As shown in FIG. 2, an angle d formed by a center line of the rear root portion 45 1 of the bent and tilted portion and a center line of the section HI of the front vane 450 is larger than an angle c formed by a center line of the front free edge portion 453, which has a line drawn parallel thereto, of the bent and tilted portion and the center line of the section HI of the 15 front vane 450, so that an absolute velocity of liquid leaving the front free edge portion 453 is smaller than an absolute velocity of liquid leaving the rear root portion 451. In this way, the liquid in the pump chamber is enabled to flow in a longitudinal direction toward a pump front cover, and meanwhile, flow rotationally, thereby forming a helical flow in the pump. The liquid flow enters a space between a plurality of front vanes 450 in a counterclockwise 20 direction of this front vane 450 for multiple times, and a pressure of the liquid flow is continually boosted and maintains stable when reaching a highest pressure. An inlet angle g of the front vane 450 is from 30 to 600, and preferably 45'. An outlet angle p of the free edge portion 453, which has a line drawn parallel thereto, of the bent and tilted portion is from 90' to 1300, and preferably 100*. An outlet angle q of the rear root portion 451 of the 25 bent and tilted portion is from 1100 to 140', and preferably 1300. In this way, an outlet pressure of the pump may be higher and more stable. Referring to FIG. 4 and FIG. 5, in order to conduct the helical flow, which is formed in the pump by the front vane 450 of the impeller 400, to enter the space between the plurality of front vanes 450 of the impeller 400 for multiple times, and further improve the pump 6 outlet pressure, in the present invention, a single-circular arc shaped inner wall of a front cover of the vortex flow constant pressure pump in the prior art is changed into a multiple-circular arc shaped inner wall. As shown in FIG. 4, an inner wall of the pump casing 200 of the helical flow constant pressure pump of the present invention includes a 5 front circular arc portion 260 of a radius RI, a middle circular arc portion 270 of a radius R2, and a back oblique straight line segment portion 280, which is titled toward a center line of the pump casing 200 from the front to the back. The front circular arc portion 260 of the radius RI, the middle circular arc portion 270 of the radius R2, and the back oblique straight line segment portion 280, which is titled toward the center line of the pump casing 10 200 from the front to the back, rotate about the center line of the pump casing 200 for one revolution to form the inner wall of the pump casing 200. The radius RI is larger than the radius R2. In the helical flow constant pressure pump of the present invention, an outlet centrifugal force of the rear root portion 451 of the bent and tilted portion of the front vane 15 450 of the impeller 400 is greater than an outlet centrifugal force of the front free edge of the bent and tilted portion of the front vane 450, and a liquid flow pressure of the rear root portion of the bent and tilted portion is correspondingly higher than a liquid flow pressure of the front free edge of the bent and tilted portion. Therefore, a liquid flow direction is pointed from the rear root portion of the bent and tilted portion to the front free edge of the 20 bent and tilted portion. A longitudinal fluid motion is produced, and meanwhile, a vortex fluid motion is produced with the impeller 400, thereby forming a helical flow. The helical flow once again enters the space between the plurality of front vanes 450 of the impeller 400, and a pressure of the helical flow is once again boosted, an effect of which is similar to that of a multistage centrifugal pump, and a high lift and a constant pressure are obtained. In 25 this process, a volute circular arc of the pump casing 200 plays a good conducting role. Besides, a spacing between the front vane 450 and the inner wall of the pump casing 200 is large, so that when liquid containing a large quantity of solid impurities is being pumped, the front vane 450 is not easy to wear. 7

Claims

1. A helical flow constant pressure pump, comprising a pump casing and an impeller, an inner wall of the pump casing being circular arc shaped, and the impeller comprising a 5 back cover plate having a wheel hub portion and a plurality of front vanes, which are located on a front side of the back cover plate and are integrally formed with the back cover plate, wherein each front vane is bent at a portion near a circular edge of the back cover plate in a counterclockwise direction, and is tilted in a clockwise direction, so as to form a bent and tilted portion that forms a certain angle with a front surface of the back cover 10 plate.

2. The helical flow constant pressure pump according to claim 1, wherein an outer edge of the bent and tilted portion of the vane is tilted inward from a rear root portion to a front free edge of the vane by 30 to 10' relative to an axis of the impeller in a radial direction. 15

3. The helical flow constant pressure pump according to claim 2, wherein the outer edge of the bent and tilted portion of the vane is tilted inward from the rear root portion to the front free edge of the vane by 60 relative to the axis of the impeller in the radial direction.

4. The helical flow constant pressure pump according to claim 1, wherein an inlet 20 angle of the front vane is from 30 to 600.

5. The helical flow constant pressure pump according to claim 4, wherein the inlet angle of the front vane is 45*.

6. The helical flow constant pressure pump according to claim 1, wherein an outlet angle of a front free edge of the bent and tilted portion is from 90' to 130'. 8

7. The helical flow constant pressure pump according to claim 6, wherein the outlet angle of the front free edge of the bent and tilted portion is 1000.

8. The helical flow constant pressure pump according to claim 1, wherein an outlet angle of a rear root portion of the bent and tilted portion is from I 100 to 1400. 5

9. The helical flow constant pressure pump according to claim 8, wherein the outlet angle of the rear root portion of the bent and tilted portion is 1300.

10. The helical flow constant pressure pump according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, wherein the inner wall of the circular arc shaped pump casing comprises a front circular arc portion of a radius RI, a middle circular arc portion of a radius R2, and a back oblique 10 straight line segment portion, which is tilted toward a center line of the pump casing from the front to the back, and the front circular arc portion of the radius RI, the middle circular arc portion of the radius R2 and the back oblique straight line segment portion, which is tilted toward the center line of the pump casing from the front to the back, rotate about the center line of the pump casing for one revolution to form the inner wall of the pump casing, 15 and the radius RI is larger than the radius R2. 9