阅读说明：本技术 一种泵用叶片可调节的无轴诱导轮 (Shaftless inducer with adjustable blades for pump ) 是由 朱荣生 王芮 付强 王秀礼 龙云 林彬 于 2020-06-22 设计创作，主要内容包括：本发明提供了一种泵用叶片可调节的无轴诱导轮,包括泵壳和叶轮,所述叶轮安装在泵壳内,所述叶轮的叶轮盖板延长段上均布若干诱导轮叶片,任一所述诱导轮叶片与叶轮盖板连接处设有定位装置,通过外力使诱导轮叶片克服定位装置的定位并驱动所述诱导轮叶片产生旋转,用于调节诱导轮叶片的角度；所述泵壳外部设有推力旋转装置,用于提供所述外力。本发明通过调节叶片安放角度,使得泵在不同工况条件下也能处在最优工况点运行；本发明适用于进口来流为低压的情况；本发明诱导轮采用无轮毂形式,把叶片安装在叶轮的盖板加长处,减轻了诱导轮的重量,提供更多的进口面积,从而提高泵的效率。(The invention provides a shaftless inducer with adjustable blades for a pump, which comprises a pump shell and an impeller, wherein the impeller is arranged in the pump shell, a plurality of inducer blades are uniformly distributed on an extension section of an impeller cover plate of the impeller, a positioning device is arranged at the joint of any inducer blade and the impeller cover plate, and the inducer blades overcome the positioning of the positioning device and are driven to rotate by external force so as to adjust the angles of the inducer blades; and a thrust rotating device is arranged outside the pump shell and used for providing the external force. According to the invention, the pump can operate at the optimal working condition point under different working conditions by adjusting the mounting angle of the blades; the invention is suitable for the condition that the incoming flow at the inlet is low pressure; the inducer adopts a hubless form, and the blades are arranged at the added part of the cover plate of the impeller, so that the weight of the inducer is reduced, more inlet areas are provided, and the efficiency of the pump is improved.)

1. The shaftless inducer with adjustable blades for the pump comprises a pump shell (6) and an impeller (1), wherein the impeller (1) is installed in the pump shell (6), and is characterized in that a plurality of inducer blades (5) are uniformly distributed on an extension section of an impeller cover plate (101) of the impeller (1), a positioning device is arranged at the joint of any inducer blade (5) and the impeller cover plate (101), and the inducer blade (5) overcomes the positioning of the positioning device through external force and drives the inducer blade (5) to rotate so as to adjust the angle of the inducer blade (5); and a thrust rotating device is arranged outside the pump shell (6) and is used for providing the external force.

2. The blade-adjustable shaftless inducer for the pump according to claim 1, wherein the positioning device comprises a connecting rod (12), a first gear (8) and a second gear (9, 9 '), the inducer blade (5) is provided with the connecting rod (12) at one end, the first gear (8) is mounted on the connecting rod (12), the impeller cover plate (101) is provided with a mounting hole, the second gear (9, 9 ') is fixedly mounted in the mounting hole, the connecting rod (12) passes through the mounting hole, and the first gear (8) is meshed with the second gear (9, 9 '); the connecting rod (12) is axially moved by the external force, the first gear (8) is separated from the second gear (9 and 9'), and the connecting rod (12) is rotated by the external force to adjust the angle of the inducer blade (5).

3. The adjustable blade shaftless inducer for pumps according to claim 2, wherein said positioning means further comprises a first returning means provided on said connecting rod (12) for engaging said first gear (8) with said second gear (9, 9') after said external force disappears.

4. The blade-adjustable shaftless inducer for pumps according to claim 2, wherein the first and second gears (8, 9') are a pair of external gears or a pair of internal gears.

5. The adjustable blade shaftless inducer for the pump according to claim 2, wherein the thrust rotation device comprises a control rod (15) and a boss (14), a communication hole is formed on the pump shell (6), the boss (14) is formed at one end of the control rod (15), a groove (10) matched with the boss (14) is formed on the connecting rod (12), the control rod (15) passes through the communication hole and is used for enabling the boss (14) to be jointed with or separated from the groove (10) through the axial movement of the control rod (15); the angle of the inducer blade (5) is adjusted by rotating the control rod (15).

6. The adjustable blade shaftless inducer for pumps according to claim 5, wherein said thrust rotation means further comprises a sealing member (17) and a second return means, said through hole and control rod (15) being provided with a sealing member (17); and a second resetting device is arranged on the control rod (15) and is used for separating the boss (14) from the groove (10).

7. The adjustable vane shaftless inducer for pumps according to claim 5, wherein the boss (14) is in the shape of a raised straight line or polygon.

Technical Field

The invention relates to the field of fluid machinery, in particular to a shaftless inducer with adjustable blades for a pump.

Background

When the water pump works, if the pressure at a certain point in the water pump is reduced to the working temperature, the water begins to vaporize under the saturated steam pressure of the water, and the vaporization phenomenon is intensified along with the reduction of the pressure in the pump shell and the increase of the water temperature. Cavitation can damage the impeller and the pump shell, and can generate spots and cracks on the surface of the impeller and the pump shell after a certain time, and can generate noise to vibrate the pump body. The long-time operation under the cavitation state can greatly reduce the service life of the pump. There are many methods for preventing or reducing the cavitation, such as adding an inducer at the inlet, selecting an appropriate pump mounting height, increasing the diameter of the impeller inlet, and the like. The inducer added at the inlet is one of the most effective methods for improving the cavitation performance of the centrifugal pump at present and is widely applied.

The inducer belongs to an axial flow impeller, has the geometric characteristics and the cavitation characteristics of the axial flow impeller, is used for improving the cavitation performance of the centrifugal pump, and can work under a certain degree of cavitation state. It operates without excessive performance loss due to cavitation by increasing the pressure at the inlet of the main impeller of the pump. The pump has the following functions after being provided with an ideal inducer: the pump can reduce the NPSHR (pump cavitation allowance) by at least 50%, improve the capacity of the pump for conveying viscous materials, eliminate noise in vacuum application and improve the capacity of the pump for conveying gas phase, and in addition, in the application of the NPSHA (device cavitation allowance) deficiency and treatment of gas-containing and viscous materials, the service life of flow passage components such as an impeller, a pump body, a cover plate and the like can be prolonged.

The Chinese patent discloses that the blade angle of an impeller of an axial flow pump in work is adjusted by using the meshing rotation of a helical gear, so that the impeller blade rotates within a certain angle range, and the condition that the blades collide with each other cannot occur. This patent is that the wheel hub internally mounted adjusting device adjusts the impeller blade, inconvenient operation and maintenance. The Chinese patent discloses that the inducer is set to be in a variable-pitch structure, the blade inlet angle of the spiral blade is smaller than the blade outlet angle, and the thickness of the spiral blade gradually becomes thicker from the blade tip to the blade root, so that better cavitation performance is obtained, the inlet pressure of the impeller is improved, and the influence of cavitation on the impeller is effectively reduced. The patent only improves the blade structure of the inducer, and does not relate to an inducer blade adjustable device.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the shaftless inducer with adjustable blades for the pump, so that the blades of the inducer can be adjusted, and the pump can also operate at the optimal working condition point under different working conditions by adjusting the installation angle of the blades; the invention is suitable for the condition that the incoming flow at the inlet is low pressure; the inducer adopts a hubless form, and the blades are arranged at the added part of the cover plate of the impeller, so that the weight of the inducer is reduced, more inlet areas are provided, and the efficiency of the pump is improved.

The present invention achieves the above-described object by the following technical means.

A shaftless inducer with adjustable blades for a pump comprises a pump shell and an impeller, wherein the impeller is installed in the pump shell, a plurality of inducer blades are uniformly distributed on an extension section of an impeller cover plate of the impeller, a positioning device is arranged at the joint of any inducer blade and the impeller cover plate, and the inducer blades overcome the positioning of the positioning device and drive the inducer blades to rotate through external force so as to adjust the angles of the inducer blades; and a thrust rotating device is arranged outside the pump shell and used for providing the external force.

Furthermore, the positioning device comprises a connecting rod, a first gear and a second gear, one end of the inducer blade is provided with the connecting rod, the first gear is mounted on the connecting rod, the impeller cover plate is provided with a mounting hole, the second gear is fixedly mounted in the mounting hole, the connecting rod penetrates through the mounting hole, and the first gear is meshed with the second gear; the connecting rod is axially moved through the external force, so that the first gear is separated from the second gear, and then the connecting rod is rotated through the external force, so that the angle of the inducer blade is adjusted.

Furthermore, the positioning device further comprises a first reset device, and the connecting rod is provided with the first reset device and used for enabling the first gear to be meshed with the second gear after the external force disappears.

Further, the first gear and the second gear are a pair of external gears or a pair of internal gears.

Further, the thrust rotating device comprises a control rod and a boss, a communicating hole is formed in the pump shell, the boss is arranged at one end of the control rod, a groove matched with the boss is formed in the connecting rod, the control rod penetrates through the communicating hole and is used for enabling the boss to be connected with or separated from the groove through axial movement of the control rod; the angle of the inducer blade is adjusted by rotating the control rod.

Furthermore, the thrust rotating device also comprises a sealing element and a second resetting device, and the through hole and the control rod are provided with the sealing element; and a second resetting device is arranged on the control rod and used for separating the boss from the groove.

Further, the boss is a raised linear shape or a polygonal shape.

The invention has the beneficial effects that:

1. the adjustable shaftless inducer for the pump blade has stronger anti-cavitation performance, and can effectively improve the cavitation performance of the pump.

2. The adjustable shaftless inducer with the blades for the pump can be suitable for different working conditions by adjusting the blades of the inducer, and the optimal working condition point is found under different working conditions, so that the pump keeps high efficiency in a larger working condition change range.

3. The adjustable shaftless inducer for the blades of the pump, disclosed by the invention, is a shaftless and hubless inducer, is more convenient to manufacture and install, reduces the manufacturing cost, is convenient to maintain and nurse, and meanwhile, the weight of the inducer is reduced, the inlet area is increased, and the working efficiency of the pump is improved.

4. The adjustable shaftless inducer for the blades for the pump, disclosed by the invention, has the advantages that the blades only rotate within a certain angle range, the blades cannot collide as long as the rotating angle is properly set, the adjusting mechanism is simple, the operation is convenient, the realization is easy, and the adjustment of the blades of the inducer can be completed under the condition of ensuring no collision.

Drawings

Fig. 1 is a structural diagram of a blade-adjustable shaftless inducer for a pump according to the present invention.

Fig. 2 is a sectional view a-a of fig. 1.

Fig. 3a and 3b are diagrams of the adjustment process of embodiment 1 of the present invention.

Fig. 4a and 4b are diagrams of the adjustment process of embodiment 2 of the present invention.

FIG. 5 is a sectional view taken along line B-B in example 1.

FIG. 6 is a sectional view taken along line B-B in example 2.

In the figure:

1-an impeller; 2-locking the nut; 3-a sealing assembly; 4-a pump shaft; 5-inducer blade; 6-pump casing; 101-impeller cover plate; 8-a first gear; 9-a gear ring; 9' -an outer gear; 10-a groove; 11-connecting rod spring; 12-a connecting rod; a 13-bond; 14-a boss; 15-a control lever; 16-a lever spring; 17-a seal; 18-lever cover plate; 19-a screw; 20-control lever rotating handle.

Detailed Description

The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.

As shown in fig. 1 and 2, the non-shaft inducer with adjustable blades for a pump mainly comprises an impeller 1, a lock nut 2, a sealing assembly 3, a pump shaft 4, an inducer blade 5, a pump casing 6, an impeller cover plate 101, a first gear 8, a second gear 9, a groove 10, a connecting rod spring 11, a connecting rod 12, a key 13, a boss 14, a control rod 15, a control rod spring 16, a sealing member 17, a control rod cover plate 18, a screw 19 and a control rod rotating handle 20.

The impeller 1 is installed in a pump shell 6, the impeller 1 is connected with a pump shaft 4 and fixed through a locking nut 2, sealing processing is carried out through a sealing assembly 3, a plurality of inducer blades 5 are uniformly distributed on an extension section of an impeller cover plate 101 of the impeller 1, a positioning device is arranged at the joint of any inducer blade 5 and the impeller cover plate 101, and the inducer blades 5 overcome the positioning of the positioning device through external force and drive the inducer blades 5 to rotate so as to adjust the angles of the inducer blades 5; and a thrust rotating device is arranged outside the pump shell 6 and used for providing the external force.

The positioning device comprises a connecting rod 12, a first gear 8 and a second gear, wherein one end of the inducer blade 5 is provided with the connecting rod 12, the first gear 8 is installed on the connecting rod 12, the impeller cover plate 101 is provided with an installation hole, the second gear is fixedly installed in the installation hole, the connecting rod 12 penetrates through the installation hole, and the first gear 8 is meshed with the second gear; the blade connecting rod 12 is provided with a stepped shaft shoulder, and two ends of the connecting rod spring 11 are respectively connected and fixed with the shaft shoulder and the inner wall of the cover plate. The connecting rod 12 is axially moved by the external force to separate the first gear 8 from the second gear, and then the connecting rod 12 is rotated by the external force to adjust the angle of the inducer blade 5.

The thrust rotating device comprises a control rod 15 and a boss 14, a communicating hole is formed in the pump shell 6, the boss 14 is arranged at one end of the control rod 15, a groove 10 matched with the boss 14 is formed in the connecting rod 12, the control rod 15 penetrates through the communicating hole and is used for enabling the boss 14 to be connected with or separated from the groove 10 through axial movement of the control rod 15; by rotating the control lever 15, the angle of the inducer blade 5 is adjusted.