HIGH-PRESSURE WATER PUMP LUBRICATED BY WATER OR AQUEOUS SOLUTION

Abstract

A high-pressure water pump lubricated by water or aqueous solution is provided, relating to the technical field of high-pressure plunger pumps. The high-pressure water pump includes a driving mechanism, at least one plunger, a plunger cavity, and a shell. The driving mechanism includes an eccentric wheel shaft and thrust rings. The eccentric wheel shaft includes a main shaft and multiple eccentric wheels arranged on the main shaft. The eccentric wheels are integral eccentric wheels and combined eccentric wheels, respectively. Compared with an original combined eccentric wheel structure mode, the eccentric wheel shaft provided by the present disclosure obviously improve anti-deflection characteristics of the main shaft, and thereby prolongs the service life of the high-pressure water pump. Moreover, the thrust ring structure can be conveniently installed, the structure is simple and compact, and the weight is light.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims the benefit and priority of Chinese Patent Application No. 2023108155724 filed with the China National Intellectual Property Administration on Jul. 4, 2023, the disclosure of which is incorporated by reference herein in its entirety as part of the present application.

TECHNICAL FIELD

The present disclosure relates to the technical field of high-pressure water pumps lubricated by water or aqueous solution.

BACKGROUND

The high-pressure water pump is used for producing high-pressure water. As a core component, the high-pressure water pump is widely applied to the fields of high-pressure cleaning, fine mist fire extinguishing, seawater desalination and other fields.

The high-pressure water pumps widely used at present are reciprocating pumps and water-lubricated axial plunger pumps.

The reciprocating pump has a long history, is widely used in the production of high-pressure water, and is mainly composed of a crankshaft, connecting rods, crossheads, plungers and other components. Lubricating oil is used for lubricating the power end, and a sealing ring is needed for sealing pressurized water and isolating water and lubricating oil. The main problems of this type of pump are that: the lubricating oil needs to be replaced regularly, and the lubricating oil will pollute the environment, and the sealing ring has short service life and is troublesome to replace.

In the 1990s, a commercial water-lubricated axial plunger pump is successfully provided by taking Danfoss as a representative. Compared with the reciprocating pump, the water-lubricated axial plunger pump has the advantages of environmental protection, high energy efficiency and the like., but has the disadvantages of low output pressure, poor water pollution resistance, complex structure, and high price.

For newly developed water-lubricated piston pumps an eccentric wheel shaft is selected as the driving mechanism, and the eccentric wheel is sleeved with a thrust ring structure. When the eccentric wheel shaft rotates, the thrust ring structure pushes the plunger to move to achieve the pressurized output of water or aqueous solution.

When three or more eccentric wheels are used for the eccentric wheel shaft, as it is preferable that the outer diameters of each eccentric wheels are the same and there is a phase difference between the eccentric wheels in the rotation direction, the annular thrust ring cannot pass through the eccentric wheels on both sides to be sleeved outside the eccentric wheel in the middle position.

In the early stage, the traditional combined eccentric wheel shaft structure was adopted to solve this assembly problem. The specific implementation method is as follows: the eccentric wheel and the shaft body are separately prepared, and after the eccentric wheel at the central position is in interference press-fit with the shaft body, the thrust ring corresponding to the eccentric wheel at the central position is assembled, and then the eccentric wheel and the thrust ring close to the outer side are further assembled.

In the plunger pump lubricated by water, the movement of the plunger can pressurize the water, and conversely, the pressurized water exerts a reaction force on the plunger in the direction of the eccentric wheel shaft. The plunger transmits the force to the thrust ring, and the thrust ring continues to apply the force to the eccentric wheel shaft. Because the pressure of water can be as high as tens of MPa, this reaction force may exceed 10 thousand Newton. Because the eccentric wheel shaft adopts the bearing support structure at both ends, the span between the bearings can reach 200 mm and more, and the eccentric wheel shaft will produce obvious flexural deformation under the high reaction load at the middle part of the shaft. For the rolling bearings, there are generally strict control requirements for the flexural deformation of the shaft (e.g., if cylindrical roller bearings are used, the flexural deformation of the shaft at the bearing installation site cannot exceed 4 arcmin). If the flexural deformation of the shaft cannot be well controlled, the service life of the bearing will be significantly reduced and the bearing noise will be increased. In addition, the flexural deformation of the shaft will also increase a bending moment of the plunger and increase the wear and leakage of the plunger and plunger cavity.

Although the traditional combined eccentric wheel is simple to manufacture, due to the discontinuous materials of eccentric wheel and spindle, the problem of weak bending stiffness of the eccentric wheel shaft is revealed for higher power pump application requirements. In order to meet the demand of stiffness, the traditional measures to improve stiffness, such as increasing the diameter of the shaft, will significantly increase the size and weight of the eccentric wheel shaft, which destroys the economy and convenience of the pump.

Based on this, a novel high-stiffness shaft scheme is urgently needed to solve the above problems faced by the realization of water pump.

SUMMARY

An objective of the present disclosure is to provide a high-pressure water pump lubricated by water or aqueous solution, so as to solve the problems existing in the prior art, remarkably improve the anti-deflection characteristics of the main shaft, and achieve the convenient installation of the thrust ring structure, with a simple and compact structure and light weight.

To achieve the objective above, the present disclosure provides the following solutions:

A high-pressure water pump lubricated by water or aqueous solution provided by the present disclosure includes a driving mechanism, at least one plunger, a plunger cavity, and a shell. The driving mechanism includes an eccentric wheel shaft and thrust rings. The eccentric wheel shaft includes a main shaft, and a plurality of eccentric wheels arranged on the main shaft. Each thrust ring is sleeved outside one of the eccentric wheels. Said each thrust ring and said one of eccentric wheels can rotate with respect to each other. Both ends of the main shafts are bearing supporting sections. The eccentric wheels and thrust rings are located in the shell, and a space in the shell where the eccentric wheels and thrust rings are located is also used to be filled with water or aqueous solution. When the eccentric wheels shaft rotate, the plunger can be driven by the thrust rings to move in the plunger cavity to pressurize the water or aqueous solution.

The eccentric wheels are integral eccentric wheels or combined eccentric wheels. A material between the integral eccentric wheels and the main shaft is continuous. Each of the combined eccentric wheels includes a reinforcing mandrel and an eccentric wheel sleeve. A profile curve of the reinforcing mandrel on a projection plane perpendicular to the central line of the main shaft is non-circular, the eccentric wheel sleeve is sleeved outside the reinforcing mandrel, the reinforcing mandrel can drive the eccentric wheel sleeve to rotate synchronously, and the material between the reinforcing mandrel and the main shaft is continuous.

When there are three eccentric wheels, at least one eccentric wheel located at the central position is the integral eccentric wheel, and at least one eccentric wheel located at the outermost side is the combined eccentric wheel.

When there are four eccentric wheels, at least two eccentric wheels located at the central position are the integral eccentric wheels, and at least one eccentric wheel located at the outermost side is the combined eccentric wheel.

Preferably, the profile curve of the reinforcing mandrel on the projection plane perpendicular to the central line of the main shaft surrounds the periphery of a profile curve of the bearing supporting section on the projection plane perpendicular to the central line of the main shaft.

Preferably the profile curve of the reinforcing mandrel on the projection plane perpendicular to the central line of the main shaft is surrounded by a profile curve of the adjacent integral eccentric wheel on the projection plane perpendicular to the central line of the main shaft.

Preferably, when the eccentric wheel shaft rotates, the thrust rings can roll on a surface in contact with the plunger and push the plunger to move in the plunger cavity, so as to pressurize the water or aqueous solution.

Compared with the prior art, the present disclosure has the following technical effects:

For the flexural deformation problem faced by the eccentric wheel shaft of the plunger pump lubricated by water, the eccentric wheel shaft provided by the present disclosure obviously improves the anti-deflection characteristics of the main shaft in comparison with the original combined eccentric wheel structure, and thereby prolongs the service life of the high-pressure water pump. Moreover, the thrust ring structure can be conveniently installed, the structure is simple and compact, and the weight is light.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the present disclosure or in the prior art more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments. Apparently, the accompanying drawings in the following description show merely some embodiments of the present disclosure, and those of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

FIG. 1 is a sectional view of a high-pressure water pump lubricated by water or aqueous solution according to the present disclosure;

FIG. 2 is a sectional view of a driving mechanism according to the present disclosure;

FIG. 3 is an exploded view of a driving mechanism according to the present disclosure;

FIG. 4 is an axonometric diagram (Embodiment 1) of an eccentric wheel shaft according to the present disclosure;

FIG. 5 is a front view of an integral eccentric wheel and a main shaft according to the present disclosure;

FIG. 6 is a side view of FIG. 5;

FIG. 7 is a schematic diagram of an eccentric wheel sleeve according to the present disclosure;

FIG. 8 is an axonometric diagram (Embodiment 2) of an eccentric wheel shaft according to the present disclosure.

In the drawings: 100—high-pressure water pump lubricated by water or aqueous solution; 1—driving mechanism; 2—rebound structure; 3—plunger; 4—plunger cavity; 5—shell; 6—eccentric wheel shaft; 7—thrust ring; 8—main shaft; 9—eccentric wheel; 10—bearing supporting section; 11—bearing; 12—friction layer; 13—integral eccentric wheel; 14—combined eccentric wheel; 15—reinforcing mandrel; 16—eccentric wheel sleeve; 17—profile curve of reinforcing mandrel on projection plane perpendicular to central line of main shaft; 18—profile curve of bearing supporting section on projection plane perpendicular to central line of main shaft; 19—profile curve of integral eccentric wheel on projection plane perpendicular to central line of main shaft.

DETAILED DESCRIPTION

The following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are merely a part rather than all of the embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

An objective of the present disclosure is to provide a high-pressure water pump lubricated by water or aqueous solution. For the existing problem that the eccentric wheel shaft is obvious in flexural deformation, an eccentric wheel shaft structure simultaneously provided with the integral eccentric wheel and the combined eccentric wheel is provided, which remarkably improves the anti-deflection characteristics of the main shaft, and can achieve the convenient installation of the thrust ring structure, with a simple and compact structure and light weight.

To make the objectives, features and advantages of the present disclosure more apparently and understandably, the following further describes the present disclosure in detail with reference to the accompanying drawings and the specific embodiments.

Embodiment 1

As shown in FIG. 1 through FIG. 7, a high-pressure water pump 100 lubricated by water or aqueous solution is provided according to this embodiment, including a driving mechanism 1, a rebound structure 2, at least one plunger 3, a plunger cavity 4, and a shell 5. As shown in FIG. 2, the driving mechanism 1 includes an eccentric wheel shaft 6 and thrust rings 7. As shown in FIG. 4, the eccentric wheel shaft 6 includes a main shaft 8 and multiple eccentric wheels 9 arranged on the main shaft 8. Portions at both ends, extending out of the eccentric wheels, of the main shaft 8 are bearing supporting sections 10. The bearing supporting sections 10 are used for installing bearings 11, so as to achieve a rotatable connection of the eccentric wheel shaft 6 and the shell 5. The bearing supporting sections 10 are also used for the providing of contact sealing elements (not shown), so as to seal the water or aqueous solution in the shell 5. Each thrust ring 7 is sleeved outside one eccentric wheel 9, and can rotate with respect to the eccentric wheel 9. A friction layer 12 is arranged between the thrust ring 7 and the eccentric wheel 9 to help reduce the friction generated by the rotation of the thrust ring 7 with respect to the eccentric wheel 9. When the eccentric wheel shaft 6 rotates, the center of the thrust ring 7 is driven to make circular motion. The thrust ring 7 can roll on a surface in contact with the plunger 3 and push the plunger 3 to move in the plunger cavity 4 to pressurize water or aqueous solution. The rebound structure 2 is preferably a spring, the plunger 3 moves in the plunger cavity 4 under the action of a rebound force of the spring, so as to suck water or aqueous solution. The eccentric wheel 9 and the thrust ring 7 are both located in the shell 5, a space in the shell 5 where the eccentric wheel 9 and the thrust ring 7 are located is also used to be filled with water or aqueous solution. The water or aqueous solution enter center of the shell 5 to reduce the friction force generated by a sliding motion between the thrust ring 7 and the eccentric wheel 9 and between the plunger 3 and the plunger cavity 4, and to take away heat.

In this embodiment, there are three eccentric wheels 9, which employ the integral eccentric wheels 13 and the combined eccentric wheel 14. One eccentric wheel 9 at the central position and one eccentric wheel 19 at one side are integral eccentric wheels 13, and the integral eccentric wheels 13 and the main shaft 8 have a feature of forming material continuity between components, which are preferably integrally machined by using the same blank. One eccentric wheel 9 at another side is the combined eccentric wheel 14. The combined eccentric wheel 14 includes a reinforcing mandrel 15 and an eccentric wheel sleeve 16. A profile curve of the reinforcing mandrel on a projection plane perpendicular to the central line of the main shaft is non-circular. The eccentric wheel sleeve 16 is sleeved and fixed outside the reinforcing mandrel 15 in an interference manner, and the reinforcing mandrel 15 can drive the eccentric wheel sleeve 16 to rotate synchronously. The reinforcing mandrel 15, the integral eccentric wheels 13 and the main shaft 8 are preferably integrally machined by using the same blank, and also have the feature of forming material continuity between the components.

In this embodiment, when the driving mechanism 1 is assembled, prior to installing the eccentric wheel sleeve 16 for the combined eccentric wheel 14, the thrust ring 7 configured to the eccentric wheel 9 located at the central position needs to be sleeved outside the eccentric wheel 9 at the central position after passing through the bearing supporting section 10 and the reinforcing mandrel by using a hole formed in the middle of the thrust ring 7. The sleeving of the remaining thrust rings 7 can be continuously completed after the eccentric wheel sleeve 16 for the combined eccentric wheel 14 in a press-fitting manner.

The cross-sectional size of the reinforcing mandrel 15 is a key design element affecting the stiffness of the eccentric wheel shaft 6. In order to improve the stiffness of the eccentric wheel shaft 6, it is necessary to increase the area of the cross section of the reinforcing mandrel 15 perpendicular to the central line of the bearing supporting section 10 as much as possible on the premise of guaranteeing that the thrust ring 7 can be installed to the integral eccentric wheel 13 at the central position after passing through the reinforcing mandrel 15.

As shown in FIG. 6, the obtained cross-sectional shape of the reinforcing mandrel 15 that meets the application requirements is not a circular shape adopted by the traditional shaft, but a non-circular irregular profile. The profile curve 17 of the reinforcing mandrel on the projection plane perpendicular to the central line of the main shaft surrounds the periphery of the profile curve 18 of the adjacent bearing supporting section on the projection plane perpendicular to the central line of the main shaft, and is also surrounded by the profile curve 19 of the adjacent integral eccentric wheel on the projection plane perpendicular to the central line of the main shaft. In such a design state, the thrust ring 7 can be conveniently installed on the integral eccentric wheel 13 in the middle by conveniently passing through the bearing supporting section 10 and the reinforcing mandrel 15 by using the central hole of the thrust ring. Because the reinforcing mandrel 15 is a non-circular profile, which, compared with a circular section, not only can meet the assembly requirements, but also can significantly increase the cross-sectional area of the reinforcing mandrel 15, so as to effectively improve the structural stiffness. Moreover, the eccentric wheel sleeve 16 can transmit a torque to the reinforcing mandrel 15 without a transmission key and other torque transmission modes, and can move synchronously with the reinforcing mandrel 15.

With the eccentric wheel shaft 6 of this embodiment, compared with the original combined eccentric wheel shaft structure scheme, the flexural deformation at an installation position of a bearing 11 is reduced by half from more than 7 arc seconds to about 3 arc seconds, which meets the use requirements of the bearing 11.

Embodiment 2

As shown in FIG. 8, the different between this embodiment and Embodiment 1 is that in this embodiment, four eccentric wheels 9 are adopted in the eccentric wheel shaft 6, two eccentric wheels 9 in the middle part are integral eccentric wheels 13, and eccentric wheels 9 at both sides close to the bearing supporting sections 10 are combined eccentric wheels 14. During the realization of the manufacturing, after the thrust ring 7 corresponding to the integral eccentric wheel in the middle part is assembled after passing through the close bearing supporting section 10 and the reinforcing mandrel 15 by using the central hole, the assembly of the eccentric wheel sleeve 16 and the corresponding thrust ring 7 are further completed.

Several examples are used for illustration of the principles and implementation methods of the present disclosure. The description of the embodiments is merely used to help illustrate the method and its core principles of the present disclosure. In addition, those of ordinary skill in the art can make various modifications in terms of specific embodiments and scope of application in accordance with the teachings of the present disclosure. In conclusion, the content of this specification shall not be construed as a limitation to the present disclosure.

Claims

1. A high-pressure water pump lubricated by water or aqueous solution, comprising a driving mechanism, at least one plunger, a plunger cavity, and a shell; wherein the driving mechanism comprises an eccentric wheel shaft and thrust rings, the eccentric wheel shaft comprises a main shaft and a plurality of eccentric wheels arranged on the main shaft; each thrust ring is sleeved outside one of the eccentric wheels, each thrust ring and one of eccentric wheels is able to rotate with respect to each other; both ends of the main shaft are bearing supporting sections, the plurality of eccentric wheels and thrust rings are located in the shell, and a space in the shell where the plurality of eccentric wheels and thrust rings are located is also used to be filled with water or aqueous solution; when the plurality of eccentric wheels rotate, the plunger is pushed by the thrust rings to move in the plunger cavity, so as to pressurize the water or aqueous solution; the plurality of eccentric wheels are integral eccentric wheels or combined eccentric wheels, and material continuity is formed between the integral eccentric wheels and the main shaft; each of the combined eccentric wheels comprises a reinforcing mandrel and an eccentric wheel sleeve, a profile curve of the reinforcing mandrel on a projection plane perpendicular to a central line of the main shaft is non-circular, and the eccentric wheel sleeve is sleeved outside the reinforcing mandrel; the reinforcing mandrel is able to drive the eccentric wheel sleeve to rotate synchronously, and material continuity is formed between the reinforcing mandrel and the main shaft;when a number of eccentric wheels in the plurality of eccentric wheels is three, at least one eccentric wheel is located at a central position is the integral eccentric wheel, and at least one eccentric wheel at an outermost side is the combined eccentric wheel; andwhen the number of eccentric wheels in the plurality of eccentric wheels is four, at least two eccentric wheels are located at a central position are the integral eccentric wheels, and at least one eccentric wheel at the outermost side is the combined eccentric wheel.

2. The high-pressure water pump lubricated by water or aqueous solution according to claim 1, wherein the profile curve of the reinforcing mandrel on the projection plane perpendicular to the central line of the main shaft surrounds a periphery of a profile curve of the bearing supporting sections on the projection plane perpendicular to the central line of the main shaft.

3. The high-pressure water pump lubricated by water or aqueous solution according to claim 1, wherein the profile curve of the reinforcing mandrel on the projection plane perpendicular to the central line of the main shaft is surrounded by a profile curve of an adjacent integral eccentric wheel on the projection plane perpendicular to the central line of the main shaft.

4. The high-pressure water pump lubricated by water or aqueous solution according to claim 1, wherein when the eccentric wheel shaft rotates, the thrust rings are able to roll on a surface in contact with the plunger and push the plunger to move in the plunger cavity, so as to pressurize the water or aqueous solution.