US20110123357A1

US20110123357A1 - Floatable pump unit

Info

Publication number: US20110123357A1
Application number: US12/920,466
Authority: US
Inventors: Michele Leone; Riccardo Dal Canto; Susanne Wiatr Borg
Original assignee: Grundfos Management AS
Current assignee: Grundfos Management AS
Priority date: 2008-03-07
Filing date: 2009-02-21
Publication date: 2011-05-26
Also published as: WO2009109305A2; EP2098732A1; CN101960147B; CN101960147A; WO2009109305A3

Abstract

A pump assembly is buoyant and includes an electrical drive motor (16), a centrifugal pump driven by the motor, and an assembly housing (2) accommodating the drive motor (16) and the centrifugal pump. Moreover, the pump assembly includes at least one inlet opening (8) which is arranged below the fluid surface (6) in the floating condition, and at least one outlet opening (10, 12). The assembly housing (2) is arranged such that on reaching a contact surface, the assembly housing changes its alignment with respect to the floating position.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Section 371 of International Application No. PCT/EP2009/001261, filed Feb. 21, 2009, which was published in the English language on Sep. 11, 2009, under International Publication No. WO 2009/109305 A3 and the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a buoyant pump assembly, with the features specified in the preamble of the independent claim(s).
Buoyant pumps, which, floating on the fluid surface of containers and waters, suck fluid or water from these containers and waters, are counted as belonging to the state of the art. The application of such pumps has been found to be problematic, if the containers or waters are formed in a closed manner, and the fluids to be sucked are intermingled with solid matter particles. The reason for this is due to the fact that these pumps sink into a region of the container or water which is close to the bottom, when the fluid level or water level sinks on account of the pump work, in which region the share of solid matter particles as a rule is significantly increased. By way of this, the danger of the solid matter penetrating into the pumps via the inlet openings and clogging them is significantly increased, which, as the case may be, entails repairs, and at the very least, extensive cleaning work.

BRIEF SUMMARY OF THE INVENTION

Against this background, it is an object of the present invention to provide a buoyant pump assembly which is suitable for the application in fluids intermingled with solid matter particles, wherein the danger of a clogging of the pump assembly is at least significantly reduced.
The above object is achieved by the present invention with a pump assembly with the features specified in the independent claim(s), wherein advantageous further formations of this pump assembly are to be deduced from the dependent claims, the subsequent description, as well as the drawings.
The pump assembly according to the present invention is buoyant and preferably comprises an electric drive motor, a centrifugal pump driven thereby, and an assembly housing which accommodates the drive motor and the centrifugal pump. Furthermore, the pump assembly comprises at least one inlet opening, which in the floating condition is arranged below the fluid surface, and at least one outlet opening. According to the present invention, the assembly housing is designed and arranged, such that on reaching a contact surface, it changes its alignment with respect to the floating position, wherein position-controlled switch means are provided within the assembly housing,
Hereby, the present invention is based on the idea of designing and arranging the assembly housing of the pump assembly such that when it reaches a contact surface, for example a base of a container or a bed of a water, on account of a fluid level sinking due to pump work, it does not find any firm support there. For example, it may not be situated there in a stable equilibrium, and therefore changes its alignment with a further sinking fluid level, wherein the switch means also change their position with the alignment change of the assembly housing, and preferably switch off the pump assembly, or switch it into a condition, in which such solid matter particles are kept back or, as the case may be, may also be delivered with the fluid. The alignment changes of the assembly housing, and the switch means which are located therein, are typically effected by way of the assembly housing inclining with respect to its floating position. The at least one inlet opening of the pump assembly is usefully arranged on the assembly housing such that when the assembly housing reaches the contact surface, this inlet opening is arranged in the fluid above sediment of solid matter particles which is to be expected in a container or water. In this manner, with the pump assembly according to the present invention, one may advantageously prevent the centrifugal pump from suctioning solid matter particles in an excessive manner, which, as the case may be, may clog the pump assembly. A further advantage of the pump assembly according to the present invention is to be seen in the fact that this design prevents the centrifugal pump from running dry. Inasmuch as this is concerned, the pump assembly according to the present invention has a very high operating reliability.
In order for the assembly housing to be able to change its alignment with respect to its floating position on reaching a contact surface, the assembly housing is preferably designed in a manner such that it may tilt about an axis which is arranged between the assembly housing and the contact surface, transversely to the buoyancy direction of the fluid. After the tilting, the assembly housing may come to rest on the contact surface in a surfaced manner, in a stable tilt position. For this, the assembly housing advantageously comprises a tilt surface on a section which is at the bottom in the floating condition. The tilt surface within the context of the present invention, is to be understood as the surface with which the assembly housing comes to lie on the contact surface after the tilting, wherein the term tilt surface is not limited to a surface which is physically formed on the assembly housing, but also those imagined surfaces which are formed by at least two points which are distanced on the outer side of the assembly housing and on which the assembly housing lies on the contact surface in a tilted position.
Preferably, one envisages the assembly housing tapering downwards in a section which is at the bottom in the floating condition. For example, the assembly housing, in this lower section, tapers in a pointed manner toward the bottom. Thus, a lower section of the assembly housing may, for example, be designed in a cone-like or wedge-like manner, wherein the tip of the thus formed cone or wedge is usefully the part of the assembly housing which firstly reaches a contact surface in a container or water, given a reducing fluid level. Such a tip must be adequately blunt, in order prevent a penetration into the contact surface, but must be adequately pointed, in order to ensure a tilting. The tip then forms a tilt axis or part of a tilt axis, about which the assembly housing may be tilted. The outer side of the tapering lower section of the assembly housing may hereby form the tilt surface, on which the assembly housing lies on the contact surface after the tilting. The lower section of the assembly housing usefully tapers in a manner such that the assembly housing, as the case may be, may not get stuck in a morassy subsurface located on the container or the water bed in the floating position, and may not loose its alignment in this manner.
In order to prevent the section of the assembly housing which is at the bottom in the floating position, from getting stuck in such a manner, the lower end of this section of the assembly housing is advantageously flattened or rounded. In this context, one preferred further formation of the pump assembly according to the present invention envisages the lower side of the assembly housing being designed in a convexly curved manner. The assembly housing may, for example, taper in a calotte-like manner on the section which is at the bottom in the floating position, and be tilted about the apex of its curvature. Here, the outer side of the curved region, may form a part of the tilt surface which comes to rest on a contact surface.
In a further advantageous design of the pump assembly, a preferably downwardly directed projection may be formed on the lower side of the assembly housing. This projection is usefully arranged and designed in a manner such that given a pump assembly sinking in a container or water, firstly a contact surface formed there is reached, wherein the assembly housing then tilts about the free end of this projection with a further sinking. In this case, the tilt surface of the assembly housing is typically formed by an imaginary surface, on which the free end of the projection and at least one further point of the outer side of the assembly housing, said point being distanced to the projection, lie. The projection is particularly advantageously arranged on the lower side of the assembly housing, in a manner such that it is distanced to the centre of gravity of the pump assembly in the direction of the fluid surface, in the floating position of the pump assembly, so that when the projection has reached the contact surface, the weight of the pump assembly exerts a tilting moment on the pump assembly. By way of this, one succeeds in the assembly housing always tilting to the same side. Accordingly, the assembly housing has an unambiguously defined tilt surface with this design.
Preferably, an inclination switch is provided as position-controlled switch means, which is designed and arranged in a manner such that it switches off the centrifugal pump given an alignment of the assembly housing which is different from the alignment in the floating condition. The inclination switch may comprise a component which is movably mounted in the switch, wherein the component is designed and arranged in a manner such that in the floating position of the pump assembly, it sets the inclination switch into a position switching on the centrifugal pump, and with an alignment change of the assembly housing, it changes its position, and by way of this switches the inclination switch into a position switching off the centrifugal pump. In order for the component arranged in the inclination switch in a movable manner to have a good movability, it is advantageously designed in a rolling manner, and preferably as a ball.
In a further preferred design, the assembly housing in a region arranged above the fluid surface in the floating condition, comprises at least one outlet opening aligned perpendicular to the fluid surface. This outlet opening may be formed on a connection which is provided for fastening a flexible tube conduit, with which the fluid may be led away out of the container or water. Furthermore, the pump assembly according to the present invention, with an outlet opening arranged in such a manner, may for example also form a spring well. For this, the pump assembly may be applied floating in a pool or a pond, and with a switched-on centrifugal pump, may produce a jet of water which exits from the outlet opening and extends perpendicular to the water surface.
Depending on the space available in the container, it may also be advantageous if the outlet opening is formed at a different location of the assembly housing, as the case may be, with a different alignment. Thus, the pump assembly according to the present invention may advantageously comprise at least one outlet opening which in the floating condition is aligned essentially parallel or also obliquely to the fluid surface.
The assembly housing particularly preferably comprises at least two outlet openings, wherein one of the two outlet openings may be selectively conducingly connected to the pressure side of the centrifugal pump. Accordingly, means are provided, with which a flow path from the exit of the pump to the outlet opening may be closed, whilst the flow path to the other outlet opening is opened. In this context, one may apply a 3/2-way valve for example.
In order to be able to use the pump assembly according to the present invention, as the case may be, to also almost completely empty a container, a part of the assembly housing forming the tilt surface is formed in a removable manner, and covers a stand surface formed on the pump assembly. With this design, only the part of the assembly housing which forms the tilt surface and which for example is connected to the remaining assembly housing via a locking connection for example, needs to be released, whereupon the pump assembly, with the stand surface which is then freed, may stand on a contact surface formed in a container or water, without changing its alignment and thus its switch position.
In order for the pump assembly according to the present invention not to change its position on the fluid surface in the floating condition, a fastening means may advantageously be formed on the section of the assembly housing which is at the bottom in the floating position. With regard to the fastening means, it may, for example, be the case of a tab or eyelet, on which for example at least one ground anchor may be formed.
In a further advantageous design, the pump assembly comprises handling grips. The handling grips may be arranged on the outer side of the assembly housing, or may be formed by the assembly housing itself, e.g. in the form of undercuts formed on the assembly housing.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.

In the drawings:

FIG. 1 is a side elevation view of a buoyant pump assembly according to a preferred embodiment of the present invention;

FIG. 2 is a second side elevation view of the pump assembly shown in FIG. 1;

FIG. 3 is a top perspective view of the pump assembly according shown in FIG. 1;

FIG. 4 is a bottom perspective view of the pump assembly according shown in FIG. 1;

FIG. 5 is a cross-sectional elevation view of the pump assembly shown in FIG. 1;

FIG. 6 is a partially exploded side elevation view of the pump assembly shown in FIG. 1, with a removed lower section of the assembly housing;

FIG. 7 is a side elevation view of the pump assembly shown in FIG. 6, with the pump assembly standing on a contact surface;

FIG. 8 is a side elevation view of the pump assembly shown in FIG. 1 in a first tilted position; and

FIG. 9 is a side elevation view of the pump assembly shown in FIG. 1 in a second tilted position.

DETAILED DESCRIPTION OF THE INVENTION

Certain terminology is used in the following description for convenience only and is not limiting. The words “lower,” “bottom” and “top” designate directions in the drawings to which reference is made. The word “outwardly” refers to a direction away from the geometric center of the device, and designated parts thereof, in accordance with the present invention. Unless specifically set forth herein, the terms “a,” “an” and “the” are not limited to one element, but instead should be read as meaning “at least one.” The terminology includes the words noted above, derivatives thereof and words of similar import.
Referring to the drawings in detail, wherein like numerals indicate like elements throughout the several views, FIGS. 1-9 show a pump assembly according to a preferred embodiment of the present invention. The pump assembly preferably comprises an assembly housing 2. The pump assembly is designed in a floating manner, wherein an assembly housing part 4 a, to the most part, is arranged above a fluid surface 6 in the floating condition, while an assembly housing part 4 b is completely immersed into the fluid. Buoyancy chambers 7 a, 7 b (FIG. 5) filled with air, are formed in the assembly housing part 4 a, for creating the floating ability. The weight distribution in the pump assembly is such that a longitudinal axis A of the assembly housing 2 is aligned essentially perpendicularly to the fluid surface 6, in the floating position of the pump assembly.
The assembly housing parts 4 a, 4 b are designed essentially rotationally symmetrical to the longitudinal axis A. The upper assembly housing part 4 a has a larger outer diameter than the lower assembly housing part 4 b, wherein an undercut 9 (FIG. 4) is formed on the upper assembly housing part 4 a at its region projecting beyond the outer diameter of the assembly housing part 4 b. Grips 11 for handling the pump assembly, are arranged in this undercut 9, distributed over the periphery.
Two rows of inlet openings 8 distanced to one another in the direction of the longitudinal axis A are arranged distributed over the whole periphery of the lower assembly housing part 4 b. Two outlet connection pieces 10, 12, which form the outlet openings of the pump assembly, are formed on the upper assembly housing part 4 a. The outlet connection piece 10 extends concentrically to the longitudinal axis A to the outside, on the upper assembly housing part 4 a, while the outlet connection piece 12 extends outwardly, radially to this longitudinal axis A, in a region of the upper assembly housing part 4 a, which in the floating condition of the pump assembly, lies below the fluid surface 6. The outlet connection pieces 10, 12 are each provided with outer threads, so that flexible conduit leads, as the case may be, may be connected to these outlet connection pieces via standard couplings. The outlet opening of the outlet connection piece 10 is closed by a closure cap 14 screwed onto the outlet connection piece 10. The inlet opening of the outlet connection piece 12 may also be selectively closed with this closure cap 14.
A centrifugal pump 16 with an impeller 20 and which is driven by an electrical drive motor 16, is arranged in the lower assembly housing part 4 b. An electrical connection 21, is arranged on the outer side of the lower assembly housing part 4 b for supplying the drive motor 16 with electricity, to which electrical connection an electricity supply cable and control cable may be connected.
Fluid may be sucked by the centrifugal pump out of a container or water, through the inlet openings 8, and from there, via a flow path characterized by a direction arrow B, to the pump entry.
One part of the flow path at the exit side of the centrifugal pump, is formed by a rotary slide valve 20, which is mainly arranged in the upper assembly housing part 4 a. The rotary slide valve 20 preferably comprises a hollow-cylindrical rotary slide 22, which on its periphery side, comprises a first recess 24 and a second recess 26. The position of the recess 24 corresponds with the flow channel through the outlet connection piece 12, while the position of the recess 26 corresponds with the position of a flow channel leading to the outlet connection piece 10. The rotary slide is mounted in the upper assembly housing part 4 a in a rotationally moving manner. The recesses 24, 26 are arranged offset to one another in the peripheral direction by an angle of 90°. The rotary slide 20, via an operating part 28 arranged on the outer side of the upper assembly housing part 4 a which is firmly connected to the rotary slide 20, may be rotated into a first position, in which the recess 24 releases a flow path into the outlet connection piece 12, but the flow path to the outlet connection piece 10 is simultaneously closed. The flow path from the exit of the centrifugal pump to the inlet opening formed on the outlet connection piece 12, which arises in this position of the rotary slide, is characterized in FIG. 3 by the direction arrow C. In a position of the rotary slide 20 rotated by 90°, the flow path to the outlet connection piece 12 is closed, and the flow path to the outlet connection piece 10 is released.
An inclination switch is preferably arranged above the electrical drive motor 16 in the floating position of the pump assembly, and comprises a dish-like running surface 30, a ball 32, and a microswitch 34. The microswitch 34 in the floating position of the pump assembly, is arranged below a recess formed on the running surface 30. In the floating position, the metallic ball 32, which may be designed as a solid ball or a hollow ball, lies above the recess of the running surface 30, and presses onto the microswitch 34, which by way of this, is set into a switch position in which the centrifugal pump is switched on. If the alignment of the assembly housing 2 transversely to its longitudinal axis A changes, then the ball 32 runs on the running surface 30 away from the recess, and accordingly no longer presses onto the microswitch 34, which on account of this switches into a position, switching off the centrifugal pump.
The assembly housing part 4 b, in the floating position, firstly tapers downwards in a conical manner and then merges into a lower section 36 which is convexly curved outwards in a calotte-like manner. A projection 38 extends, outwardly concentrically to the longitudinal axis A of the assembly housing 2, on the outer side of this section 36. A recess 40 is formed on this projection 38, which thus forms a tab. This tab forms a fastening means, with which the floating pump assembly may be fastened on the base of a container or water, by way of a cable or chain, so that it may no longer change its position in the floating position. Moreover, the upper assembly housing part 4 a likewise comprises a multitude of fastening tabs 42, which are distributed on its outer periphery and by way of which the pump assembly may likewise be fastened via cables or wires.
The manner of functioning of the pump assembly is as follows:
The pump assembly floats in a container or water in a floating position, in which the longitudinal axis A of the assembly housing 2 is aligned perpendicularly to the fluid surface 6. In this floating position, the ball 32 of the inclination switch is arranged directly above the recess formed on the running surface 30, and presses the microswitch 34 arranged below the recess, into a switch position switching on the centrifugal pump. Accordingly, the centrifugal pump delivers fluid out of the container or water. By way of this, the fluid surface 6 of the container or water sinks, and thus the pump assembly contacts a contact surface 44 formed on the bed of a container or water, up to the projection 38 which is arranged on the lower section 36 of the lower assembly housing part 4 b. The pump assembly finds no firm support on the contact surface 44, and tilts over the edge of the projection 38 transversely to the longitudinal axis A of the assembly housing 2, to the side (FIG. 8 and 9). Here, the edge of the projection 38 and a region of the lower section 36 of the lower assembly part housing 4 b thereby forms a tilt surface, on which the pump assembly lies on the contact surface 44. With a certain tilt angle α, the ball 32 of the inclination switch moves on the running surface 30 to the outside, away from the recess formed therein, and thus no longer contacts the microswitch 34, which thereupon switches off the centrifugal pump. It is predominantly the design of the inclination switch which determines at which height the fluid surface 6 above the contact surface 44, the centrifugal pump is switched off by the inclination switch. Thus, the inclination switch may be designed in a manner such that the ball 32 only leaves its position contacting the microswitch 34 with a larger inclination angle α, and thus switches off the centrifugal pump at a lower fluid height above the contact surface 44 (FIG. 9).
In order to almost completely empty containers or waters with the pump assembly according to the present invention, the lower section 36 of the assembly housing part 4 b is designed in a removable manner after the release of a locking connection via a press button 46, wherein after the removal, it releases an essentially plane stand surface 48 which is formed on the assembly housing part 4 b and which is aligned normally to the longitudinal axis A of the assembly housing (FIG. 6). The pump assembly with this plane stand surface 48 may stand on a contact surface 44, without tilting over (FIG. 7) and thus without switching off.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.

Claims

1-12. (canceled)

13. A buoyant pump assembly with an electrical drive motor (16), a centrifugal pump driven by the motor, and an assembly housing (2) accommodating the motor and centrifugal pump, at least one inlet opening (8) in a floating condition being arranged below a fluid surface (6), and at least one outlet opening (10, 12), wherein the assembly housing (2) is arranged such that on reaching a contact surface (44), the assembly housing (2) changes alignment with respect to the floating position, and position-controlled switch means are provided within the assembly housing (2).

14. The pump assembly according to claim 13, wherein the assembly housing (2) comprises a tilt surface on a section which is at a bottom in the floating condition.

15. The pump assembly according to claim 13, wherein the assembly housing (2) tapers downwardly in a section which is at a bottom in the floating condition.

16. The pump assembly according to claim 15, wherein a lower side of the assembly housing (2) is curved in a convex manner.

17. The pump assembly according to claim 15, wherein a projection (38) is formed on the lower side of the assembly housing (2).

18. The pump assembly according to claim 13, wherein an inclination switch is provided as the switch means, which is arranged in a manner such that the inclination switch switches off the centrifugal pump given an alignment of the assembly housing (2) which differs from the alignment in the floating condition.

19. The pump assembly according to claim 13, wherein the assembly housing (2) comprises at least one outlet opening (10) aligned perpendicularly to the fluid surface (6), in a region which is arranged above the fluid surface (6) in the floating condition.

20. The pump assembly according to claim 13, wherein the assembly housing (2) comprises at least one outlet opening (12) aligned essentially parallel to the fluid surface (6) in the floating condition.

21. The pump assembly according to claim 13, wherein the assembly housing (2) comprises at least two outlet openings (10, 12), wherein one of the two outlet openings (10, 12) is selectively flow-connectable to a pressure side of the centrifugal pump.

22. The pump assembly according to claim 13, wherein a part (36) of the assembly housing (2) forming a tilt surface is designed in a removable manner and covers a stand surface (48) formed on the pump assembly.

23. The pump assembly according to claim 22, wherein a fastening means is formed on the part (36) of the assembly housing (2) which is at a bottom in the floating condition.

24. The pump assembly according to claim 13, wherein the pump assembly comprises handling grips (11).