EP2723224A1

EP2723224A1 - Pump

Info

Publication number: EP2723224A1
Application number: EP12729596.2A
Authority: EP
Inventors: Volker Block; Tobias Albert
Original assignee: EGO Elektro Geratebau GmbH
Current assignee: EGO Elektro Geratebau GmbH
Priority date: 2011-06-22
Filing date: 2012-06-22
Publication date: 2014-04-30
Also published as: CN103702601A; US20140193260A1; DE102011078017B3; WO2012175652A1

Abstract

The invention relates to a radial pump (12) for water that has a drive motor (15), a pump chamber (19) and an impeller (18) that rotates within the pump chamber (19). The impeller (18) has several impeller blades (35) that are designed elastically in at least some regions and have a fixed bearing located in a region near the rotational axis of the impeller (16). The impeller blades can be elastically bent in a radially outward direction from the fixed bearing against a spring force. (see Fig. 1)

Description

pump

Task and solution

The invention relates to a pump for fluids, in particular an impeller pump.

From WO 2010/034488 A1 a pump for fluids is known, which is designed as a so-called impeller pump or radial pump. This pump has the peculiarity that it can promote both water and air, for example in a dishwasher. Thus, on the one hand, it can promote water for the cleaning process and, on the other hand, air for the drying process. In order to be able to do this efficiently, it is generally described that the conveyor of the pump has compressor blades that are adjustable in the angle of attack. Furthermore, the speeds between the one hand, the promotion of water and on the other hand, the promotion of air significantly and are significantly lower in the first case.

Task and solution

The invention has for its object to provide an aforementioned pump, with which the problems of the prior art can be achieved and in particular an advantageous possibility can be created to use such a pump with an impeller or compressor universal and each very efficient.

This object is achieved by a pump with the features of claim 1. Advantageous and preferred embodiments of the invention are the subject of further claims and are explained in more detail below. The wording of the claims is incorporated herein by express reference. - -

It is provided that the pump is designed as a radial pump or as an impeller pump with a rotating in a pump room rotating compressor or impeller. This is referred to below as Impleller and has a plurality of impeller blades, which are at least partially flexible or elastic or movable. In this case, they have a fixed bearing arranged in a region close to the impeller rotation axis or in a radially inner region. In particular, they are here without pivot with axis or the like. firmly connected by a material connection or a bond or a one-piece production with the impeller. From this fixed storage going radially outward, the impeller blades can be bent or are movable, against a counterforce or spring force. This spring force serves to press the impeller blades in a basic position, which will be explained in more detail below.

Advantageously, this basic position is the position in which the pump promotes a medium of very low density, preferably air, and thus can also be referred to as an air position. This means that the aforementioned spring force tries to push the impeller blades into the air position. In general, then a bending or movement of the impeller blades along the direction of rotation take place, particularly advantageous in the direction of rotation of the impeller by the spring force. This means that in the normal state or the aforementioned basic position, the impeller blades are in the air position, which is to be ensured by the spring force, and wherein the impeller blades are so far as maximum issued.

Alternatively, however, it is also possible that the said basic position is the position in which the pump conveys a medium of high density, preferably liquid or water, and thus also as water position. - - tion can be designated. This means, therefore, that the aforementioned spring force tries to push the impeller blades in the water position, ie counter to the direction of rotation, in which case the impeller blades are so to speak only minimally exposed or are maximally inflected.

In an advantageous embodiment of the invention, the spring force is generated by the elastic properties of the material of the impeller blade itself, ie inherently by the Impellerschaufel itself. For this purpose, it advantageously consists of a corresponding plastic, such as an elastomer with desired elastic properties. The shape of the impeller blade is also to be considered.

It is preferably provided that the impeller blades are monotonically curved radially outward from the aforementioned fixed bearing. This is particularly preferred for its entire course, wherein the curvature may vary slightly in the course, but should not vary their direction of curvature. Advantageously, the curvature is strictly monotonic and / or approximately uniform. In this case, a curvature, as is customary for such impeller pumps, runs radially outward against the direction of rotation. The curvature should be present in all positions, and therefore also in the base position or air position, even if it can be significantly lower here than in another position, for example for conveying a fluid of higher density, for example water, as described below will be explained in more detail.

An angle of the impeller blades to the radial direction may be slightly less than 90 ° in the maximum inwardly bent state, preferably between 70 ° and 80 °. This is especially true for the outer region of the impeller blades due to the aforementioned curvature. In the radially inner region of the impeller blades, this angle can be - - Be considerably lower, for example, only about half amount or 30 ° to 45 °.

In the maximum outwardly bent state of the impeller blades, ie in the aforementioned air position, their angle to the radial direction may be slightly more than 90 °, preferably between 100 ° and 1 10 °. This is especially due to the fact that the impeller blades in this state, which corresponds to the air position, bend in the case of stronger displays and thus change their course along their length.

Although the above-mentioned fixed storage can in some ways allow turning an impeller blade in the manner of a twisting. However, it should be essentially a torque-resistant bearing for itself, so no swivel joint. This can be achieved, for example, by fixing the impeller blade in a certain region of its length, preferably near the inner end, and there with a certain longitudinal section. This determination can be made, for example, by firmly connecting the impeller blade with an imple-bottom disc or impeller cover plate by gluing or one-piece production. A subsequent radially outward subsequent section is then not per se movable, the projecting impeller blade against it over its length from the longitudinal section radially outgoing already. Such a longitudinal section may have a length of, for example, 0.5 cm to 2 cm or be 5% to 30% of the total length, which is regarded as sufficient attachment of the impeller blade and sufficient to specify a certain shape.

Alternatively, it is possible to actually provide a kind of rotation axis for the impeller blade in the radially inner region or on the impeller. However, this has the disadvantage that then via separate means the vorge - called spring force has to be generated, which tries to press the impeller blades in a certain position, advantageous in one of the possible end positions. Furthermore, it is then not so possible that the impeller blades bend over their length or bend slightly straight with appropriate operation. At a torque-resistant storage of Impellerschaufel namely at the same time the spring force, as mentioned above, be achieved by the material properties of the impeller blade and thus a rather uniform curvature.

In an advantageous simple embodiment of the invention, the impeller blades run from the storage radially outward without further guidance, so are free. This means a simple production of an impeller for such a pump with low susceptibility.

Alternatively, a guide of the impeller blades may be provided in the direction along the impeller axis of rotation. This guide should be provided radially outside the attachment of the impeller blade on the impeller, in particular as far outside the impeller or one of its impeller disks. It is possible that the impeller vane between the Impellerbodenscheibe and impeller cover disc is arranged and can make a quasi-guided movement along the direction of rotation, if it has a certain thickness and thereby can not twist or tilt in their longitudinal direction. In this case, it can rest on the said disks or have only a very small distance thereto, so that they can not be undesirably deflected in the direction along the axis of the impeller.

A special possibility for guiding an impeller blade can be achieved in that the impeller blade has an elongated, continuous longitudinal slot, which is at least in a radially outer - -

Area is provided in the direction parallel to the impeller rotation axis. In this longitudinal slot, a sliding element may be arranged, in particular a pin-like sliding element. This can be movable on the one hand in a slot in the Impellerbodenscheibe and / or in the Impellerdeckscheibe, advantageously along the circumferential direction, ie on a particularly advantageous circular path. At the same time, the pin-like sliding element in the longitudinal slot in the Impellerschaufel be displaced and then with their increasing or decreasing curvature, because this is rotatably connected in the radially inner region with the impeller, both in the longitudinal slot of the impeller blade and in said slot in one of the impeller disks.

The provision of such a sliding element on the one hand can cause some additional stiffness in bending or bending the impeller blade, which may be desirable under certain circumstances. Furthermore, tilting or twisting of the impeller blade along its longitudinal extension can be avoided. Finally, end stops for moving the impeller blade can thus be provided, in particular for bending and bending.

While the above-described air position of the impeller blade corresponds to a minimally curved state and the impeller blade is as far as possible out of the impeller and approximated to a radial direction with a relatively straight course, the impeller blade in a maximum curved water position less far or even do not reach out of the impeller at the side. Furthermore, it can be held by a specially provided stop or rest against it. This may in particular be contrary to the spring force mentioned at the outset, since, in the case of conveying water or another high-density fluid, the impeller blades are automatically curved more strongly against the direction of circulation and are pressed inwards into the impeller. That's why the - - Fed spring should be provided, which then just in the case of conveying a low-density fluid again pushes outward in the so-called air position.

Alternatively, it can also be provided that a spring force presses the impeller blades into the abovementioned water position, but not particularly strongly. If a fluid with a lower density is to be conveyed and the impeller assumes the air position, then it turns at a considerably higher speed. As a result, significantly stronger centrifugal forces act on the impeller blades and these are, in contrast to the aforementioned, inwardly pressing spring force, continue on or bend and stand further out of the impeller and thus take the air position. This can also be reinforced by the fact that areas of greater mass or even additional weights are provided on the outer areas of the impeller.

In a further embodiment of the invention, an aforementioned inner spring force of the impeller blade can be given over a substantial part of its length, advantageously over its entire length. It is possible to manufacture the entire impeller blade from a single material and it may also have a cross-section that is substantially uniform over its length. A lighter bending or certain spring properties of an impeller blade can be adjusted both by choosing their production material and by the cross section, for example by recesses are provided, in particular along the impeller blade.

If the impeller blade projects out of the impeller in the air position, this can be done with about 20% to 50% of its length, for example. In this case, provide sufficient radial space in the pump room of the pump. In the maximum curved state, in particular in - - The water position, an Impellerschaufel little or no sticking out of the impeller.

These and other features will become apparent from the claims but also from the description and drawings, wherein the individual features each alone or more in the form of sub-combinations in an embodiment of the invention and in other fields be realized and advantageous and protectable Represent embodiments for which protection is claimed here. The subdivision of the application into intermediate headings and individual sections does not limit the general validity of the statements made thereunder.

Brief description of the drawings

An embodiment of the invention is shown schematically in the drawings and will be explained in more detail below. In the drawings show:

1 is a schematic representation of a pump with an impeller according to the invention,

2 is an oblique view of the impeller with impeller blades both in an air position and in a water position,

Fig. 3 is a sectional view through the impeller of FIG. 2 is a detailed representation of the course of the impeller blades of the air position and in the water position and

Fig. 4 is a plan view of a modification of the impeller blades similar to Fig. 3 with solid impeller blades without longitudinal slots.

Detailed description of the embodiments - -

In Fig. 1, a pump assembly according to the invention 1 1 is shown in a highly schematic representation. This pump assembly 1 1 is installed in a water-conducting household electrical appliance, in particular in a dishwasher or washing machine, advantageously under the washing chamber.

The pump assembly 1 1 has a pump 12 which has a pump housing 13 and a motor 15, the motor shaft 16 extends into the pump housing 13 and a conveyor 18 carries, which rotates in a pump chamber 19 in the interior of the pump housing 13. The connection of pump housing 13 and motor 15 is advantageously fixed, for example by a detachable screw connection.

The conveyor 18 is advantageously designed conventionally in the version shown here and corresponds for example to a conveyor, as it is known from DE 19903951 A1, to which reference is expressly made in this regard. Furthermore, here is the representation of the dimension of the pump housing 13 and the other components not to scale.

The pump housing 13 or the pump chamber 19 has a central and axial pump access 21. Furthermore, a pump outlet 23 is provided, which is arranged laterally and radially. Within the pump chamber 19 extends a heater 28 with heating connections 29, which are led out of the pump housing 13. The illustrated heater 28 is formed except for a corresponding, not shown interruption for the pump outlet 23 is substantially cylindrical and close to or on the wall of the pump chamber 19 circumferentially. It may be an initially mentioned thick film heater, with heating elements on at least one of its sides, advantageously the outer - - side, are arranged, possibly also on the other or on both sides.

In Fig. 2, an impeller 18 is shown in an enlarged oblique view from above. It can be seen here that the impeller 18 has an impeller bottom disk 30 and an impeller cover disk 32, as is known per se. The Impellerbodenscheibe 30 is substantially flat and the Impellerdeckscheibe 32 rising, as can be seen in the side view of FIG. In the middle of the impeller cover disk 32 there is a suction opening 33, as is known per se. The above-described motor shaft 16 is fixed in the Impellerbodenscheibe 30. The direction of rotation of the impeller 18 in Fig. 2 is counterclockwise.

The impeller 18 has five Impellerschaufeln 35, which are shown in Fig. 2 on the one hand as impeller blades 35 in the maximum far bent state. This condition corresponds to an air position of the impeller blades 35 mentioned at the outset. On the other hand, the impeller blades are also represented by the reference numeral 35 'at least in the lower region. In connection with FIG. 3, it becomes clear that here these impeller blades 35 'are in the water position and are curved as far inward as possible or are curved at most to a maximum extent. Due to a stop, which is not shown here, they only insignificantly exceed the diameter of the impeller 18 or the impeller disk 30, 32. Care should be taken during the construction of the impeller 18 or the entire pump 12, in particular together with the heater 28 be that the impeller blades 35 in the maximum far bent position shown in FIG. 2 does not grind inside the pump housing 13 and a heater 28.

In Fig. 3 is shown in slight magnification without the impeller cover 32, as the impeller blades 35 are formed. In the radially inner In the region or at the radially inward end, they have a fastening region 37, in which they are firmly connected to the impeller base disk 30 over a certain length. This solid connection can be a one-piece production on the one hand and on the other hand a sticking or other, stable and permanent fastening, for example by means of a positive connection such as plugging or .. From hatched illustrated mounting portion 37 of the impeller blade 35 extends to the outside and is no longer with the Impellerbodenscheibe 30 connected. In this case, the free area of the impeller blade 35 may have a very small distance to the Impellerbodenscheibe 30, in particular to the impeller cover 32, especially in the radially outer region, for example, a few tenths of a millimeter.

In the impeller blade 35, a shape or predetermined curvature is represented by the reference numeral 35 as in the air position. This means that the impeller blade 35 is present in the air position without external force influencing. If it is bent in the direction of rotation of the impeller 18 counterclockwise counter to this direction of rotation, ie to the right, so it takes the more curved water position 35 'a. The curvature shown results in particular when the impeller 18 promotes water in the pump 12 and the water resistance or the much greater force necessary for this purpose, the impeller blade 35 just more curved. As soon as this larger force is removed, the impeller blade 35 moves back into the air position as an impeller blade 35 by its own spring force.

As a guide means for guiding the impeller blade 35, a slot 39 is provided in the Impellerbodenscheibe 30, which extends over a region near the outer periphery and thereby almost reaches the impeller 35 in the air position and the impeller 35 'in the water position , In the slot 39 is a pin-like sliding member 40th - - stored, which can be moved along the slot 39. Advantageously, there is a corresponding slot above the slot 39 on the underside of the impeller cover plate 32, so that the sliding element is secured on both sides. For safe and tilt-free guidance, the slider 40 may have a kind of elongate, corresponding to the slot 39 slightly curved carriage body with pin for guiding in one or both slots of the impeller 30 and 32, wherein two carriage body are then connected by the pin. This pin of the sliding member 40 runs, as shown, in a longitudinal slot 36 in the impeller blades 35. The slots 36 and 39 can be formed together with sliding member 40 so that the sliding member 40 in the air position of the impeller blade 35 at the bottom of the slot 39 and as far as possible radially inward on the longitudinal slot 36 of the impeller blade 35 is located. In the water position of the impeller blade 35 'is the slider 40 at the top of the slot 39 and at most far outward on the longitudinal slot 36. This thus defines the maximum strongly curved state of the impeller vane 35'. In possible intermediate positions, the sliding element 40 defines, on the one hand, a certain guidance or predetermined shape of the impeller blade 35. Furthermore, as shown in FIG. 3, it can represent, as it were, end stops for the water position on the one hand and the air position on the other hand. Namely, the impeller vane 35 can not be bent more in the direction of rotation nor against the direction of rotation of the impeller 18.

Furthermore, it should be said with regard to the two positions according to FIG. 3 that due to the lever arm of the force application to the impeller blade, the bending or curvature thereof takes place mainly in the inner region near the fastening region 37. The exact shape of the curvature or the course of the curvature can be influenced by various adjustable material properties of the impeller blade 35 as well as by shaping, for example by the longitudinal slots - -

36 or the like., For example, by changing in the longitudinal direction cross-section.

It should also be noted for the impeller blades 35 that while on the one hand, as can be seen from FIG. 1, they should have a shape such that they run substantially close to the impeller base disk 30 and the impeller cover disk 32, in both positions. However, care should then be taken to ensure that the distance between the two impeller disks 30 and 32 in the area where the impeller blades 35 are curved in and out between them is such that the movement of the impeller blades is not impaired.

As an alternative to a curvature of the impeller blade 35, as it were, predetermined by shaping in the air position corresponding to FIG. 3 with minimal curvature, it could also be provided that the impeller blade 35 'assumes the water position in the normal or unloaded state and is therefore curved to a maximum extent , If 12 air are to be pumped with the pump, the speed at the motor 15 is greatly increased, for example, doubled or tripled, which greatly increases the centrifugal forces acting on the impeller blades 35 and thereby cause them to bend out more strongly according to FIG Set up in the air position. Under certain circumstances, this can be intensified by providing regions of higher mass in the area of the outer free ends of the impeller blades or even additional weights are provided. If water is then pumped again in the pump 12 at a lower number of revolutions, then the impeller blades 35 on the one hand move back into the strongly curved water position due to the decreasing centrifugal force and, on the other hand, due to the predetermined shape.

In Fig. 4 is shown in a modification for an impeller 1 18, as arranged on an Impellerbodenscheibe 130 impeller blades - -

135 solid or without the longitudinal slots corresponding to FIG. 3 may be formed. This means that the impeller blades 135 have no guidance for their movement between the minimally curved and as far as possible exposed air position on the one hand and the maximum strongly curved to the right water position as Impellerschaufeln 135 \ Only a first stop 141 for the air position is provided on the Impellerbodenscheibe 130. Similarly, a second water position stop 142 is provided on the impeller bottom disk 130. These stops 141 and 142 cause the Impellerschaufel 135 is similarly limited in their movement or curvature as by the sliding member 40 together with slot 39 as shown in FIG. 3rd

This formation of the impeller disks 130 and 132 and the impeller blades 135 itself is somewhat simpler than in accordance with FIG. 3. The stoppers 141 and 142 can either extend only slightly over the impeller base disk 130 in order to cause as little water resistance as possible or cause turbulence. Alternatively, they can also extend over the significant height or the entire height of the impeller blades 135, in particular toward the opposite impeller cover disk 132. Thus, on the one hand, they ensure a good and torsion-free installation of the impeller blades 135. On the other hand, they can also serve to connect the two impeller disks 130 and 132 together.

With respect to a possible preforming or pre-curvature of the guide vanes of the embodiment of FIG. 4, the same is to say as in Fig. 3, so there are the same possibilities. The omitted in the embodiment of FIG. 4 guide by sliding and slot does not change anything.

Claims

claims

1. Pump for fluids with a drive motor, a pump chamber and a rotating in the pump chamber impeller or rotating compressor, wherein preferably the pump is designed as a radial pump, wherein the impeller has a plurality impeller blades, characterized in that the impeller blades at least partially flexible or are designed to be elastic or movable and have arranged in a region located near the impeller axis of rotation fixed storage, where they are from this fixed storage radially outwardly bendable or movable against a spring force.

2. Pump according to claim 1, characterized in that the impeller blades are bendable or movable in the direction of rotation of the impeller against the spring force.

3. Pump according to claim 1 or 2, characterized in that the spring force is inherently given by the elastic properties of the material of the impeller blade.

4. Pump according to one of the preceding claims, characterized in that the impeller blades of the fixed bearing radially outwardly, in particular in their entire course, are monotonously curved, preferably strictly monotonous and / or approximately evenly, in particular a curvature radially outward runs counter to the direction of rotation.

5. Pump according to claim 4, characterized in that the angle of the impeller blades to the radial direction in the maximum after inside bent state is slightly less than 90 °, preferably between 70 ° and 80 °.

6. Pump according to claim 4 or 5, characterized in that the angle of the impeller blades to the radial direction in the maximum outwardly bent state is slightly more than 90 °, preferably between 100 ° and 1 10 °.

7. Pump according to one of the preceding claims, characterized in that the fixed bearing is a torque-resistant mounting.

8. Pump according to one of the preceding claims, characterized in that the fixed bearing of the impeller blades occupies the radially innermost portion of the impeller blades or is arranged there, preferably as a torque-fixed bearing according to claim 7 with a determination of a longitudinal section of the impeller blades of at least 0.5 cm.

9. Pump according to one of the preceding claims, characterized in that the impeller blades starting from the torque-fixed storage radially outward without further guidance.

10. Pump according to one of claims 1 to 8, characterized in that radially outside the attachment of the impeller blade guidance of the impeller blades is provided in the direction along the impeller rotation axis, preferably by a Impellerbo- disc and a Impellerdeckscheibe, between which arranged the impeller blades can or stand out.

1 1. A pump according to claim 10, characterized in that an impeller blade has an elongated continuous longitudinal slot in a radially outer region in the direction parallel to the impeller rotation axis, wherein in the elongated slot, a sliding element, in particular a pin-like sliding element, is arranged in a slot at least in the Impellerbodenscheibe and / or in the Impellerdeckscheibe along the circumferential direction is movable and at the same time in the longitudinal slot in the Impellerschaufel is displaceable.

12. Pump according to one of the preceding claims, characterized in that the impeller blade has a maximum curved water position for conveying water or other liquid, wherein in particular the impeller blade rests by the force exerted by the pumped water force against a stop.

13. Pump according to one of the preceding claims, characterized in that the impeller blade assumes a position of air in a minimal curved state and is spring-loaded and preferably rests against a stop, in particular, the spring force is generated by their own elastic properties.

14. Pump according to one of the preceding claims, characterized in that an inner spring force of the impeller blade counter to the direction of rotation acts.

15. Pump according to one of the preceding claims, characterized in that an internal spring force of the impeller blade given by correspondingly elastic or flexible properties of the impeller blade over a substantial part of their length are, wherein preferably the entire impeller blade consists of a single material and over its length also has a substantially constant cross-section.

Pump according to one of the preceding claims, characterized in that the impeller blades in the minimally curved state, in particular in the air position according to claim 13, protrude from the impeller or between a Impellerboden- disc and an impeller cover, preferably with about a quarter to the Half of their length.