EP3230595A1

EP3230595A1 - Arrangement of an impeller on a rotating part and method for producing the arrangement

Info

Publication number: EP3230595A1
Application number: EP15831133.2A
Authority: EP
Inventors: Stefan Roessler; Michael RUEDENAUER
Original assignee: Ziehl Abegg SE
Current assignee: Ziehl Abegg SE
Priority date: 2014-12-12
Filing date: 2015-12-01
Publication date: 2017-10-18
Anticipated expiration: 2035-12-01
Also published as: US20170321706A1; EP3230595B1; SI3230595T1; DE102014225688B3; CN107532602B; WO2016091256A1; US10619641B2; ES2879961T3; CN107532602A

Abstract

An arrangement of an impeller (3) on a rotating part, preferably on an electric motor (1), in particular on an external rotor motor, wherein the torque of the motor (1) is transmitted to the impeller (3) by a rotationally secure connection between the rotor (2) of the motor (1) and the impeller (3) or its impeller hub (4), and wherein the connection is created by means of a press fit between the impeller hub (4) and the rotor (2), with integration of a sleeve (6) which is preferably securely assigned to the impeller hub (4) and which takes up mechanical stresses, is characterized in that the sleeve (6) is polygonal and is pressed onto the surface of the rotor (2), with at least minor deformation, forming axial contact surfaces. Also specified is a method for producing such an arrangement.

Description

ARRANGEMENT OF A WHEEL ON A ROTATING PART AND METHOD FOR PRODUCING THE ARRANGEMENT

The invention relates to an arrangement of an impeller on a rotating part, preferably on an external rotor motor. By way of example, the rotating part can be an executed shaft of an internal rotor motor or a hub or disk, for example in the case of a belt drive. In any case, the term "rotating part" is to be understood in the broadest sense, for the sake of simplicity, the following is the arrangement of an impeller on an electric motor, in particular on an external rotor motor.

In the generic arrangement, the torque of the motor is transmitted to the impeller through a non-rotatable connection between the rotor of the motor and the impeller or its impeller hub. The connection is realized by means of an interference fit (press fit) between the impeller hub and the rotor, with the inclusion of a pulley hub permanently assigned, mechanical stress receiving Ronde. For a fixed assignment, it should be noted that the impeller or the impeller hub and the Ronde can be two independent parts, wherein the pressing / mounting creates a whatever connection to be defined. Furthermore, the invention relates to a method for producing such an arrangement.

The terms "impeller" and "external rotor motor" or "external rotor" are to be understood in the broadest sense, in particular, the impeller may be the impeller (axial impeller) of a fan, the impeller being non-rotatably connected to the rotor (cf. DE 10 201 1015 784 A1) Instead of an axial impeller, the impeller can also be designed as a radial impeller and / or a diagonal impeller.

From practice different techniques are known, for example, to secure an impeller on or on the rotor of an engine. Aluminum impellers can be manufactured or cast together with a rotor made of aluminum. It is disadvantageous that aluminum parts are basically expensive. In addition, they require a relatively high plastering effort and are inflexible in use, especially with respect to impellers. Namely, it can not realize different air conveying directions with identical components, namely due to the fixed assignment of the components. According to the desired / required air conveying direction thus two differently combined aluminum parts are kept. From practice, it is also already known to screw the made of aluminum or plastic impeller to the rotor of a motor. In this case, both directions of flow can be realized, depending on how the impeller is screwed. Compared to the aforementioned variant, the screwed-on impeller thus provides greater flexibility. In addition, when using a plastic impeller Verputzaufwand over the aluminum parts is greatly reduced and the plastic impeller can be made cheaper compared to the existing aluminum impeller. However, a significant disadvantage is the fact that the screwing of the impeller takes a relatively long time, thereby increasing the cost of assembly.

As a third variant, the impeller pressed onto the rotor is known, with the same flexibility as the screwed impeller, since both conveying directions can be realized with the same components. The assembly is compared to the screw variant simple and therefore inexpensive. In the realization of a pressing, a round plate made of steel is used for the secure connection between the impeller or the hub and the rotor, which is usually produced in a follow-on composite tool and inserted into the impeller tool before the injection-molding process.

Between the rotor and the impeller (for example, impeller) can form condensation, which is difficult to dissipate due to the given geometries. This applies in particular if there are no passages between the rotor and the pressed hub of the impeller. This Problem has already been recognized in the prior art and has introduced notches in the surface of the hub, but weaken the mechanical properties of the hub and on top of that cause high voltages in the pressed-up state of the hub.

Often, not least for reasons of cost, a rotor is used with a deep-drawn sheet steel housing whose surface is not machined. Regularly, the surface is provided with a powder coating. The deep drawing and the applied powder coating creates a large, to be bridged tolerance field. Accordingly, the circular disc used in the impeller must have a smaller inner diameter than the rotor, so that the connection holds securely even in the "worst case." In any case, a certain degree of certainty must be planned in. The difference in diameter to be bridged can be 0.6 to 0, for example , 8 mm.) Finite element method (FEM) calculations show that the expansion in diameter is transferred to the plastic hub, and if the circular disc and thus the hub are given a widening of, for example, 0.6 mm in diameter The above-mentioned problems have already been recognized in the prior art, for example in EP 1 609 996 B1, which already mentions that the cylindrically shaped steel blanks, as they are is used in known plastic impellers, is widened during the pressing process nnten prior art, the plastic hub rests with the blank over the entire surface of the rotor, a widening of the blank is forwarded to the hub, so that there may be disadvantageously high mechanical stresses in the hub, which may even cause a wheel break in some cases. Other disadvantages are that a drainage of condensation, which can form at dew point in the hub, is not possible. In addition, the plastic hub hinders the dissipation of heat through the rotor surface.

In order to remedy the disadvantages recognized in the state of the art, it is proposed according to EP 1 609 996 B1 to provide a segmented metallic blank. in which the different segments of the blank, to be understood in each case as a cylindrical part of the blank, have different inner diameters. In other words, the blank proposed in the prior art has uniformly distributed curved surface segments of lesser inner diameter along the circumference of the blank, so that the blank comes only with those segments for full contact with the surface of the rotor having the smaller inner diameter ,

However, the solution proposed in the prior art problem solution is equally disadvantageous because when pushing the impeller from the outset surface contacts exist and create only the recessed areas formed therebetween with a small radius "air." The Aufpressvorgang is still power consuming and tedious and there is a danger in that, due to the size of the segments intended for contacting, the blank in the pressed-on state bears against the surface of the rotor over the entire circumference, so that the same problem occurs as in the starting point there.

The present invention is based on the object, the generic arrangement of an impeller on an electric motor in such a way and further, that the problems occurring in the prior art are at least largely eliminated. It should be ensured a secure hold of the impeller on the rotor, the pressing of the impeller to the rotor should be easy and fast. When pressed impeller sufficiently cool air should be able to slide past the rotor and it should be guaranteed a condensate drain. It must also be ensured that the impeller sits securely on the rotor at all loads occurring during operation. Furthermore, a method for producing a corresponding arrangement is to be specified. The above object is solved by the features of claim 1. Thereafter, the generic arrangement is characterized in that the Ronde running polygonal or polygonal and with the formation of axial contact surfaces with the surface of the rotor on this, at least slightly deformed, is pressed. According to the invention it has been recognized that a simple and secure connection between the impeller and the rotor can be produced by incorporating a blank, when the blank is made multi-or polygonal. If the blank had the same inner diameter as the outer diameter of the rotor with an imaginary inscribed circle, the blank would make axial line contact with the surface of the rotor, with a number of lines corresponding to the number of surfaces existing between the corners each smallest inner diameter linear come to rest on the rotor surface. In a deformation of the Ronde when pushed onto the rotor, the line contacts to axially aligned surface contacts widen, with space between them to drain condensate and air circulation for the purpose of cooling remains. Basically, the Ronde may consist of any materials, provided that it ensures a sufficient mechanical strength in or on the hub of the impeller. It is also conceivable that the Ronde is generated in situ during the manufacture of the impeller or the impeller hub, for example, defined by a region of firmer material.

In a particularly advantageous manner, the Ronde is designed as a metal blank, which may in particular consist of sheet metal, preferably made of sheet steel. This ensures that the Ronde is designed sufficiently stable. As already stated above, the round blank is a polygonal or polygonal component. It should be noted at this point that, especially with regard to the state of the art, the term "round plate" is retained, although the teaching claimed here is not an ideally round component. The result is that between the eight corners there are eight surfaces with correspondingly eight contact lines or flared axial contact surfaces The number of corners to be preferred or even required depends essentially on the diameter of the rotor and From the required gap between the rotor and the Ronde off The octagonal design of Ronde is exemplified for a diameter in the range of 70 to 1 10 mm. For smaller diameters, the blank can be equipped with three corners, with larger diameters with 16 corners. Concretely, the sheet metal blank can be injected on the inside of the hub, in the passage of the hub, in the material of the hub. As part of the injection molding production of the impeller or the hub, the blank would have to be inserted into the injection-molded tool. It is also conceivable that the hub is at least partially encapsulated and firmly connected by the encapsulation with the impeller. It is not mandatory that the round blank is overmoulded. In the absence of a complete encapsulation gaps between the Ronde and the impeller hub arise. These gaps mean that there is no continuous contact between the blank and the hub even after the pressing and the deformation of the blank, and thus also no or only slight stresses are introduced into the hub or the impeller. The blank is advantageously encapsulated only at those locations where it undergoes little or no deformation.

The inner diameter of the blank or the circle inscribed in the polygonal roundel is smaller than the outer diameter of the rotor. By virtue of this measure, it is possible for the blank to be press-fit onto the rotor, with the surfaces between the corners being deformed during pressing to form the previously discussed contact surfaces. Specifically, the inner diameter of the Ronde may be selected such that when pushing the Ronde an initial axial line contact widens to an axial surface segment or surface contact. It is essential that in the corner areas a sufficient passage remains, on the one hand to ensure ventilation along the surface of the rotor and on the other hand, a drainage of condensation. After pressing and deforming the blank thus remain non-contact areas with respect to the surface of the rotor. The Ronde may have constructive measures that favor the pushing or pressing the impeller onto the rotor. For this purpose, it is advantageous if the Ronde in the edge region, at least on one side, a circumferential expansion, to facilitate pushing and pressing on the rotor. If a corresponding edge region is formed on both sides of the round plate, this favors the fact that the same impeller can be used for both air conveying directions, with the convenience of facilitated pushing on both sides. The inventive method solves the above-mentioned problem by the features of claim 10. The method relates to the production of an inventive arrangement according to the preceding embodiments.

First of all, a motor is provided, which is an electric motor, in particular an external rotor motor. This is preferably held vertically by a tool carrier, so that the assembly of the impeller or impeller takes place with fixed positioning of the motor.

Furthermore, an impeller or impeller is provided for mounting, wherein this impeller comprises a polygonal Ronde according to the inventive arrangement. The blank is incorporated in the passage of the impeller so that it serves for attachment to the rotor.

According to the desired conveying direction of the fluid, the impeller is positioned relative to the motor, so that the same impeller can be used for both conveying directions. Thereafter, the impeller is pushed onto the rotor and thereby pressed, under deformation of the Ronde, such that relative to the surface of the rotor axial, segment-like surface contacts with intermediate free passage areas for flow with fluids - air and / or water - arise.

According to the invention it is achieved that with reduced mechanical stresses, a sufficiently good connection between the surface of the rotor and the impeller is realized. Due to the resulting in the corners of the Ronde axial Passages can drain condensation water that arises when the dew point drops, without the hub being provided with the otherwise required indentations. The passages also serve for passing cooling air past the rotor surface, so that heat is dissipated.

There are now various possibilities for designing and developing the teaching of the present invention in an advantageous manner. For this purpose, on the one hand to the claims subordinate to claim 1 and on the other hand to refer to the following explanation of a preferred embodiment of the invention with reference to the drawings. In conjunction with the explanation of the preferred embodiment of the invention with reference to the drawing, generally preferred embodiments and developments of the teaching are explained. In the drawing show

1 is a schematic view of an embodiment of an inventive arrangement, in concrete an axial fan, in the assembled state,

2 shows the object from FIG. 1 in a schematic front view, FIG.

3 shows the object of FIGS. 1 and 2, partially in section, in a schematic side view,

Fig. 4 is a schematic view as shown in FIG. 1, the impeller of

Article from FIGS. 1 to 3, without rotor,

Fig. 5, the impeller of Fig. 4 in a view as shown in FIG. 3, but without

Rotor and

6 shows a schematic view of an exemplary embodiment of a sheet metal blank, corresponding to the equipment of the impeller according to FIGS. 1 to 5. Fig. 1 shows a schematic view of an inventive arrangement, comprising an electric motor 1 with rotor 2, wherein on the rotor 2, a hereafter referred to as impeller 3 impeller is pressed. A rotationally fixed connection between the hub 4 of the impeller 3 and the rotor 2 or its surface is produced by press fitting.

The wings 5 are equipped with aerodynamic features that play no role in relation to the teaching of the invention. At this point, it should be noted that the impeller 3 is pressed onto the rotor 2 in order to produce a specific flow direction. For the reverse flow direction, it is possible to press the impeller 3 the other way around the rotor 2, without changing the type and equipment of the impeller 3. Fig. 2 shows the object of Fig. 1 in a plan view, where there, between the hub 4 of the impeller 3 and the rotor 2, in a schematic view, the polygonal Ronde 6 can be seen, the surfaces of which have a contact against the surface of the rotor 2 which can be called expanded line contact. Ultimately, these are axially extending, segment-like contact surfaces, which are more or less pronounced depending on the deformation of the blank 6.

Fig. 3 shows the article of Figs. 1 and 2 in a schematic side view, partially in section. FIG. 3 clearly shows that the blank 6, designed as a sheet metal blank in the exemplary embodiment chosen here, is integrated in the material of the hub 4 of the impeller 3. The blank 6 is overmolded with the same material as the impeller, for example plastic.

FIG. 3 further shows, in a suggestive way, that the blank 6 has an extended region 7 on one side. Regardless, the impeller 3 is designed with the cast-Ronde 6 so that the impeller 3 can be pressed automatically for both conveying directions on the rotor 2. For both conveying directions, a single impeller is to be kept, which reduces the storage costs considerably. Maximum flexibility is given. Fig. 4 shows the impeller 3 of the arrangement of FIGS. 1 to 3, without rotor. The hub 4 of the impeller 3 is equipped inside with the Ronde 6, which is executed octagonal. 4, the flat surfaces 9 extending between the corners 8 of the blank 6 have a common smallest radius, formed by the respectively central point of contact of these surfaces 9 with an inscribed circle. This radius must be smaller than the outer diameter of the rotor 2 with respect to the surface of the rotor 2 in order to allow the hub 4 with the integrated blank 6 to be pressed onto the rotor, with deformation of the blank 6, more particularly between the corners 8 extending, originally flat surfaces. 9

With regard to the round blank 6, it should be noted that, in order to promote stability / strength, it can have any desired measures, such as embossing, beads, etc., without thereby leaving the teaching according to the invention.

FIG. 5 shows the object from FIG. 4 in a representation corresponding to FIG. 3, but without motor 1 / rotor 2. Here too, the integrated round plate 6 with its corners 8 and surfaces 9 can be seen.

Finally, FIG. 6 shows the blank 6 in isolated form, in this embodiment as an octagon with intermediate surfaces 9, which serve to bear against the rotor 2 and, when the hub 4 or the impeller 3 is pressed onto the rotor 2, for deformation , resulting in the mechanical support with appropriate voltage.

Fig. 6 further shows a circumferentially extended area 7, which facilitates the pushing and pressing on the rotor 2 in one direction. On the opposite side of the blank 6 discrete widenings 7 are provided in segmental design, which favor the pushing or pressing in the other direction. Each of the two edge regions can optionally have a peripheral expansion 7 or individual discrete widenings 7. With regard to further advantageous embodiments of the teaching of the invention reference is made to avoid repetition to the general part of the specification and to the appended claims. Finally, it should be expressly understood that the above-described embodiment of the teaching of the invention is only for the purpose of discussion of the claimed teaching, but does not limit the embodiment.

LIST OF REFERENCE NUMBERS

1 electric motor

2 rotor

3 impeller, impeller

4 hub, impeller hub

5 wings

6 plate

7 extended edge area (edge area of the blank), widening

8 corner of the round plate

9 flat surface of the round plate

Claims

1. Arrangement of an impeller on a rotating part, preferably on an electric motor (1), in particular on an external rotor motor, wherein the torque of the motor (1) on the impeller (3) by a rotationally fixed connection between the rotor (2) of the motor ( 1) and the impeller (3) or its impeller hub (4) is transmitted and wherein the connection via a press fit between the impeller hub (4) and the rotor (2), with the involvement of one of the impeller hub (4) preferably assigned, mechanical Tensioning Ronde (6) is realized,

That is, the blank (6) has a polygonal or polygonal shape and is pressed onto the surface of the rotor (2), at least slightly deformed, to form axial contact surfaces.

2. Arrangement according to claim 1, characterized in that the Ronde (6) in the manufacture of the impeller (3) or the impeller hub (4) is generated in situ.

3. Arrangement according to claim 1, characterized in that the Ronde (6) is designed as a metal blank, in particular made of sheet metal, preferably made of sheet steel.

4. Arrangement according to one of claims 1 to 3, characterized in that the Ronde (6) is designed as an octagon.

5. Arrangement according to one of claims 1 to 4, characterized in that the sheet metal blank on the inside of the hub (4), injected in the passage, in the material of the hub (4) or at least partially encapsulated.

6. Arrangement according to one of claims 1 to 5, characterized in that the inner diameter of the blank (inscribed circle) (6) is smaller than the outer diameter of the rotor (2).

7. Arrangement according to claim 6, characterized in that the inner diameter of the blank (6) is selected such that when pushing the blank (6) expands an initial axial line contact to an axial area segment.

8. Arrangement according to claim 6 or 7, characterized in that the inner diameter of the blank (6) is selected so that after the pressing and

Deformation of the blank (6) non-contact areas with respect to the surface of the rotor (2) remain.

9. Arrangement according to one of claims 1 to 8, characterized in that the Ronde (6) in the edge region (7), at least on one side, a zonal or segment-wise or circumferential widening to the pushing and pressing on the rotor ( 2) to facilitate.

10. A method for producing an arrangement according to one of claims 1 to 9, characterized by the following method steps:

Providing a motor (1), in particular an external rotor motor, preferably held vertically by a workpiece carrier;

Providing a wheel (3) with polygonal Ronde (6), integrated in the passage of the impeller (3);

Positioning of the impeller (3) corresponding to the desired conveying direction relative to the motor (1);

Pushing the impeller (3) onto the rotor (2) with deformation of the blank (6), such that opposite the surface of the rotor (2) axial, segment-like surface contacts arise with free passage areas lying between them.

1 1. A method according to claim 10, characterized in that in the manufacture of the impeller (3) a Ronde (6) is selected with an inner diameter which is such that when pressing the Ronde (6) an initial axial line contact an axial surface contact widens, such that after pressing and deformation of the Ronde (6) between the contact surfaces non-contact area with respect to the surface of the rotor (2) remain.