EP2898221A1

EP2898221A1 - Impeller having balance compensation

Info

Publication number: EP2898221A1
Application number: EP13745608.3A
Authority: EP
Inventors: Jürgen Moll; Christian Hammel
Original assignee: Ebm Papst Mulfingen GmbH and Co KG
Current assignee: Ebm Papst Mulfingen GmbH and Co KG
Priority date: 2012-09-18
Filing date: 2013-07-24
Publication date: 2015-07-29
Anticipated expiration: 2033-07-24
Also published as: US10018206B2; WO2014044441A1; CN104685221B; US20150233389A1; WO2014044441A4; CN104685221A; DE202012103554U1; EP2898221B1

Abstract

The invention relates to an impeller (1) for a fan, in particular an axial or radial fan having a hub (2) for connecting the impeller (1) to a drive motor and having fan blades (6) which are arranged circumferentially around the hub (2) and having pockets (9) in the hub region, having balance weights (15) which can be fastened therein, aligned in the axial direction. The balance weights (15) are made of U-shaped, bent weight clips made of spring-elastic material, having at least two opposite clip legs extending parallel to each other which are connected to each other via a bend section, and comprise a clamping gap between the clip legs. One of the clip legs extends within the pockets (9) and the other clip leg extends outside of the pockets (9), such that there is a clamping seat on a pocket wall (12) extending in the clamping gap.

Description

ebm-papst Mulfingen GmbH & Co. KG, Bachmühle 2, 74673 Mulfingen

"Impeller with balancing"

The present invention relates to an impeller for a fan, in particular an axial or radial fan, having a hub for connecting the impeller with a drive motor and fan blades, which are circumferentially arranged around the hub and with aligned in the hub region in the axial direction pockets with in these attachable balancing weights.

From DE 10 2006 057 087 a generic impeller is known. Here balancing weights formed in the pockets as plug-in weights are pressed or inserted. These plug weights are with a hammer, a

Hand lever or a press punched or pressed. For this purpose, it is necessary, the respective impeller from its mounting position in a

Take balancing machine out, whereby previously the impeller must be provided with a balancing mark in order to attach the balancing weight in the disassembled state.

From US-2008/0075596 A1 it is known to use U-shaped curved elastic balancers or clips as balancing weights, which are pushed in the radial direction onto a radially extending annular collar on the hub of the impeller. For this it is necessary to remove the impeller from the

To remove balancing machine after each measurement for attaching the weight, which is very laborious and time consuming. In addition, this allows No balancing in different axial planes on different radii.

From DE 10 2010 01 1 526.6 it is known, U-shaped curved forceps as balancing weights on the edges of the top or bottom plate by

Sliding in the radial direction to attach. In this type of attachment, there is the danger that at high rotational speeds, the balancing braces are thrown away by the centrifugal forces arising or move from their position. In addition, unwanted effects occur at high rotational speeds and the resulting high flow velocities

Flow noise due to the balancing weights in the air flow.

The same applies also for attached to the fan blades, as

Balancing weights trained balancers.

The present invention is based on the object, starting from a generic impeller to allow easy mounting of the balancing thread by hand directly in the balancing machine. This should be a positionally accurate and secure attachment of the balancing weights over the entire circumference of the impeller be possible and unwanted flow noise to be through

Balance weights are avoided.

According to the invention this is achieved in that the balancing weights are formed of U-shaped curved forceps made of resilient material, with at least two opposing clip legs which are interconnected via an arc section and between the clip legs include a nip, wherein one of the clip legs within the pockets and the other clip leg extends outside the pockets, so that a clamping fit is provided on a running in the nip pocket wall. Due to the embodiment of the invention is a positionally accurate setting of

Balancers on the impeller possible, and the balancers invention can not be thrown by centrifugal forces from the fan. moreover The balancers also produce no noise because they are not in the airflow of the fan. The embodiment of the invention allows a very easy joining by hand with a good grip of the balancing brackets in the respective balancing bag. To set the balancers according to the invention no resources such as hand presses, hammers or presses are necessary. In addition, the joining of the balancing brackets can be done in the balancing pockets in the mounted position in the balancing machine. As a result, when loading and unloading the fan from the balancing machine or in the balancing machine saves time and also so-called tandem balancing machines can be used. In addition, so-called double sensor techniques for finding the imbalance on the fan can be used by means of insertion aids. Also, it is no longer necessary

Provide balancing marks on the fan to achieve a precise balance.

Advantageous embodiments of the invention are contained in the subclaims and will be described with reference to the accompanying drawings

Embodiments explained in more detail. Show it:

Fig. 1 is a front perspective view of a radial fan

trained inventive impeller

2 shows a perspective rear view of the impeller according to FIG. 1

3 shows a section along the section line III-III in Fig. 2,

4 shows a view according to the detail according to IV in Fig. 1st

5 shows a section along the section line V-V in Fig. 4,

6 is a front perspective view of an inventive impeller, which is designed as axial fan, 7 shows the detail according to VII in Fig. 6,

8 is a rear view of the impeller of FIG. 6,

9 is a section along the section line IX-IX in Fig. 8,

10 is a side view of a first embodiment of a

balance clamp according to the invention,

1 1 is a perspective view of the balancing clamp of FIG. 10,

Fig. 12 is a side view of another embodiment of a

balance clamp according to the invention,

13 is a perspective view of the balancing clamp of FIG. 12,

Fig. 14 shows a further embodiment in side view of a

balance clamp according to the invention,

15 is a perspective view of the balancing bracket of FIG. 14 and

Fig. 16 shows a further embodiment of an inventive

Balancing clamp in perspective view.

In Figs. 1 to 16 the same parts or functionally identical parts are identified by the same reference numerals. If certain described and / or removable from the drawings features of the impeller or its components according to the invention are described only in connection with an embodiment, but these are also according to the invention, regardless of this embodiment as a single feature or in combination with Other features of the embodiment essential and claimed as belonging to the invention.

If in the present application is spoken by an axial direction, so it is a direction parallel to the axis of rotation and if it is spoken of a radial direction, this refers to a direction perpendicular to the axis of rotation.

In Fig. 1 is a front perspective view of an impeller 1 according to the invention, which is designed as a radial fan, shown. This impeller 1 has a hub 2, with which the impeller 1 with a rotor of an electric

Drive motor, in particular an external rotor motor is connected. For this purpose, the hub 2 has a circular cylindrical hub wall. Furthermore, the impeller 1 consists of a circular bottom disk 3 and one of these axially

opposite circular cover disk 4. Between these two

Discs 3, 4 extend paddles 6, which generate a flow of air through the impeller 1 upon rotation of the impeller 1 due to their design and arrangement.

The cover plate 4 has a circular inflow opening 7, in which the inflowing medium flows in the axial direction upon rotation of the impeller 1. As can be seen from Fig. 1, the cover disk wall has a concave arcuate course and has at its end a circular cylindrical, axially extending projection 8, which comprises the inflow opening 7. In its wall, the approach 8 axially extending, an interior having, unilaterally open pockets 9, which are circumferentially formed over the entire circumference of the neck 8. The pockets 9 have pocket openings 10 facing away from the bottom disk 3 and are partitioned off from one another by separating webs 11. The pockets 9 are bounded in the radial direction to the outside by an outer wall 12 and in the radial direction inwardly by an inner wall 13. Furthermore, the pockets 9 have an inner pocket bottom 14. These pockets 9 are expediently next to each other, formed over the entire circumference of the neck 8 and are advantageously the same size. These pockets 9 are used to hold balancing weights 15, which are designed as U-shaped curved balancing brackets, to which reference is made to FIGS. 10 to 16 described below. These balancing weights 15 designed as balancing clamps have at least two mutually opposite clamp legs 17, 18 which are connected to one another via an arc section 19, see for example FIGS. 10 to 13. These balancing clamps are made of resilient material, in particular of spring steel. When plugged in, the balancing clamps 15 are arranged such that one clip leg 17 extends within the respective pocket 9 and the other clip leg 18 extends outside the respective pocket 9, with a clamping fit on the outer wall 12 which is within one of the two clip legs 17, 18 formed clamping gap 21 extends. The balancing weights 15 designed as balancing clamps can easily be plugged axially. This can be done manually with little effort within the

Balancing machine done. Due to the over the entire circumference of 360 ° existing pockets 9 a very accurate balancing is possible. Furthermore, it is expedient according to the invention if an annular collar 23 is formed on the bottom disk 3 offset radially outwards relative to the hub 2 and extends in the axial direction away from the bottom disk 3. In its wall, the annular collar 23 pockets 24, which expediently over the entire

Ring collar circumference of 360 ° are arranged side by side. These pockets 24 suitably have the same size as the pockets 9 in the approach 8. The pockets 24 extend in the axial direction and have a

Pocket opening 25, which point away from the bottom plate 3. These pockets 24 also serve to accommodate the trained as balancing braces

Balancing weights 15. The pockets 24 also have dividing webs 26, one

Outer wall 27 and an inner wall 28. The radius of the annular collar 23 is smaller than the radius of the circular cylindrical projection 8, wherein the annular collar 23 and the projection 8 are arranged concentrically to each other, so that in this way two axially spaced, each radially extending balancing planes resulting in a very precise balancing of the invention

Impeller 1 is possible. The annular collar 23 may have a larger diameter than, or the same diameter as the projection 8, depending on the inclination of the bottom disk 3.

In FIGS. 6 to 9, an inventive designed as axial fan

Impeller 1 shown. This has a hub 31 which is formed as a hollow cylinder with a circular cross-section. At the outer periphery of the hub 31 fan blades 32 are arranged. This impeller 1, depending on the desired

Conveying direction in two different directions to be mounted on the engine. For this purpose, a hollow cylindrical inner hub 41 is integrally formed on an annular collar 35, with which the impeller 1 is mounted on a rotor of an electric motor, not shown. On both faces of the hub 31, the hub 31 in its wall over its entire circumference arranged side by side, in the axial direction

extending pockets 33, 36. These pockets 33, 36 are open on one side, with their pocket openings 34, 37 each extending in the axial direction. These pockets 33, 36 are used to hold as balancing braces

Balancing weights 15, the balancing weights 15, as to Figs. 1 to 5

described, correspond and are fastened in the same way. At its side opposite the pockets 33, the hub 31 has a collar 35 in its wall region. In this annular collar 35 over the entire circumference axially directed, one-sided open pockets 36 are formed. The pockets 33, 36 are all the same size and arranged side by side. Its pocket opening 34, 37 points in the axial direction X-X. The pockets 36 and the pockets 33 have

suitably the same dimensions and have an outer wall 38, an inner wall 39 and are separated from each other by dividers 40 from each other. The pockets 33 are offset relative to the pockets 36 offset radially outwards, so that the pockets 33 are at a greater radius than the pockets 36. This in turn result in two axially spaced, radially different sized balancing planes, which is a very accurate balancing of Allow impeller 1. Alternatively, it is also possible to attach the pockets 33, 36 on the same radius.

The inventive course of the pockets 9, 24, 33, 36, the

Balancing weights 15 are each axially fixed from the outside in the pockets 9, 24, 33, 36.

FIGS. 10 and 11 show a first embodiment of a balancing clamp 15a according to the invention, serving as balancing weights 15. This balance clamp 15a consists of two clip legs 17, 18, wherein the clip leg 17 is longer than the clip leg 18 and the two clip legs 17, 18 are connected to each other via an arc portion 19. It is provided according to the invention that, as shown in the preceding figure, the longer

Clip leg 17 within the pockets 9, 24, 33 and 36 extends. The width of the two clip legs 17, 18 is less than or equal to the width of the pocket openings of the pockets formed in the wheels 1. Between the clip legs 17, 18 a clamping gap 21 is formed. Formed on the longer clip leg 17 is a tongue 45 projecting from the clip leg surface in the direction of the bow section 19 and bent in the direction of the shorter clip leg 18, which has a cutting edge 46 at its free end. In the deferred state of the balancing clamp 15a prevents this tongue 45 that the balancing bracket 15a from the pockets 9, 24, 33 and 36 can be solved, since the tongue 45 presses with its cutting edge 46 due to the existing bias in the material of the outer wall. The balancing clamp 15a is a stamped and bent part.

In Figs. 12 and 13 is a further embodiment of an inventive

Balancing clamp 15b shown. This balance clamp 15b in turn consists of a longer clip leg 17 and a shorter clip leg 18, which are connected to one another via an arc section 19. These too

Balancing clamp 15b is advantageously produced as a stamped and bent part, and the Clip legs 17, 18 are designed such that they can be easily attached to the impeller 1 according to the invention with their legs. In this embodiment, the longer clip leg 17, which in the

plugged state within the pockets 9, 24, 33 and 36 extends, at its two longitudinal edges opposite each other from the

Staple leg surface in the direction of the arch portion 19 projecting serrated projections 47 which have an end cutting edge 48, with which they are in the mounted state of the balancing brackets 15b in the respective

Pocket wall can cut, whereby a release of the balancing brackets 15a is prevented. Again, between the two clip legs 17, 18 a clamping gap 21 is included.

FIGS. 14 and 15 show a further embodiment according to the invention of a balancing clamp 15 c according to the invention, which can serve as a balancing weight. Again, two clip legs 17, 18 are present, the clip leg 17 in turn has a greater length than the

Staple legs 18 which are interconnected via an arc portion 19. The clip legs 17, 18 each have at their ends an extension section 17a, 18a bent over in the direction of the arc section 19, wherein the extension section 18a is shorter than the extension section 17a. The two extension portions 17a, 18a are parallel to each other, and the extension portion 18a extends between the staple leg 17 and the staple leg 18, and the extension portion 17a extends on the side of the staple leg 17 facing away from the staple leg 18. By forming the extension portions 17a, 18a the weight of

Balancers 15c relative to the weight of the balancing brackets 15a, 15b increases, so that this balancing clamp 15c according to the invention is then used when a greater balancing weight is required. In Fig. 5, the arrangement of the balancing clamp 15 c is shown within a pocket. It can be seen that the balancing bracket 15c is supported with the extension portion 17a on the inner wall 13 of the pocket 9 and with the extension portion 18a on the outside of the outer wall 12 of the pocket 9. Der

Extension portion 17a, which extends within the pocket 9, is provided at the end with a bent away from the staple leg 17 bend 48, the end has a particular curved cutting edge 49, with which the extension portion 17a in the inner wall of the respective pocket

cuts, as well as the extension portion 18a with an end cutting edge 50 can cut into the outer wall of the respective pocket. The balancing bracket 15c is formed as a stamped and bent part, so that there is a very inexpensive production. The width of the clip legs 17, 18 and the extension portions 17a, 18a is such that they sit with little play within the respective pocket.

FIG. 16 shows a further embodiment according to the invention of a balancing clamp 15d according to the invention. This embodiment of balancing clamp 15d

differs from the previously described embodiments in that two parallel longer clip legs 17 are present. The distance between the two clip legs 17 is defined by a gap 51 which corresponds to the width of a separating web between the respective pockets. According to the embodiment in FIGS. 14 and 15, the clip legs 17 again have an extension section 17a, with a bending section 48. The shorter section

Clip leg 18, which extends outside the respective pockets, has a width which corresponds to the width of two adjacent pockets, and this clip leg 18 is connected via the bow portion 19 with the two mutually parallel clip legs 17. Due to this embodiment, the two extend parallel to each other

Clip leg 17 in the attached state in two adjacent pockets and the shorter clip leg 18 is located on the outer wall of the

Pockets on and covers this two adjacent pockets. This embodiment is used when particularly high balancing weights are desired and simplifies the attachment of the balancing braces 15d, since instead of two individual Balancers only a single balancing bracket 15d in can be attached to a Aufsteckvorgang. The shorter clip leg 18 in turn has an extension section 18a, as described in FIGS. 14 and 15.

The balancing clamps 15a, 15b, 15c, 15d shown in FIGS. 10 to 16, as already stated, are produced as stamped and bent parts, in particular from a resilient material such as spring steel or the like. This results in very favorable production costs. Furthermore, it is possible according to the invention, in the bottom 14 of the pockets 9, 24, 33, 36 form an opening for dissipating moisture.

The invention is not limited to the illustrated and described embodiments, but also includes all the same in the context of the invention embodiments. Furthermore, the invention has hitherto not been limited to the feature combinations defined in the claims, but may also be defined by any other combination of specific features of all individual features disclosed overall. This means that in principle virtually every individual feature of the independent claims can be omitted or replaced by at least one individual feature disclosed elsewhere in the application. In this respect, the claims are to be understood merely as a first formulation attempt for an invention.

LIST OF REFERENCE NUMBERS

1 impeller

2 hub

3 bottom plate

4 cover disc

6 fan blades

7 inflow opening

8 approach

9 pockets

10 pocket openings

1 1 partition

12 pocket wall

13 inner wall

14 pocket bottom

15 balance weights

15a balancing clamp

15b balancing clamp

15c balancing clamp

15d balancing clamp

17 clip legs

17a extension section

18 clip legs

18a extension section

19 arc section 21 nip

23 ring collar

24 pockets

25 pocket opening

26 partition

27 pocket wall Inner wall hub

Fan blades pockets

Pocket opening collar

Bags

Pocket opening pocket wall inner wall partition wall hub

tongue

Cutting edge extensions

Cutting edge Cutting edge Cutting edge Gap

Claims

claims

1. impeller (1) for a fan, in particular an axial or radial fan with a hub (2, 41) for connecting the impeller (1) with a drive motor and with fan blades (6, 32) circumferentially around the hub (2 , 41) are arranged around and with in the hub region in the axial direction aligned pockets (9, 24, 33, 36) fastened in this

Balance weights (15),

characterized in that the balancing weights (15) of U-shaped bent balancing brackets (15a, 15b, 15c, 15d) are formed of resilient material, with at least two mutually parallel, opposite bracket legs (17, 18), over a

Arc section (19) are interconnected, and between the

Clip legs (17, 18) include a nip (21), wherein one of the clip legs (17) within the pockets (9, 24, 33, 36) and the other clip legs (18) outside the pockets (9, 24, 33, 36 ) runs, so that a clamping fit on a in the clamping gap (21) extending

Pocket wall (12, 27, 38) is given.

2. impeller (1) according to claim 1,

characterized in that within the pockets (9, 24, 33, 36) extending staple leg (17) has at least one in the direction of the sheet portion (19) projecting cutting edge (46, 48).

3. impeller (1) according to claim 1 or 2,

characterized in that in the pockets (9, 24, 33, 36) extending clip legs (17) is longer than the outside of the pockets (9, 24, 33, 36) extending clip legs (18). Impeller (1) according to claim 2 or 3,

characterized in that centrally in the in the pocket (9, 24, 33, 36) extending clip legs (17) in the direction of the bow portion (19) and the shorter clip legs (18) bent tongue (45) is formed, the has a cutting edge (46) at its free end.

Impeller (1) according to claim 2 or 3,

characterized in that in the pocket (9, 24, 33, 36) extending clip legs (17) at its two longitudinal edges opposite in the direction of the arc section (19) projecting, serrated projections (47) having an end cutting edge (48) ,

Impeller (1) according to one of claims 1 to 3,

characterized in that the two clip legs (17, 18) at their free ends in each case in the direction of the curved portion (19) bent extension portion (17 a, 18 a) which is shorter than the associated clip legs (17, 18) and the

Extension portions (17a, 18a) parallel to each other.

Impeller (1) according to claim 6,

characterized in that the extension portion (17a) of the longer staple leg (17) extending in the pocket (9, 24, 33, 36) is bent so as to rest on the side of the staple leg (17) directed away from the shorter staple leg (18). 17) runs.

Impeller (1) according to claim 6 or 7,

characterized in that the extension portion (18a) of the shorter, outside the pocket (9, 24, 33, 36) extending

Staple leg (18) is bent so that it is the longer

Klammerschenkel (17) is facing.

9. impeller (1) according to any one of claims 6 to 8,

characterized in that the extension portion (17a) of the longer, in the pocket (9, 24, 33, 36) extending staple leg (17) has an end, of the staple leg (17) directed away bend (48) with at least one cutting edge (49 ) having.

10. impeller (1) according to any one of claims 1 to 9,

characterized in that the clip legs (17, 18) have a width which is smaller than / equal to the clear width of the pockets (9, 24, 33, 36).

1 1. impeller (1) according to one of claims 1 to 10,

characterized in that the shorter clip leg (18) extending outside the pockets (9, 24, 33, 36) has a width which corresponds to the width of two juxtaposed pockets (9, 24, 33, 36) and the shorter clip leg (18 ) is connected via an arcuate portion (19) to two adjoining clip legs (17) which are spaced by a longitudinal gap (51) corresponding to the width of the partition (11, 26) between the pockets (9, 24, 33, 36). 40), so that the two longer clip legs (17) each extend in separate, juxtaposed pockets (9, 24, 33, 36) in the plugged state.

12. impeller (1) according to any one of claims 1 to 1 1,

characterized in that in a formation as a radial fan, the blades (6) between a cover plate (4) and a bottom disc (3) extend, and the hub (2) on the bottom disc (3) is formed, wherein the pockets (9) on the one hand in an inlet (7) of the cover disc (4) surrounding approach (8) are formed and on the other hand in an axially of the cover plate (4) directed away, on the bottom plate (3) integrally formed annular collar (23), wherein the projection (8 ) and the annular collar (23) in Cross section are circular, and the diameter of the annular collar (23) is in particular less than or equal to the diameter of the

Approach (8).

13. impeller (1) according to any one of claims 1 to 12,

characterized in that in a design as Axiallüfterrad on a hollow cylindrical hub (31) radially projecting fan blades (32) are formed and on the one hand, the pockets (33, 36) in an end wall of the hub (31) formed front end and on the other hand in an opposite Run hub end formed annular collar (35) and wherein the diameter in the region of the end wall is greater than or equal to the diameter in the region of the pockets (36) of the annular collar (35).

14. impeller (1) according to claim 12 or 13,

characterized in that the pockets (9, 24, 33, 36)

Have insertion, which are aligned such that a

Insertion of the balancing weights (15) in the axial direction of the respective outer side of the impeller (1) is possible.

15. impeller (1) according to any one of claims 12 to 14,

characterized in that the pockets (9, 24, 33, 36) in their

Bottom portion (14) have openings for removing moisture.