EP3824190B1 - Ventilator and deflector plate for a ventilator - Google Patents

Description

The present invention relates to a fan, in particular an axial, radial or diagonal fan, with a fan impeller and a downstream guide device in the housing! flow channel, wherein the guide device comprises guide vanes.

Free-running diagonal or radial fans, especially those with backward-curved blades, are well known in practice. In such fans, there are no flow-carrying parts such as a spiral housing, guide vanes, diffusers or similar downstream of the impeller outlet. The flow exiting the impeller has high flow velocities. The dynamic pressures associated with these flow velocities are not used in free-running diagonal or radial fans. This means pressure and energy losses. As a result, such fans have too low pressure increases, too low air output and too low efficiency. In addition, these high flow velocities cause excessive noise emissions at the outlet. Furthermore, struts are often used to connect the motor fan wheel to a nozzle plate, which are usually very close to the impeller outlet. This creates an obstacle in the flow path and has an additional negative effect on air output, efficiency and acoustics. However, free-running diagonal or radial fans are often compact, i.e. they require little, often rather cuboid-shaped space in a higher-level system, and are inexpensive to manufacture.

Out of EP 2 792 885 A1 A radial fan is known in itself which has a round, bladed guide vane on the air outlet side for improved air circulation. This guide vane also serves as a suspension, but does not contribute to improving efficiency. The guide vane comprises a cover plate and a base plate, which each continue the corresponding cover plate or base plate of the impeller when assembled, as well as guide vanes which are partially arranged between the cover and base plate of the guide vane, but extend over their outer edges when viewed in the flow direction. The guide vane therefore causes a lot of noise. Another disadvantage of the known radial fan is that the guide device cover plate and the guide device base plate are not aligned when viewed in the flow direction. diverge greatly from each other, ie the flow cross-section widens significantly in the direction of flow. This leads to turbulence in the area of the guide device, increases the noise there and at the same time reduces the air output and thus the efficiency.

Furthermore, the US 5 848 526 A , WO 85/02889 A1 , US 2018/106267 A1 and CN 107 588 046 A each design of fans. In particular, the document US 2018/106267 A1 discloses an axial fan with a fan impeller and a downstream guide device in the housing/flow channel, wherein the guide device comprises guide vanes which, viewed in the spanwise direction or radial direction, extend only over a part of the housing/flow channel, wherein two flow regions are formed downstream of the impeller, of which the inner flow region closer to the axis is delimited in the spanwise direction by the hub ring of the guide device and by an outer ring of the guide device, and wherein the outer flow region further away from the axis is delimited in the spanwise direction by the outer ring of the guide device and by the wall of the housing.

The present invention is based on the task of designing and developing the generic fan in such a way that the problems occurring in the prior art are at least largely eliminated. While maintaining the lowest possible noise level, the static efficiency should be increased over a large area of the characteristic curve. In addition, the fan according to the invention should be different from competitive products.

Furthermore, an appropriate follow-up device should be specified.

The above object is achieved by the features of claim 1. According to this, in the generic fan, the guide device has a special structural design, namely the guide vanes, viewed in the span direction, extend only over a part of the flow area.

Apart from increasing the static efficiency or maintaining low noise levels, the compact design of the guide vanes, whose guide vanes essentially only extend over part of the span of the associated impeller, has a positive effect on tool and parts costs. Due to the comparatively smaller diameter of the guide vane in relation to a given impeller diameter, the tool size of the associated injection molding tools is smaller than usual.

This is especially true for axial fans.

In addition, appropriately designed radial fans are particularly suitable for installation in narrow ducts with axial flow continuation.

Due to a very detailed description of various embodiments of the claimed teaching with reference to the figures below, a general description of the teaching is omitted at this point, in particular with reference to the patent claims.

Fig. 1

in perspektivischer Ansicht, von der Abströmseite aus gesehen, eine Leiteinrichtung und ein Gehäuse eines Ausführungsbeispiels eines erfindungsgemäßen Ventilators axialer Bauart,

Fig. 2

in axialer Draufsicht, von der Abströmseite aus gesehen, die Leiteinrichtung und das Gehäuse aus Fig. 1,

Fig. 3

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse die Leiteinrichtung und das Gehäuse aus Fig. 1 und 2,

Fig. 3a

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse die Leiteinrichtung und das Gehäuse aus Fig. 1 bis 3 mit eingebautem Laufrad und schematisch dargestelltem Motor,

Fig. 4

in einer Seitenansicht und im Schnitt an einer Ebene parallel zur Achse die Leiteinrichtung und das Gehäuse gemäß Fig. 1 bis 3,

Fig. 5

in perspektivischer Ansicht, von der Zuströmseite aus gesehen, die Leiteinrichtung und das Gehäuse gemäß Fig. 1 bis 4,

Fig. 6

in axialer Draufsicht, von der Zuströmseite aus gesehen, die Leiteinrichtung und das Gehäuse gemäß Fig. 1 bis 5,

Fig. 7

in perspektivischer Ansicht, von der Abströmseite aus gesehen, eine Leiteinrichtung eines weiteren Ausführungsbeispiels eines Ventilators radialer oder diagonaler Bauart,

Fig. 8

in perspektivischer Ansicht, von der Abströmseite aus gesehen, die Leiteinrichtung gemäß Fig. 7 mit zugeordnetem Laufrad radialer Bauart,

Fig. 9

in axialer Draufsicht, von der Abströmseite aus gesehen, die Leiteinrichtung gemäß Fig. 7,

Fig. 10

in axialer Draufsicht, von der Abströmseite aus gesehen, die Leiteinrichtung und das Laufrad gemäß Fig. 8,

Fig. 11

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse die Leiteinrichtung und das Laufrad gemäß Fig. 8 und 10,

Fig. 12

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse die Leiteinrichtung und das Laufrad gemäß Fig. 8 und 10 eingebaut in ein druckseitiges Gehäuse mit dem Laufrad zugeordneter Einlaufdüse,

Fig. 12a

in axialer Draufsicht, von der Abströmseite aus gesehen, ein Gehäuse, eine Leiteinrichtung und ein Laufrad einer weiteren Ausführungsform eines Ventilators, wobei die Aufhängung dargestellt ist, in welche einige Leitelemente der Leiteinrichtung integriert sind,

Fig. 13

in perspektivischer Ansicht, von der Abströmseite aus gesehen, eine Leiteinrichtung und ein Gehäuse eines weiteren Ausführungsbeispiels eines axialer Bauart, das vom Wortlaut der Ansprüche nicht erfasst wird,

Fig. 14

in axialer Draufsicht, von der Zuströmseite aus gesehen, die Leiteinrichtung und das Gehäuse gemäß Fig. 13,

Fig. 15

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse die Leiteinrichtung und das Gehäuse gemäß Fig. 13 und 14,

Fig. 16

in axialer Draufsicht, von der Abströmseite aus gesehen, ein Gehäuse, eine Leiteinrichtung und ein Laufrad einer weiteren Ausführungsform eines Ventilators, bei dem die Leiteinrichtung aus Blech gefertigt ist,

Fig. 17

in einer Seitenansicht und im Schnitt an einer Ebene durch die Achse das Gehäuse, die Leiteinrichtung und das Laufrad gemäß Fig. 16,

Fig. 18

in axialer Draufsicht, von der Abströmseite aus gesehen, ein Gehäuse, eine Leiteinrichtung und ein Laufrad einer weiteren Ausführungsform eines Ventilators, bei dem die Leiteinrichtung aus Blech gefertigt ist und die Leitelemente einen angestellten Teil aufweisen.

There are now various possibilities for designing and developing the teaching of the present invention in an advantageous manner. For this purpose, reference is made on the one hand to the claims subordinate to claim 1 and on the other hand to the following explanation of preferred embodiments of a fan according to the invention with reference to the drawing. In connection with the explanation of the preferred embodiments of the invention with reference to the drawing, generally preferred embodiments and developments of the teaching are also explained. The drawing shows

Fig.1

in perspective view, seen from the downstream side, a guide device and a housing of an embodiment of an axial-type fan according to the invention,

Fig.2

in axial plan view, seen from the downstream side, the guide device and the housing made of Fig.1 ,

Fig.3

in a side view and in section on a plane through the axis the guide device and the housing Fig. 1 and 2 ,

Fig. 3a

in a side view and in section on a plane through the axis the guide device and the housing Fig. 1 to 3 with built-in impeller and schematically shown motor,

Fig.4

in a side view and in section on a plane parallel to the axis, the guide device and the housing according to Fig. 1 to 3 ,

Fig.5

in perspective view, seen from the inflow side, the guide device and the housing according to Fig. 1 to 4 ,

Fig.6

in axial plan view, seen from the inflow side, the guide device and the housing according to Fig. 1 to 5 ,

Fig.7

in perspective view, seen from the downstream side, a guide device of another embodiment of a fan of radial or diagonal design,

Fig.8

in perspective view, seen from the downstream side, the guide device according to Fig.7 with associated radial impeller,

Fig.9

in axial plan view, seen from the downstream side, the guide device according to Fig.7 ,

Fig.10

in axial plan view, seen from the downstream side, the guide device and the impeller according to Fig.8 ,

Fig. 11

in a side view and in section on a plane through the axis the guide device and the impeller according to Fig.8 and 10 ,

Fig. 12

in a side view and in section on a plane through the axis the guide device and the impeller according to Fig.8 and 10 installed in a pressure-side housing with an inlet nozzle assigned to the impeller,

Fig. 12a

in axial plan view, seen from the downstream side, a housing, a guide device and an impeller of a further embodiment of a fan, showing the suspension in which some guide elements of the guide device are integrated,

Fig. 13

in perspective view, seen from the downstream side, a guide device and a housing of a further embodiment of an axial design, which is not covered by the wording of the claims,

Fig. 14

in axial plan view, seen from the inflow side, the guide device and the housing according to Fig. 13 ,

Fig. 15

in a side view and in section on a plane through the axis, the guide device and the housing according to Fig. 13 and 14 ,

Fig. 16

in axial plan view, seen from the downstream side, a housing, a guide device and an impeller of a further embodiment of a fan in which the guide device is made of sheet metal,

Fig. 17

in a side view and in section on a plane through the axis the casing, the guide device and the impeller according to Fig. 16 ,

Fig. 18

in axial plan view, seen from the downstream side, a housing, a guide device and an impeller of a further embodiment of a fan, in which the guide device is made of sheet metal and the guide elements have an inclined part.

Fig.1 shows a perspective view of a guide device 1 serving as a guide device and a housing 2 of an embodiment of an axial-type fan according to the invention. The guide device 1 essentially consists of a hub ring 4, an outer ring 5 and guide vanes 3 extending between them. The guide device 1 is arranged, in the assembled state of the fan according to the invention, downstream of an impeller (not shown) within a housing 2, so that an air duct (outer flow area) 6 is created between the guide device 1 or its outer ring 5 and the wall of the housing 2, through which part of the air flowing off the impeller is guided. Another part of the air flowing off the impeller is guided through the inner flow area 7, which, viewed in the span direction, is delimited by the hub ring 4 towards the axis, and which, viewed in the span direction, is delimited by the outer ring 5 towards the outer flow area 6. The inner flow area 7 is interspersed with guide vanes/guide elements 3 (in the example 13, preferably 3-19) which stabilize the swirling flow near the axis emerging from the impeller by reducing the swirl in the flow. This increases the efficiency. The hub ring 4 and the outer ring 5 run essentially over the entire circumference around the axis. The hub ring 4 surrounds an inner receiving area 8 in which, for example, the drive motor of the fan can be arranged. The receiving area 8 is not flowed through or advantageously only has a small air volume flow through it (0.1%-2% of the total air volume flow) in order to be able to transport away the waste heat produced by the motor.

The outer flow area 6 has essentially no additional guide elements at least over a large area, seen in the span direction. As a result, little or no additional noise is caused in this area as a result of the interaction of the flow emerging from the impeller and the guide elements. This leads to a significantly reduced noise level in operation, since the flow speeds are high in this outer area 6 in particular. Flow stabilization in the outer flow area 6 by guide elements is not crucial for the efficiency of the fan. Overall, a fan is obtained that is low-noise, namely because guide elements are essentially missing in the outer flow area 6 or there are only a few guide elements there compared to the inner flow area 7. In addition, the fan according to the invention has a high efficiency due to the flow stabilization by the guide elements 3 in the inner flow area 7.

Fig.2 shows, in axial plan view and seen from the downstream side, the guide device 1 and the housing 2 according to Fig.1 The outer flow area 6, which in the exemplary embodiment has no guide elements, and the inner flow area 7 with the guide elements 3 can be clearly seen. In this illustration, no connection between the guide device 1 and the housing 2 is shown. In practice, however, such a connection is necessary in order to attach the guide device 1 to the housing 2. It can be realized using flat or rod material made of metal, or also using elements designed for optimal flow, which connect the guide device 1 to the housing 2. Such a necessary suspension, which must also run through the outer flow area 6, is not to be regarded as an actual guide element and does not change the statement that the outer flow area 6 essentially has no further guide elements.

In the exemplary embodiment, both the wall of the housing 2 and the hub ring 4 have a conical design towards the outflow end. An outer diffuser 10 is thus integrated in the housing 2. Both the inner flow area 7 and the outer flow area 6 are thus designed as diffusers with an expanding flow cross-section towards their outflow end. This is very advantageous for the static efficiency, especially in the case of axial fans. The outer ring 5 of the guide device 1 in the exemplary embodiment is designed in the shape of a cylinder jacket, aligned in the axial direction. This is particularly advantageous if the guide device is manufactured as a cast part, since the demolding of the guide elements 3, which are connected to the outer ring 5 at their outer end 12, is then greatly simplified. It is also conceivable to design a hub ring 4, to which the guide elements 3 are connected at their inner end 11, in the shape of a cylinder jacket for the same reason.

On a housing 2 and/or a guide device 1, fastening provisions, for example fastening flanges, can advantageously be integrated or attached on both the inflow and outflow sides, which can serve to attach the fan to a higher-level system, for example an air-conditioning system.

Fig.3 shows, in a side view and in section on a plane through the axis, the guide device 1 and the housing 2 of Fig. 1 and 2 . The cross-section shows the outer flow area 6 without guide elements, the inner flow area 7 with the guide elements 3 and the receiving area 8 within the hub ring 4. The impeller (not shown) is arranged in the assembled state in area 29 upstream of the guide device 1. When the fan is in operation, the air flows approximately from left to right in this view, first through the inlet nozzle 9 integrated in the housing 2, then through the impeller (not shown) before it is divided into the outer flow area 6 and the inner flow area 7, in which the flow is stabilized (especially in the inner flow area 7) and in which kinetic energy of the flow is converted into pressure energy. In the area of the receiving area 8 within the hub ring 4 there is a provision or mechanism 18 for attaching a motor.

There are basically two different support concepts for the motor with the impeller. On the one hand, the guide device 1 can be designed to be load-bearing. This means that it is stably connected to the housing in the area of its outer ring 5 (with struts, flat material or aerodynamically optimized sheet metal or plastic elements) and the motor together with the impeller is held on a motor fastening device 18 in the inner area 8 of the guide device 1. On the other hand, the guide device 1 can be designed to be non-load-bearing, which means that the motor is fastened to a housing 2 via a support device (in particular consisting of rod or flat material), and a non-load-bearing guide device 1 is then fastened to the motor or the associated support device, or fastened to the housing 2 by means of a separate support device. In all cases, parts of the support device must traverse the outer flow area 6, which should not change the statement that the outer flow area 6 is essentially free of guide elements over a large part of its span.

The guide elements 3 in the embodiment have a special and advantageous design. In the area of the inflow, they consist of an inclined part 16 adapted to the inflow direction, and in the area of the outflow, an axially aligned part 15 and a transition area 17 located between the parts 15 and 16. Here, the transition area 17 is simply designed as a kink. An inflow that is as shock-free as possible in the area of the leading edge 13 of a guide vane 3 is advantageous for achieving a high level of efficiency and low noise generation. The inclined part 16 of the guide vane 3 serves this purpose, which is aligned approximately parallel to the direction of the swirling inflow coming from the impeller (see also Fig.4 ). In conjunction with the conical hub ring 4, however, the demolding of a guide vane that is set, i.e. not aligned in the axial direction, would be very difficult due to undercuts. For this reason, part 15 of the guide vanes 3, which is located in areas of the conical hub ring, is designed as an axially aligned part. This is also the case in Fig.2 This can be clearly seen in areas where the inner end 11 of a guide element 3 borders on the conical part of the hub ring 4. Thus, the hub ring 4 and guide elements 3 together with the outer ring 5 can be demolded parallel to the axial direction without undercuts, if the guide device 1 is a cast part, preferably made by plastic injection molding. For undercut-free demolding of a one-piece guide device 1 from a casting tool, it is advantageous if, as in the illustrated embodiment, the hub ring 4 in the area of the inclined part 16 of the guide vane 3 is not conical, but rather cylindrical in shape. In the embodiment, the hub ring 4 is therefore more cylindrical in shape in a first area and more conical in a second area.

Fig. 3a shows in a side view and in section on a plane through the axis the guide device 1 and the housing 2 of Fig. 1 to 3 with built-in impeller 19 of axial design and the schematically shown motor 34, which consists in particular of a rotor 35 and a stator 36. The impeller consists of a hub ring 38, to which advantageously 3-13 impeller blades 22 are attached. The impeller 19 runs inside the housing 2 so that there is only a small gap between the impeller blades 22 and the housing 2. The impeller 19 is attached at its hub ring 38 to the rotor 35 of the motor 34, which drives the impeller 19. The guide device 1 is attached to the stator 36 of the motor 34. In load-bearing embodiments, the guide device 1 is firmly connected to the housing 2 at its outer ring 5 by means of suspension elements (not shown); in non-load-bearing embodiments, the motor 34 is firmly connected to the housing 2 at its stator 36 by means of suspension elements (not shown).

The outer contour of the impeller hub 38 advantageously has the same or a similar outer diameter as the outer contour of the hub ring 4 of the guide device 1, at least at the mutually facing ends. This provides an essentially continuous flow-limiting contour towards the inner area close to the axis, which is very advantageous for high efficiency and low noise generation. Furthermore, in the exemplary embodiment, a hub cap 37 is attached to the inflow side of the hub ring 38 of the impeller 19, which can, for example, have approximately the outer contour of half an ellipsoid, and which forms a continuous, inner flow-limiting contour with the hub ring 38.

In the embodiment, the motor 34 is an external rotor motor which is mounted within the hub rings 38 and 4 (or also in the receiving area 8 within the hub ring 4), which means a space-saving solution and enables a compact design of the fan.

Advantageously, a slight air volume flow is generated within the hub rings 38 and 4 (or also in the receiving area 8 within the hub ring 4) by suitable measures (openings, bores, slots or similar) in order to be able to better dissipate the waste heat of the motor 34.

Fig.4 shows, in a side view and in section on a plane parallel to the axis, the guide device 1 and the housing 2 according to Fig. 1 to 3 The cutting plane does not pass through the axis, but is at a distance from it that is in the area of the mean radius of a guide vane 3. As a result, some guide vanes 3 appear to be cut, and their already Fig.3 The structure described is even clearer. The guide vanes 3 have an inflow edge 13 on the inflow side and a corresponding outflow edge 14 on the outflow side. The inclined part 16 of a guide vane 3 is aligned approximately parallel to the flow direction of the swirling flow arriving from the impeller, particularly in the area of the inflow edge 13. An axially aligned part 15 of the guide vane is formed towards the outflow edge 14. This design significantly facilitates the demolding of a guide device 1 with a conical hub ring 4 and/or conical outer ring 5 from a casting tool. The transition 17 between the parts 15 and 16 of a guide vane 3 is designed as a kink in the exemplary embodiment, but can also be designed, for example, as a rounded area with a continuous tangent or a continuous curvature. The angle that the inclined part 16 of a guide wing 3 has approximately at the inflow edge 13 to a parallel to the axis is advantageously in a range between 20° and 50°. The inclined part 16 of a guide wing 3, as in the embodiment, advantageously has the profile of an airfoil in cross section.

Fig.5 shows, in perspective view from the inflow side, the guide device 1 and the housing 2 according to Fig. 1 to 4 . During operation, the air flows through the inlet nozzle 9 into the housing 2. From its inflow edge, the flow channel delimited by the wall of the housing 2 or the nozzle 9 tapers in the area of the nozzle 9 to a narrowest cross-section when air flows through, whereby the air is accelerated. Approximately at the level of a narrowest An impeller is arranged in the cross-section of the housing 2. The embodiment is particularly suitable for an impeller of axial design. Within the hub ring 4, in Fig.5 a mounting flange 18 with holes for attaching a motor is clearly visible.

The guide device 1 is advantageously manufactured in one piece using a plastic injection molding process. In comparison to known guide wheels, which extend to the outer contour of the housing 2, a significantly smaller injection molding tool is required, which saves tool costs and production costs due to the smaller outer diameter of the guide device 1. The housing 2 itself, including the integrated inlet nozzle 9 and integrated outer diffuser 10, can advantageously be manufactured inexpensively from sheet metal. In this case, production from one or more sheet metal parts is conceivable, which are then screwed, welded, riveted or otherwise connected.

In Fig.6 is, in axial plan view, seen from the inflow side, the guide device and the housing according to Fig. 1 to 5 shown. The outer flow area 6 and the inner flow area 7 can be clearly seen, which are separated from each other by the outer ring 5 of the guide device 1. The outer ring 5 is axially aligned. The mounting flange 18 for mounting a motor is arranged in the receiving area 8. In this illustration, only the inclined part 16 of the guide vanes 3 up to the transition area 17 can be seen in this embodiment.

In the embodiment shown, the guide vanes 3 are designed in a sickle shape, i.e. in this view, the inflow edges 13 of the guide vanes 7 are curved. The ends of the inflow edges 13 located on the outer ring 5 are offset in the circumferential direction against the direction of rotation of the impeller compared to the ends of the inflow edges 13 located on the hub ring 4. In this case, the direction of rotation of the impeller (not shown) is clockwise with respect to the given viewing orientation.

Fig.7 shows, in perspective view, seen from the downstream side, a guide device 1 of a further embodiment of a fan of radial or diagonal design. The guide device 1 has 4 guide elements 3, which extend radially in a curved course from a hub ring 4 to an outer ring 5. A fastening flange 18 for fastening a motor is attached within the hub ring 4. In the exemplary embodiment, the guide elements 3 are designed to be aligned in the axial direction and can advantageously be made of sheet metal. The outer ring 5 in the exemplary embodiment has the geometry of a rotating body around the axis.

Fig.8 shows, in perspective view, seen from the downstream side, the guide device 1 according to Fig.7 with associated impeller 19 of radial design. The radial impeller 19 in the exemplary embodiment consists essentially of a cover disk 20, a base disk 21 and blades 22 extending between them. The motor is not shown. It can be attached on the stator side to the fastening flange 18 within the hub ring 4 of the guide device and on the rotor side to the corresponding fastening device 30 on the impeller 19. The guide device 1 is arranged downstream of the flow outlet 31 from the radial impeller 19, but does not extend over the entire span at the flow outlet 31 from the impeller 19, only over an area closer to the base disk 21. The contour of the outer ring 5 of the guide device 1 in the exemplary embodiment causes the air emerging radially from the radial impeller 19 to be deflected more in the axial direction, in a direction parallel to the axis.

Fig.9 shows, in axial plan view from the downstream side, the guide device according to Fig.7 . In this illustration it can be clearly seen that the guide elements 3, of which only the trailing edge 14 can be seen, are aligned in the axial direction. A fastening device 18 is attached in the receiving area 8 inside the hub ring 4. The guide elements 3 are curved in the viewing plane, with the curvature starting from the inside of the hub ring 4 outwards to the outer ring 5 running against the direction of rotation of an impeller. The direction of rotation of an impeller in the embodiment shown in this illustration is clockwise. The angle of inclination of the guide elements 3 to the corresponding radial direction advantageously has the maximum value on the outer ring 5, which is greater than 20°, advantageously greater than 35°.

Fig.10 shows, in axial plan view from the downstream side, the guide device 1 and the impeller 19 according to Fig.8 . For the design of the guidance system 1, Fig.9 The outer edge 24 of the base disk 21 of the impeller 19 has a smaller outer diameter than the inflow-side edge 23 of the outer ring 5 of the guide device 1. This makes it possible to slide the guide device 1 over the base disk 21 of the impeller to facilitate assembly of the fan. In the illustration, between the outer edge 24 of the base disk 21 of the impeller 19 and the inflow-side edge 23 of the outer ring 5 of the guide device 1, parts of the blades 22 can be seen, which, viewed at their trailing edge or their course towards the cover disk 20, can be located radially further out than the outer edge 24 of the base disk 21. The direction of rotation of the impeller 19 is clockwise.

Fig. 11 shows, in a side view and in section on a plane through the axle, the guide device 1 and the impeller 19 according to Fig.8 and 10 . In section, the contour of the outer ring 5 of the guide device 1, which is connected to the radially outer ends 12 of the guide elements 3, can be clearly seen. This is strongly curved towards its inflow end 23, so that at the inflow end 23 of the outer ring 5 it has no or only a small angle of attack compared to the flow, which flows out of the impeller 19 in a more radial direction. As it runs, it deflects this flow in an axial direction. At the downstream edge 28, it therefore runs approximately parallel to the axis. The outer ring 5 alone (without guide elements 3) according to this embodiment can be demolded from a casting tool without undercuts. The guide elements 3, which in the embodiment are advantageously made of sheet metal, can then be attached to the outer ring 5 of the guide device 1, for example by screwing or clipping. The guide device 1 with the outer ring 5 extends, viewed in the span direction of the impeller 19, only over a part of the flow outlet 31 from the impeller 19. With regard to the outlet width of the impeller 19 (= width measured in the axial direction of the outlet 31 from the impeller 19, viewed in axial section from the cover disk 20 to the base disk 21), the inflow-side edge 23 of the outer ring 5 of the guide device 1 is located approximately at an axial position in the range of 50%-70% of the width measured from the cover disk 20. The guide elements 3 in the embodiment have rather small axial

The axial extension of the guide elements 3 is approximately 20%-60% of the axial width of the outlet 31 of the impeller 19, thereby achieving an axially compact design.

Fig. 12 shows, in a side view and in section on a plane through the axle, the guide device 1 and the impeller 19 according to Fig.8 and 10 to 11 , with an inlet nozzle 9 built into a housing 2 which is designed as a pressure-side air duct. In this housing 2 the air is guided further after the impeller 19 in a direction approximately parallel to the axis. The guide device 1 shown can be used particularly advantageously in this configuration. The air exiting the impeller 19 at the outlet 31 is divided into two flow areas, firstly the outer flow area 6 and the other hand the inner flow area 7. The outer ring 5 of the guide device 1 represents the separation between the two flow areas 6 and 7. The outer flow area 6 has essentially no further guide elements over a large part of its span. The inner flow area 5, on the other hand, has the guide elements 3, 4 in the exemplary embodiment, which stabilize the swirling air flow exiting the impeller 19 in the flow area 7 closer to the axis by reducing the swirl. A particularly significant increase in efficiency can be achieved if the side walls of the housing 2 are located relatively close to the outlet 31 from the impeller 19, in particular if the channel width (= the width of the housing 2, seen in section and in the radial direction, at the level of the outlet 31) is at least partially less than 1.6 times the largest diameter of the impeller 19, which is often the case due to the compact design of such housings 2.

The guide device 1 must be attached to the housing 2 by a suspension (not shown). This can advantageously be achieved by extending one, several or all of the guide elements 3 to the wall of the housing 2.

Fig. 12a shows, in axial plan view from the downstream side, a housing 2, a guide device 1 and an impeller 19 of another embodiment of a fan. The outer edge 24 of the base plate 21 of the impeller 19 lies within the inflow-side edge 23 of the outer ring 5 of the guide device 1. This allows the guide device 1 to be pushed over the base plate 21. In contrast to embodiments according to. Fig.7-12 the guide elements 3 are not curved. This significantly simplifies the manufacture of the guide elements 3 from sheet metal. In order to achieve good flow properties, high efficiency and low noise levels, the guide elements 3 are twisted or angled relative to the radial direction. In the radial area of the inflow end 23 of the outer ring 5, the angle of twist to the local radial is approximately 30°, advantageously 15°-45°. At the inner end 11, the guide elements 3 in the exemplary embodiment meet the hub ring 4 at an acute angle. The hub ring 4 and the guide elements 3 are advantageously made from sheet metal and welded and screwed together. Due to its contour, the outer ring 5 is designed as a rotational body (similar to the outer ring according to. Fig.7-12 ) is advantageously manufactured as a cast part, in particular as a plastic injection-molded part. The connection of the guide elements 3 at their outer end 12 to the outer ring 5 is advantageously carried out by clipping, screwing, riveting or the like. Appropriate provisions can be present on the injection-molded part.

The suspension of the guide device 1 and thus also of the motor and the impeller 19 on the housing 2 is carried out by means of the suspension 32, in which the function of some guide elements is integrated. The geometry of the suspension 32 radially inside the outer ring 5 of the guide device 1 corresponds approximately to the geometry of the other guide elements 3. The suspension 32 is advantageously made of sheet metal and is attached to the housing 2 with the fastening 33, advantageously by screws or rivets. This functional integration leads to particularly cost-effective production. The suspension 32 with the integrated guide element function also traverses the outer flow area 6. Since additional guide elements 3 are present in the inner flow area 7, the embodiment also applies that the outer flow area 6 has essentially no guide elements, at least in comparison to the inner flow area 7. Advantageously, at most half the number of suspension-specific elements run in an outer flow area 6. This is little compared to the inner flow area 7, since the outer flow area 6 additionally has a much larger cross-sectional area than the inner flow area 7 and thus the distance between adjacent suspensions 32, seen in the circumferential direction, is large compared to the distance between adjacent guide elements 3 in the inner flow area 7, taking into account the integrated suspensions / guide elements 32.

Fig. 13 shows, in perspective view from the downstream side, a guide device 1 and a housing 2 of another embodiment of an axial-type fan. Suspension struts 25 are shown schematically, which in this load-bearing embodiment of the guide device 1 provide the connection between the guide device 1 and the housing 2. The suspension struts 25 can be made of sheet metal, rod material or cast iron, and can then advantageously be provided with a shape that is optimized for aerodynamics. In the case of suspension struts 25 made of flat material, it is also conceivable that they are not axially aligned, but are attached at an angle to the axial direction that is favorable for aerodynamics. Despite the presence of the suspension struts 25, the outer flow area 6, at least in comparison to the inner flow area 7, is to be regarded as essentially free of guide elements. The suspension struts 25 can be screwed, riveted, welded or the like to the housing 2 and/or outer ring 5 of the guide device 1. A one-piece, monolithic, integral production of the entirety of the housing 2 and the guide device 1 with suspension struts 25 as a cast part is also conceivable.

Similar to the embodiment according to. Fig. 1-6 the guide vanes 3 have an inflow-side inclined part 16, an outflow-side axially aligned part 15 and a transition region 17 in order to combine the realization of flow-optimized inflow angles with easy demoldability of the guide device 1, in particular if the hub ring 4 and/or outer ring 5 of the guide device 1 have a conical shape at least in some areas. The transition region 17 is designed here as a rounded region that connects the inclined part 16 and the axially aligned part 15 in a tangentially continuous manner.

Fig. 14 shows, in axial plan view from the inflow side, the guide device 1 and the housing 2 according to Fig. 13 . The guide device 1 has 11 guide elements 3. The 4 suspension struts 25 are arranged slightly unevenly distributed over the circumference, since in their circumferential position they are always arranged approximately between adjacent guide elements 3. In contrast to the Fig. 1-12 and 12a In the embodiments shown, the outer ring 5 of the guide device 1 is not designed as a rotating body. However, it still runs over the entire circumference and connects the guide elements 3 to one another at their outer end 12. The outer ring 5 is not designed to be axially aligned, but is essentially conical with specially designed demolding areas 26 near the guide vanes 3, which have the function of enabling or facilitating the demolding of the guide device 3 from a casting tool. In fact, in the demolding areas 26, in which it is necessary for a clear demolding in the axial direction, the outer ring 5 is designed to be locally axially aligned.

Between the axially aligned areas 26 and the conical areas 27 of the outer ring 5, tangent-continuous transition areas are formed in an area between adjacent guide vanes 3, and step-like transition areas are formed in the area of the guide vanes 3, with the shape of the steps there corresponding approximately to the continuation of the contour of the guide vanes 3. In other words, an area of the guide vanes 3 near their outer end 12 connects an axially aligned part 26 of the outer ring 5 with a conical part 27 of the outer ring 5. Due to the special, Fig. 13 The design of the guide elements with an inclined part 16 and an axially aligned part 15, as already described, ensures that the circumferential extension of a guide vane 3, in particular near the outer end 12, is very low. This minimizes the circumferential area in which the outer ring 5 has to be designed in the form of a demolding area 26 in the shape of a cylinder jacket in order to achieve demolding without undercuts, which is advantageous in particular for the efficiency.

In Fig. 14 the outer flow area 6 with few guide elements and the inner flow area 7 with many guide elements can be clearly seen. The area inside the hub ring 4 is not shown in detail here, but can be similar to the embodiments according to Fig. 1-12 , 12a be designed.

Fig. 15 shows, in a side view and in section on a plane through the axis, the guide device 1 and the housing 2 according to Fig. 13 and 14 One can clearly see the at least partially conical design of the outer ring 5 of the Guide device 1. In the embodiment shown, this outer ring 5 is designed in such a way that the radius (distance from the axis) of the contour decreases in the flow direction. In contrast, the hub ring 4 is designed to be axially aligned with a cylindrical shell shape. The cross section of the inner flow area 7, limited towards the axis by the hub ring 4 and towards the outer flow area 6 limited by the outer ring 5, tapers in the flow direction from left to right (in the illustration shown). The inner flow area 7 is thus designed as a confuser. This design leads to additional stabilization of the swirling flow near the axis flowing out of the impeller (not shown), thereby achieving a further increase in efficiency. Furthermore, a particularly advantageous long-throw behavior of the air exiting from the flow areas 6 and 7 on the outflow side is achieved, i.e. the air jet remains compact over a long distance and has high air velocities over a long distance in the area of the imaginary continuation of the axis, which is advantageous for some applications of a fan.

The type of conical design of the outer ring 5 of the guide device 1 also influences the cross-sectional profile of the outer flow area 6. This flow area 6 therefore takes on the character of a diffuser to a greater extent. In order to obtain an optimal cross-sectional expansion of the flow area 6, the conical opening angle of the outer diffuser wall 10 integrated in the housing 2 must therefore be selected to be smaller than in the case of a cylinder jacket-like design of the outer ring 5. This makes the outer diameter at the downstream outlet from the housing 10 lower, which enables a more compact design. If necessary, with such a conical design of the inner ring 5, the formation of the diffuser 10 on the housing 2 can even be dispensed with, i.e. the housing 2 can be designed with an axially aligned cylinder jacket contour towards its outflow end, which simplifies the manufacture of the housing 2.

In section, the structure of the guide vanes 3, consisting of the inclined part 16, the axially aligned part 15 and the tangent-continuous transition area 17, can be clearly seen. Since the suspension struts 25, which are axially aligned in the embodiment, are unevenly distributed over the circumference, only the upper strut 25 is cut; the others are not visible. In Fig. 15 the receiving area 8 within the hub ring 4 is shown with a fastening device 18 for a motor of the fan.

In Fig. 16 is shown in an axial plan view, seen from the downstream side, of a housing 2, a guide device 1 and an impeller 19 of a further embodiment of a fan. In this embodiment, the guide device 1 is made essentially of sheet metal and is therefore advantageously constructed essentially from flat partial areas. In particular, there are no flat areas which have a significant curvature. The impeller 19 shown, of which the base plate 21, cover plate 20 and the blades 19 can be partially seen, is a radial impeller. The housing 2 is a flow channel with a square cross-section in which the air is passed on in the axial direction, in the view towards the viewer, after exiting the impeller 19 or the guide device 1. The outer contour of the guide element 1 or its outer ring 5 also has a square contour in this direction of view. It is rotationally symmetrical with a division into four, but here it is not a rotating body. This makes it easier to construct the guide element 1 from flat areas, which makes it much easier to manufacture the guide element 1 from sheet metal. In addition, a square outer contour of the guide element 1 is particularly suitable in terms of flow technology if the housing 2 also has a square cross-section. As a result, the outer flow area 6 has a largely constant width, defined by the distance between the outer ring 5 of the guide device 1 and the wall of the housing 2, which form the inner and outer edges of the outer flow area 6.

The inner flow area 7, which is limited radially inwards by the hub ring 4 and radially outwards by the outer ring 5, is penetrated by the guide elements 3. These are also designed as flat parts in accordance with the simple manufacture in sheet metal. In the example, they are designed as axially aligned parts 15, i.e. parallel to the fan axis. The hub ring 4 also has the aerodynamically advantageous square contour parallel to the contour of the housing 2 or the contour of the outer ring 5. A fastening area 18 for the stator side of a motor (not shown) is provided on the hub ring 4. A fastening device 30 for the rotor side of the motor can be seen on the base plate 21 of the impeller 19.

The outer ring 5 is also essentially made up of flat areas 5a, 5b, 5c. The flat area 5c, which runs perpendicular to the fan axis, is assigned to the circular inflow-side edge 23. This provides a favorable inflow angle compared to the flow exiting the impeller 19 in an approximately radial direction. The flat areas 5a, which lie parallel to the fan axis in the design area and thus parallel to the air conveying direction in the housing or flow channel 2, are assigned to the outflow-side edge 28. Flat transition areas 5b are also formed between the flat areas 5c and 5a, which promote the low-loss deflection of the air exiting radially from the impeller 19 in the axial direction.

The outer side length of the guide device 1 in this embodiment is, as seen in this view, approximately 1.15 times the outer diameter at the outer edge 24 of the base plate 21 of the impeller 19, advantageously it is 1.1-1.2 times. Such a ratio is particularly suitable for tight installation conditions, i.e. when the side length of the housing 2, as seen in cross section, is less than 1.6 or 1.5 times the average diameter of the trailing edges of the blades 22 of the impeller 19 with respect to the fan axis.

In Fig. 17 the housing 2, the guide device 1 and the impeller 19 according to the embodiment according to Fig. 16 shown in a side view and in section on a plane through the axis. The flat areas of the outer ring 5 of the guide device 1 are clearly visible in the section. The downstream, axis-parallel area 5a, the flat transition area 5b and the upstream area 5c, bordered on the inside by the upstream edge 23 of the outer ring 5.

In the embodiment, the inflow-side edge 23 of the outer ring 5 of the guide device 1 is located closer to the base plate 21 than to the cover plate 20, viewed in the span direction of the impeller 19, approximately at 75% (preferably 60%-80%) of the span, viewed from the cover plate. This is also advantageous for a tight installation situation of the impeller 19 with respect to the housing 2, i.e. when the side length of the housing 2, viewed in cross section, is less than 1.6 or 1.5 times the average diameter of the trailing edges of the blades 22 of the impeller 19 with respect to the fan axis. For the rest, reference is made to the description of other embodiments, for example according to the Fig. 12 referred to.

The control device 1 of the Fig. 17 The embodiment shown can be easily manufactured from sheet metal, as it is made up of flat areas. To do this, one or more sheet metal parts are trimmed or punched out, folded over if necessary and joined where necessary, for example by welding, tacking, toxing, riveting or screwing.

The guide device 1 can be designed to be load-bearing or non-load-bearing. Necessary suspension elements which attach the impeller 19 and the guide device 1 to the housing 2 are not shown.

Fig. 18 shows, in axial plan view, seen from the downstream side, a housing 2, a guide device 1 and an impeller 19 of another embodiment of a fan. The fan is constructed very similarly to the embodiment according to Fig. 16 and 17 , however, the guide elements 3 also have inclined areas 16 which are connected to the axially aligned parts 15 on the inflow side. This allows the inflow losses of the guide device 1 to be reduced by a more suitable inflow angle of the swirling flow emerging from the impeller 19. The inclined parts 16 are also designed as flat areas. For the rest, please refer to the explanations on Fig. 16 and 17 referred to.

With regard to further advantageous embodiments of the fan according to the invention, reference is made to the general part of the description and to the claims in order to avoid repetition. Finally, it should be expressly pointed out that the exemplary embodiments of the fan according to the invention described above only serve to explain the claimed teaching, but do not restrict it to the exemplary embodiments.

List of reference symbols

1

Guiding device, follow-up device

2

Housing

3

Guide element, guide vane, trailing vane

4

Hub ring, inner ring of the guide device

5

outer ring of the guide device, annular flow element

5a,b,c

flat areas of the outer ring of the guide device

6

outer flow area

7

inner flow area

8

Mounting area within the hub ring

9

Inlet nozzle

10

outer diffuser

11

inner end of a guide element

12

outer end of a guide element

13

Inflow edge of a guide element

14

Trailing edge of a guide element

15

axially aligned part of a guide element

16

employed part of a guide element

17

Transition area of a guide element

18

Fixing provision in the receiving area

19

Wheel

20

Cover plate of the impeller

21

Bottom disc of the impeller

22

Blade of the impeller

23

inflow edge of the outer ring of the guide device

24

outer edge of the bottom plate of the Wheel

25

Suspension strut

26

axially aligned area of the outer ring, demoulding area

27

conical area of the outer ring

28

downstream edge of the outer ring of the guide device

29

Area for a wheel

30

Mounting provision for motor on impeller

31

Flow exit from the impeller

32

suspension

33

Attaching the suspension to the housing

34

Motor

35

Motor rotor

36

Stator of the engine

37

Hubcap

38

Hub ring of the wheel

24

outer edge of the bottom disc of the impeller

25

Suspension strut

26

axially aligned area of the outer ring, demoulding area

27

conical area of the outer ring

28

downstream edge of the outer ring of the guide device

29

Area for a wheel

30

Mounting provision for motor on impeller

31

Flow exit from the impeller

32

suspension

33

Attaching the suspension to the housing

34

Motor

35

Motor rotor

36

Stator of the engine

37

Hubcap

38

Hub ring of the wheel

Claims (14)

1. Fan, in particular an axial, radial or diagonal fan, having a fan impeller (22) and a guide device (1) which is arranged downstream in the housing/flow channel (6), wherein the guide device comprises guide vanes (3) which when viewed in the span width direction or radial direction extend over only a portion of the housing/flow channel,
   wherein the guide device has a structure which acts as a diffusor and which has a flow cross-section which gradually expands when viewed in the throughflow direction and wherein downstream of the impeller two throughflow regions are formed, of which the inner throughflow region which is closer to the axis when viewed in the span width direction is delimited by the hub ring of the guide device and by an outer ring (5) of the guide device, and wherein the outer throughflow region which is remote from the axis when viewed in the span width direction is delimited by the outer ring of the guide device and by the wall of the housing (2).
2. Fan according to claim 1, characterised in that the guide vanes extend approximately over half of the entire radial span width housing/flow channel.
3. Fan according to claim 1 or 2, characterised in that the guide device has a smaller diameter than the fan impeller.
4. Fan according to any one of claims 1 to 3, characterised in that the outer ring is constructed and arranged substantially as a rotation member or rotationally symmetrically with respect to the fan axis.
5. Fan according to claim 4, characterised in that the outer ring is in the form of an element which tapers conically from the inflow side to the outflow side in such a manner that the region close to the guide vanes is suitable for undercut-free demoulding from a casting tool when viewed in an axial direction.
6. Fan according to claim 4 or 5, characterised in that the contour of the outer ring is increasingly powerfully curved from the outflow side thereof to the inflow side thereof so that it has with respect to a preferably radial flow from the impeller no or only a small angle of attack, and redirects this flow preferably in an axial direction or parallel with the fan axis.
7. Fan according to any one of claims 1 to 6, characterised in that the guide vanes have in a radial extent a curved, preferably sickle-like path, in particular with a bend counter to the rotation direction of the associated impeller, wherein the guide vanes have at least in a radially outer region an angle of inclination greater than 30°, preferably greater than 45°, with respect to the radial.
8. Fan according to claim 7, characterised in that the guide vanes have a first inflow-side region and a second outflow-side region, wherein the inflow-side region may have the profiled cross-section of a wing having an inflow angle with respect to the fan axis at the front edge of the median line in the range from 20° to 50°, and/or wherein the outflow-side region may extend parallel with the fan axis and/or wherein the transition between the regions may be in the form of a bend with a constant tangent or with a non-constant tangent.
9. Fan according to any one of claims 1 to 8, characterised in that the guide device comprises or forms at least a portion of a suspension, wherein the guide device may have on the outer contour means for independent suspension.
10. Fan according to claim 9, characterised in that at the inflow side on the inner contour of the guide device a flange for securing the motor is provided, wherein the motor preferably together with the associated fan impeller is suspended above the guide device on a housing/flow channel.
11. Fan according to claim 9 or 10, characterised in that between the outer ring and a wall of the housing/flow channel there extend suspension struts which comprise flat material and which are arranged upright when viewed in an axial direction and/or which in a similar manner to the guide vanes may be curved and/or in a leaning position.
12. Fan according to claim 9 or 10, characterised in that, in order to secure the guide device, one or more guide vanes is/are extended outwards as far as a wall of the air-guiding channel or an outer housing so that integral securing means are thereby formed.
13. Fan according to any one of claims 1 to 12, characterised in that the guide device is produced from sheet metal and is constructed substantially from planar regions.
14. Fan according to any one of claims 1 to 13, characterised in that the inflow-side edge of the outer ring of the guide device is arranged downstream of the impeller vanes in the flow direction, wherein the position thereof when viewed in the span width direction is between the two ends of the impeller vanes, preferably approximately at the centre or in a range from 20-80% of the span width extent of the impeller vanes.

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