Motor for a fan, fan, and impeller

EP4758352A1Pending Publication Date: 2026-06-17ZIEHL ABEGG AG

Patent Information

Authority / Receiving Office
EP · EP
Patent Type
Applications
Current Assignee / Owner
ZIEHL ABEGG AG
Filing Date
2025-08-22
Publication Date
2026-06-17

AI Technical Summary

Technical Problem

Existing fan designs require a shaft extending from the motor rotor to attach the impeller, leading to increased assembly effort, costs, and bearing load due to a longer lever arm.

Method used

The impeller is mechanically coupled directly to the rotor's end face using receiving structures such as holes or threads, eliminating the need for a shaft and allowing direct attachment without additional components.

Benefits of technology

This design reduces manufacturing and assembly costs while minimizing bearing load and imbalances, enabling efficient integration of aerodynamics without a physical shaft.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention relates to a motor (7, 7', 7'', 7'''), in particular an external-rotor motor, for a fan (8), to a fan (8) having a motor (7, 7', 7'', 7''') of this kind, and to an impeller for a fan. The motor (7, 7', 7'', 7''') is characterized in that receiving structures (7''') for fastening means (5) for fastening an impeller (1) of the fan are provided on an end face (7'') of a rotor (7') of the motor. Likewise, the impeller (1) is characterized in that the impeller (1) has receiving structures (4) for being fastened to corresponding receiving structures (7''') on an end face (7'') of a rotor (7') of a motor (7, 7', 7'', 7''').
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Description

[0001] MOTOR FOR A FAN, FAN AND IMMER

[0002] The invention relates to a motor for a fan, a fan with such a motor, and an impeller for a fan.

[0003] Fans and corresponding motors and impellers of the type in question have been known in practice for years. Generally, the impeller is attached to the rotor by means of a shaft extending from the motor rotor and an impeller hub. This is shown, for example, in DE20303443U1. The advantage of this approach is that a wide variety of impellers with the corresponding hub can be mounted on the shaft.

[0004] However, a rotor with an integrated shaft is required, which incurs additional costs. Depending on the size, spacer rings are also needed to prevent collisions between the rotor and impeller, as well as a hub with a keyway to connect the impeller to the shaft. The additional components (adapter, screw, washer, key, and possibly washers) result in increased assembly effort and higher costs. Furthermore, the bearing load on the motor increases because the lever arm is longer due to the integrated shaft.

[0005] The present invention is therefore based on the objective of designing and further developing a fan and fan components in such a way that the disadvantages described above are overcome.

[0006] According to the invention, the aforementioned problem is solved by the features of claim 1. Accordingly, the motor in question, which can in particular be an external rotor motor, has a rotor for a fan. On one end face of the rotor, receiving structures for fastening means for attaching an impeller of the fan are provided.

[0007] In accordance with the invention, it has first been recognized that a shaft and corresponding components for receiving the shaft on the hub can be dispensed with if the impeller is mechanically coupled directly to the rotor at its end face without the use of a shaft. For this purpose, receiving structures, such as holes or threads, for fastening elements, such as screws, are provided on the end faces of both the rotor and the impeller. In particular, the receiving structures can be designed to attach the impeller to the rotor without the use of a rotor shaft extending from the rotor. By utilizing the receiving structures and the fastening elements, the impeller can be mechanically coupled to the motor rotor without the need for a shaft, thereby overcoming the aforementioned disadvantages.This also solves the problem of enabling an integration of aerodynamics that is no longer achieved via a physical shaft.

[0008] In the present invention, the motor and impeller are coupled by the receiving structures on the end face of the rotor. The end face of the rotor corresponds to a circular or annular surface of the motor, perpendicular to the direction of rotation. _,The end face of the motor is defined as the circular or annular surface perpendicular to the rotor's axis of rotation and facing the fan impeller. Specifically, the end face can be the continuous surface of the rotor that is perpendicular to the rotor's axis of rotation, faces the fan impeller, and is axially furthest from the motor's center of gravity or center point. The end face of the motor does not include, for example, attachments or protruding parts of the rotor that, while also perpendicular to the axis of rotation, are not part of the continuous surface on the rotor's end face. It should be noted that a continuous surface is also considered a continuous surface if it has an annular shape.

[0009] In principle, various fastening means are conceivable for mounting the impeller to the motor. To allow for reversible mounting of the impeller, the mounting structures can be threaded or have holes for receiving screws to secure the impeller. Screws have proven effective for the mechanical coupling of impellers and motors. In the present invention, several mounting structures, such as multiple holes, and corresponding fastening means are used to couple the impeller to the motor rotor. The mounting structures can preferably be arranged in an annular configuration concentric with the rotor at the rotor's end face. In particular, a rotationally symmetrical arrangement can be chosen to avoid imbalances during fan operation.

[0010] Another measure to avoid imbalances is to provide a centering structure on the rotor's end face. For example, the rotor can have at least one structure on its end face, particularly a conical or cylindrical structure, to center the impeller on the rotor. This structure, which can be, for example, a flange or collar, ensures the impeller is centered relative to the rotor. Thus, the impeller can be directly connected to the rotor. The rotor is centered on the impeller by means of the structure on its end face, which engages with a corresponding structure, such as the impeller hub. This eliminates the need for an additional centering adapter. Preferably, the centering structure, i.e., the flange or collar, does not need to accommodate the fastening elements. In particular, the receiving elements can be located outside the structure.This avoids the need for the structure to have a minimum size in order to possess the recording structures.

[0011] The end-face connection of the impeller to the rotor can be facilitated by various design features. Preferably, a flat surface is provided on the rotor's end face to serve as a bearing for the impeller. Furthermore, to prevent collisions between the impeller and the rotor, the rotor head can be semi-circular (dome-shaped) to ensure sufficient clearance between the parts to be joined. In summary, the rotor head, encompassing the end face, can be semi-circular with a flat surface on its end face. The mounting structures are arranged on this flat surface. _,This design simplifies the end-face connection of the impeller to the rotor. Furthermore, as previously described, the rotor can incorporate structures or geometries for centering the impeller. These can be conical or cylindrical to ensure the impeller is mounted centrally and to prevent imbalance.

[0012] The present invention has the advantage that a shaft extending from the rotor towards the impeller can be dispensed with. Thus, the rotor is preferably a rotor without an extended shaft. This avoids the aforementioned increased load on the motor and reduces manufacturing and assembly costs.

[0013] The invention also relates to a corresponding fan comprising the previously described motor and an impeller. The impeller is attached to the mounting structures on the end face of the motor rotor by means of fastening devices. Using the mounting structures and the fastening devices, the impeller can be mechanically coupled to the motor rotor without the need for a separate shaft, thereby overcoming the disadvantages of known fans with a separate shaft.

[0014] The invention can be applied to various types of fans, such as axial, diagonal, or radial fans. Preferably, the fan is an axial fan with an axial impeller.

[0015] In principle, various fastening methods are conceivable for mounting the impeller to the motor. To allow for reversible attachment, the impeller can, for example, be fastened to the mounting structures on the front of the rotor using screws.

[0016] The fastening via the fasteners and the respective mounting structures on the impeller and on the end face of the rotor is generally sufficient for the mechanical coupling of the impeller and rotor – an additional mechanical coupling via a shaft is not necessary. Thus, the rotor can be attached to the impeller without a shaft.

[0017] Another aspect of the present invention relates to a corresponding impeller for the aforementioned fan. Such an impeller has mounting structures for attachment to corresponding mounting structures on an end face of a motor rotor. The mounting structures allow the impeller to be mechanically coupled directly to the end face of the rotor without the need for a shaft. This overcomes the disadvantages of known fans with a visible shaft.

[0018] Advantageously, such an impeller can be designed to be used with both motors with mounting structures on the end face and motors with extended shafts. In particular, the impeller can have mounting structures for attaching it to the rotor end face of a motor of the first type. These same mounting structures can also be provided to attach an adapter to the impeller for mounting it on the extended shaft of a second type of motor. The adapter can be attached to a hub of the impeller using appropriate fasteners, such as screws, and the adapter can be attached to the shaft. This allows the impeller to be used for different motor types, thereby reducing manufacturing and storage costs. This also solves the problem of modifying an existing impeller without tooling changes. ,It is to be attached to the front of an engine.

[0019] There are now various ways to advantageously elaborate and further develop the teaching of the present invention. For this purpose, reference should be made, on the one hand, to the claims subordinate to claims 1 and 9, and on the other hand, to the following explanation of preferred embodiments of the invention with reference to the drawing. In conjunction with the explanation of the preferred embodiments of the invention with reference to the drawing, generally preferred embodiments and further developments of the teaching are also explained. The drawing shows

[0020] Fig. 1 shows an isometric view of an impeller of an axial fan;

[0021] Fig. 2 shows a cross-section of the impeller with an adapter for mounting on a motor shaft;

[0022] Fig. 3 shows an isometric view of the impeller, in which a

[0023] The cover cap of one of the wheel hubs has been removed;

[0024] Fig. 4 shows a cross-section of a fan with a rotor, on whose

[0025] The end face of an impeller is mechanically coupled without the use of a shaft;

[0026] Fig. 5 shows an isometric view of the fan, with part of the impeller hidden to illustrate the mounting;

[0027] Fig. 6 shows a side view of the fan;

[0028] Fig. 7 shows a sectional view of the fan, with a focus on the attachment of the impeller to the rotor;

[0029] Fig. 8 shows another isometric view of the fan;

[0030] Fig. 9 shows another isometric view of the fan, with the fan rotor including a centering structure;

[0031] Fig. 10 shows a side view of the fan with a rotor with a centering structure.

[0032] Impellers or other types of rotors are often mechanically coupled to the motor via a shaft extending from the motor's rotor. Such an impeller is shown, for example, in Figures 1 to 3. Figure 1 shows an isometric view of an impeller 1' of an axial fan. The impeller T is shown with a hub 2' (with cover) and blades 3. Figure 2 shows a cross-section of the impeller. Inside the hub 2', an adapter 6 can be seen attached to holes 4' in the hub by means of screws 5'. This adapter 6 is used to mechanically couple the impeller 1' to the motor (not shown) via a motor shaft. Fig. 3 shows an isometric view of the wheel T. In the view of Fig. 3, the cover cap of the hub 2' has now been removed, so that it is visible how the adapter 6 is coupled to the hub 2' of the wheel T by means of the screws 5' and corresponding nuts.

[0033] Figures 4 to 8 show a fan 8 according to the invention, comprising a motor 7 and an impeller 1, which are mechanically coupled to each other without a shaft. Figure 4 shows a cross-section of the fan 8 with a motor 7 and a rotor 7', to whose end face 7" the impeller 1 is mechanically coupled without the use of a shaft. The axial impeller 1 is connected at its end face 7" to the rotor head 7"" of a rotor 7' of the motor 7. The rotor head 7"" has a semicircular or dome-shaped form with a flat surface 7" on its end face. _, The gate head is designed so that the impeller 1 can be screwed directly onto it, eliminating the need for a separate shaft. Furthermore, the adapter for connecting the impeller to the rotor is no longer required. Assembly is also simplified, as the impeller is mounted directly to the rotor.

[0034] The assembly is carried out via mounting structures 7'" on the end face 7" of the rotor 7' and corresponding mounting structures 4 on the hub 2 of the impeller 1, as shown in Fig. 5. Fig. 5 shows an isometric view of the fan 8, with part of the impeller 1 hidden to illustrate the mounting. This reveals the mounting structures 7'" on the end face of the rotor 7'. Depending on the design, these mounting structures 7'" can, for example, be threaded. _,The receiving structures 7'" can be loose holes (bores), or they can be threaded. The receiving structures 7'" are arranged in an annular configuration concentric with the rotor 7' (i.e., with the rotor's axis of rotation) on the end face 7" of the rotor. Corresponding receiving structures 4, such as holes or bores, are provided in the hub 2 of the impeller 1. The impeller 1 is connected to the rotor head of the rotor 7' by means of screws 5 (and optionally nuts).

[0035] Fig. 6 shows a side view of the fan 8. Here, the impeller 1 is mounted on the end face 7" of the rotor. Fig. 7 shows another sectional view of the fan 8, focusing on the attachment of the impeller 1 to the rotor 7'. The mounting structures 4 on the impeller are shown in detail, as are the screws 5 for connecting the impeller 1 to the rotor 7'. Fig. 8 shows another isometric view of the fan 8, showing the impeller 1 and the motor 7 with the rotor 7'. The impeller 1 is connected to the rotor 7' without the use of a shaft.

[0036] The end-face connection of an impeller, such as an axial fan, to a rotor, as shown in Figures 4 to 8, enables direct end-face attachment of the aerodynamic element without an additional component (such as a hub or adapter) or a shaft on the rotor. The rotor and aerodynamic element (impeller) are designed so that the impeller can be screwed onto the rotor's end face. In Figures 4 to 8, the rotor is designed to allow the use of a hub that can also be coupled to a shaft via an adapter, and the impeller can be screwed onto the rotor's end face. In other words, the mounting structures 4 on the impeller are provided for attaching the impeller 1 to a rotor end face 7' of motors of a first motor type. _,The same mounting structures 4 can also be provided with an adapter (e.g., adapter 6 from Fig. 2) for mounting a second motor type on the impeller's shaft. Thus, in some embodiments, the impeller can also be coupled to a second motor type, as shown in Figs. 1 to 3. This makes it particularly possible to attach existing impellers / aerodynamics to the front face without modification. Likewise, the existing aerodynamics can be attached to the front face of the motor without tooling changes. Furthermore, no additional components or shaft are required to attach the impeller to the rotor. This reduces assembly costs and handling. Bearing loads are also reduced due to weight savings and a shorter lever arm.

[0037] To ensure centering of the impeller on the rotor, geometries for centering the impeller can be provided on the rotor. Fig. 9 shows a more detailed isometric view of the fan, with the rotor 7' of the fan

[0038] Figure 8 includes a centering structure 9. Figure 10 shows a side view of such a fan 8. In Figures 9 and 10, a centering structure is shown in particular.

[0039] 9, with a cylindrical shape, i.e., a centering structure 9, designed as a flange or collar, is shown, projecting from the flat surface 7" of the end face towards the impeller 1. The centering structure 9, together with an opening in the hub 2 of the impeller, ensures centering. The centering structure 9 engages in the opening in the hub.

[0040] Regarding further advantageous embodiments of the device according to the invention, reference is made to the general part of the description and to the attached claims in order to avoid repetition.

[0041] Finally, it should be expressly pointed out that the above-described embodiments of the device according to the invention serve only to discuss the claimed teaching, but do not limit it to the embodiments described above.

[0042] Reference symbol list

[0043] 1, 1' impeller, impeller

[0044] 2, 2' hub

[0045] 3 wings

[0046] 4, 4' mounting structures, holes on hub

[0047] 5.5 screws

[0048] 6 adapters

[0049] 7 engine

[0050] 7' Rotor

[0051] 7" end face, flat surface

[0052] 7'" recording structures, holes on the front of the rotor

[0053] 7" rotor head

[0054] 8 fans

[0055] 9 Centering structure, collar, flange

Claims

Claims 1. Motor, in particular external rotor motor, for a fan, characterized in that receiving structures for fastening means for fastening an impeller of the fan are provided on an end face of a rotor of the motor.

2. Motor according to claim 1, characterized in that the receiving structures are threads or holes for receiving screws for fastening the impeller.

3. Motor according to claim 1 or 2, characterized in that the receiving structures are designed to attach the impeller to the rotor without using a rotor shaft extending from the rotor.

4. Motor according to one of claims 1 to 3, characterized in that the receiving structures are arranged in an annular arrangement concentric with the rotor on the front face of the rotor.

5. Motor according to one of claims 1 to 4, characterized in that the rotor is a rotor without an extended shaft.

6. Motor according to one of claims 1 to 5, characterized in that the rotor has at least one structure, in particular a conical or cylindrical structure, on its end face to center the impeller on the rotor.

7. Motor according to claim 6, characterized in that the structure is a flange or collar, and / or characterized in that the receiving structures are arranged outside the structure.

8. Motor according to one of claims 1 to 7, characterized in that a rotor head of the rotor, which comprises the end face, is semicircular with a The flat surface is located on the front face, with the receiving structures arranged on the flat surface.

9. Fan, in particular axial fan, comprising a motor, in particular an external rotor motor, according to any one of claims 1 to 8 and an impeller, wherein the impeller is attached to the receiving structures on the end face of the rotor of the motor by means of fastening means.

10. Fan according to claim 9, characterized in that the fan is an axial fan.

11. Fan according to claim 9 or 10, characterized in that the impeller is attached to the mounting structures on the front face of the rotor by means of screws.

12. Fan according to one of claims 9 to 11, characterized in that the rotor is centered on the impeller at the end face of the rotor by means of a structure, in particular a conical or cylindrical structure.

13. Impeller, in particular vane wheel, for a fan, characterized in that the impeller has receiving structures for attachment to corresponding receiving structures on an end face of a rotor of a motor.

14. Impeller according to claim 13, characterized in that the impeller has the receiving structures for attaching the impeller to a rotor end face of motors of a first motor type, wherein the receiving structures are additionally provided to attach an adapter for mounting on an executed shaft of a motor of a second motor type to the impeller.