FAN SYSTEM WITH AN ELECTRIC MOTOR

Description

[0001] The invention is based on a fan system with an electric motor.

[0002] It is already known to screw the fan wheel of a fan system directly onto the rotating rotor. However, this method couples forces from the electric motor's magnetic circuit directly into the fan wheel, leading to unwanted vibrations and, consequently, unwanted noise. State-of-the-art fan systems are known, among others, from US Pat. No. 4,203,704 and WO 2013 / 032923 A2.

[0003] The invention is based on a fan system with an electric motor, wherein the electric motor has a rotor and the rotor is rotatably mounted relative to a stator, wherein a fan wheel is arranged on an end face of the rotor in a rotationally fixed manner via at least one connection element in a connection section of the rotor. It is proposed that at least one decoupling element be provided, which encompasses the at least one connection section in its respective radially outer region, wherein the decoupling element is provided to mechanically decouple the connection section of the rotor from a rotor section surrounding the connection section.

[0004] The fan system according to the invention and the rotor according to the invention with the features of the independent claims have the advantage that, by means of the decoupling element, the forces of the magnetic circuit of the electric motor are not transmitted directly to the fan wheel, but rather, by extending the guide support structure of the force flow, a corresponding mechanical decoupling between the magnets of the rotor and the connected fan wheel can be provided. In this way, the noise generation of the fan system can be advantageously reduced. At the same time, the rotor according to the invention can advantageously be manufactured particularly simply and cost-effectively. For example, it is possible to integrate such a decoupling into existing fan systems without having to take further design measures.Furthermore, by integrating the decoupling into the electric motor itself, the variety of variants of the connection of the fan wheel to the rotor can be advantageously reduced, thereby reducing additional tool or parts costs.

[0005] In the context of the present invention, the term "motor shaft" refers to a physical machine element that supports the rotor bearings. Furthermore, the term "rotational axis" refers to an imaginary axis around which the rotor rotates, in the sense of a rotational axis. Unlike the motor shaft, which represents a physical machine element, the rotational axis is a purely imaginary axis.

[0006] Furthermore, within the scope of the present invention, a decoupling element can be understood as an element which allows a relative movement of the components adjacent to the decoupling element and thus at least reduces, in particular prevents, a direct transmission of force.

[0007] In the context of the present invention, a connecting element can be understood as a means which enables the torque of the rotor to be transmitted to the fan wheel. In particular, such a connecting element can be understood as an element which provides a rotationally fixed connection. Such a connecting element can be a screw connection, for example. However, it is also conceivable for the connecting element to be designed as part of a rivet, pin or bolt connection. Other connection techniques are also conceivable here, provided they are suitable for transmitting the forces of the rotor to the fan wheel. Furthermore, in the context of the present invention, a connecting section of the rotor can be understood as an area which interacts with the corresponding connecting element.If the connecting element is designed as a screw connection, this can, for example, be a hole to accommodate the corresponding screw.

[0008] According to the invention, the decoupling element essentially continuously encompasses the at least one connection section in its respective radially outer region. In this context, the radially outer region can be understood to mean the rotor region which is arranged radially outside the connection section. In other words, the radially outer region in this context represents the region which is arranged radially outside the pitch circle radius, wherein the circle center lies on the axis of rotation of the motor and the circular line passes centrally through the connection section. Thus, the decoupling element essentially completely encloses the connection section in this region and mechanically decouples the connection section of the rotor from the rotor section surrounding the connection section in this region.

[0009] According to an advantageous embodiment of the electric motor, it is designed as an external rotor.

[0010] According to the invention, the decoupling element is designed as an axially continuous decoupling gap. Within the scope of the present invention, a decoupling gap can be understood in particular as a narrow, elongated opening designed as a through-hole. Such a decoupling gap can be manufactured cost-effectively using particularly simple means.

[0011] The features listed in the subclaims enable advantageous further developments of the fan system or the rotor.

[0012] To optimally utilize the available space and maximize the length of the guide support structure and thus the force flow path, a further development of the invention provides that the decoupling element, which encompasses the radially outer region of the connecting section, extends radially to an inner region of the rotor. In the context of the present invention, the inner region can be understood as the rotor surface that is arranged near the motor shaft. In particular, this can be understood as a substantially circular region arranged concentrically to the axis of rotation, the radius of which is smaller than half the radius of the end face of the rotor, preferably smaller than a quarter of the radius of the end face of the rotor, in particular smaller than an eighth of the radius of the end face of the rotor.

[0013] An advantageous development of the invention further provides that the decoupling element is substantially U- or V-shaped. Preferably, the opening of the substantially U- or V-shaped decoupling element is arranged facing the motor shaft, and the circular segment or the tapered end of the substantially U- or V-shaped decoupling element is arranged radially outwardly and encompasses the corresponding connection section.

[0014] According to an advantageous development of the invention, a force flow-optimized connection can be provided in that the gap width of the decoupling element increases with increasing distance from the connection section.

[0015] According to an advantageous development of the invention, it is provided that at least one elastic element extending in the radial direction is arranged on the end face of the rotor, which is designed as a rotor disk, on the radially outer region of which at least one connection section is arranged, wherein the elastic element is encompassed by the decoupling element and wherein the elastic element is connected, in particular integrally connected, to the inner region of the rotor in a coupling section.

[0016] In the context of the present invention, the end face of the rotor can be understood as the surface of the rotor that laterally delimits the rotor in the direction of the axis of rotation. The term "end face" is not limited to a flat surface; rather, the end face can have any surface contour. Preferably, however, the end face extends substantially in the radial direction and is substantially at least partially flat or planar.

[0017] According to a further advantageous development of the invention, it can moreover be provided that the rotor is made entirely or at least partially from plastic. For example, it is conceivable that the rotor comprises a metallic material in sections and is made partially from a plastic. Furthermore, it is also conceivable that the rotor has a base material into which fibers or particles are introduced at least in sections to optimize the material properties. A particularly preferred embodiment of the invention provides that in particular the elastic element is made of a different material than a predominant part of the rotor. Furthermore, other material combinations are also conceivable. For example, it is also conceivable that the rotor is made at least in sections from vulcanized natural rubber and, alternatively or additionally, from vulcanized synthetic rubber.What is essential to the invention is only that the rotor has at least one magnetic return ring.

[0018] Preferably, the elastic element is designed as a flexible tab, in particular as a spring tongue. This provides appropriate decoupling of the magnetic circuit forces from the fan impeller.

[0019] Particularly uniform force transmission and optimal dimensioning can be achieved by distributing several, preferably three, elastic elements around the circumference, particularly at equal distances from one another. Of course, other embodiments are also conceivable.

[0020] According to an advantageous development of the invention, it is further provided that a connecting web is arranged in the circumferential direction between two decoupling elements of adjacent elastic elements, which connecting web extends in the radial direction and connects the inner region of the rotor assigned to the motor shaft and the outer region of the rotor assigned to the magnets.

[0021] To minimize the amplitude of movement and ensure optimal power transmission to the fan impeller, a further advantageous development of the invention provides for stiffening elements to be arranged in the area of ​​the coupling section and, alternatively or additionally, also in the area of ​​the connecting web. A particularly simple and cost-effective stiffening can be achieved in particular by forming the stiffening element in one piece on the rotor and, for example, as a material curvature, bead, or rib.

[0022] An advantageous development of the invention further provides that the rotor is manufactured at least in sections as a stamped and bent part from sheet metal. According to a particularly preferred development of the invention, the rotor is formed at least in sections from at least two sheet metal layers arranged one above the other in the axial direction. The layers can preferably be manufactured in one machining process using the same stamping and bending tool. Of course, it is also conceivable to produce the layers separately from one another, depending on the selected material composition, using a corresponding manufacturing process tailored to the material combination. It is also conceivable for the layers of the rotor to be formed at least partially from different materials. An advantageous development of the invention provides that the layers are each formed as a one-piece component.However, it is also conceivable that the layers are each designed as multi-part components.

[0023] The drawings show exemplary embodiments of the fan system and the rotor, respectively, and are explained in more detail in the following description. They show: Figure 1 shows a sectional view of a fan system according to the invention, Figure 2 shows a first embodiment of a rotor in a plan view, Figure 3 shows a second embodiment of a rotor in a perspective view, Figure 4 shows a third embodiment of a rotor in a perspective view and Figure 5 shows a fourth embodiment of a rotor in a perspective view.

[0024] In the different versions, identical parts have the same reference numbers.

[0025] Figure 1shows a fan system 10 with an electric motor 12 and a fan wheel 14. The fan wheel 14 has a plurality of fan blades which are designed to convey cooling air when the fan wheel 14 rotates. Figure 1 The electric motor 12 of the fan system 10 shown, for example designed as an external rotor, has a fixed part, the stator 16, and a rotating part, the rotor 18.

[0026] An electric motor of the external rotor type, as used in Figure 1 The rotor 18, as shown, is characterized in that the radially inner part is stationary during operation, while the radially outer part rotates. A plurality of windings 20 are arranged on the stator 16. The rotor 18, in turn, has magnets 22. When current flows through the windings 20, the magnetic field of the stator 16 drives the rotor 18.

[0027] It is pointed out that the fan system 10, in particular the electric motor 12 in Figure 1 is only shown schematically, since the structure and functionality of a suitable electric motor 12 are sufficiently known from the prior art, so that a detailed description of the fan system 10 is omitted here for the sake of brevity and simplicity of the description.

[0028] As in Figure 1As can be clearly seen, the rotor 18 is essentially pot-shaped. The windings 20 and magnets 22 are arranged within the pot-shaped design of the rotor 18. The pot-shaped rotor 18 has an end face 24 extending essentially in the radial direction. The end face 24 is essentially at least partially flat and forms the base of the pot-shaped rotor 18. In addition to the end face 24 extending in the radial direction, the rotor 18 has a circumferential collar 26 which is arranged on the radially outer edge of the radially outer region 25 of the rotor 18 and forms a circumferential cylindrical side wall of the rotor 18. The circumferential collar 26 extends essentially at least partially in the axial direction.

[0029] The open area of ​​the rotor 18 opposite the end face 24 of the pot-shaped rotor 18 is, as shown in Figure 1As can be clearly seen, it is shielded by a motor mount 28. The arrangement of the pot-shaped rotor 18 and the motor mount 28 acting as a cover results in an essentially enclosed space for the magnets 20 and windings 20.

[0030] At the Figure 1 In the embodiment shown, the motor shaft 30 is connected in a rotationally fixed manner to the motor support 28 or to the stator 16. Such a rotationally fixed connection can be provided in particular by injecting the motor shaft 30 into the motor support 28. The magnets 22 are arranged on the inner side of the axially extending circumferential collar 26 facing the motor shaft 30. As shown in Figure 1 As shown, the motor shaft 30 has a fixed end 32, a free end 34 and an axis of rotation 36 about which the rotor 18 with the fan wheel 14 and the stator 16 are rotatably mounted relative to one another.

[0031] As in Figure 1As shown, the axis of rotation 36 runs in the sense of an imaginary straight line extending to infinity, in particular centrally through the motor shaft 30 and corresponds to the center axis of the motor shaft 30. For the rotatable mounting of the rotor 18 relative to the stator 16 about the axis of rotation 36, a cylindrical bearing seat 40 extending essentially in the axial direction is arranged on the rotor 18 on its side facing the motor shaft 30. A bearing 42 is arranged inside the bearing seat 40 of the rotor 18. According to the Figure 1 In the illustrated embodiment of the invention, the bearing arrangement comprises two bearings, each of which is seated with its outer ring in the bearing seat 40 of the rotor and with its corresponding inner ring in a rotationally fixed manner on the motor shaft 30. Of course, other bearing arrangements and bearing designs are also conceivable.

[0032] When the electric motor 12 starts, the rotor 18 is set in rotation. To drive the fan wheel 14, it is non-rotatably mounted on the front side 24 of the rotor 18. As shown in Figure 1 As is indicated schematically, for this purpose the fan wheel 14 is arranged in a rotationally fixed manner via at least one connecting element 50 in a connecting section 52 of the rotor 18. According to the Figure 1 In the illustrated embodiment of the invention, the connecting element 50 is designed as a screw connection. However, other connection forms are also conceivable. The connecting section 52 of the rotor 18, on which the corresponding connecting element 50 is arranged, is located on the end face 24 of the rotor 18, with the connecting section 52 preferably being arranged in a radially outer region 25 of the end face 24 and thus preferably in the region of the magnets 22.

[0033] Alternating forces from the magnetic circuit of the electric motor 12 of the fan system 10 can lead to corresponding undesired structural deformations in the rotor 18, which can occur particularly in conjunction with structural resonances. In known systems, these undesired movement amplitudes are transmitted to the fan wheel 14, which is non-rotatably mounted via the connecting element 50. These movement amplitudes of the fan wheel 14, which has a correspondingly larger surface area than the rotor 18 itself, then lead to the transmission of vibrations to the air and thus to undesired noise generation. The largest movement amplitudes of the rotor 18 occur particularly in the radially outer region 25, i.e., in the area of ​​the magnets.However, since it is desirable for design reasons that the connection of the fan wheel 18 be arranged precisely in this radially outer region 25, which is maximally excited, a corresponding decoupling element 60 is provided. Based on the view in . Figure 1 The corresponding decoupling element 60 is not shown here. Corresponding embodiments of the invention are therefore explained and illustrated in more detail in the following figures.

[0034] Figure 2 shows a first embodiment of the invention. In Figure 2 A top view of the front side 24 of the rotor 18 is shown. As in Figure 2As can be clearly seen, the rotor is essentially circular and has an end face 24 extending essentially in the radial direction. The end face 24 is essentially at least partially flat. On the radially outer edge of the end face 24 there is arranged the circumferential collar 26 extending essentially in the axial direction, on the inner wall of which the magnets 22 (not visible here) are arranged. In its central region the rotor 18 has a bearing seat 40. In the assembled state the bearing 42 for rotatably supporting the rotor 18 around the stator 16 or the motor shaft 30 is arranged inside the bearing seat 40 of the rotor 18.

[0035] According to the In Figure 2In the illustrated embodiment of the invention, three connection sections 52 are arranged on the end face 24 of the rotor 18. According to the embodiment of the invention illustrated here, these connection sections are designed as bores for receiving the connection elements 50 designed as screws. As already mentioned, other connection forms or fastening means are also conceivable. The fan wheel 14 is rotationally fixedly attached to the end face 24 of the rotor 18 via the connection elements 50, and the torque of the rotor is transmitted to the fan wheel 14.

[0036] According to the Figure 2 In the embodiment of the invention shown, the three connecting sections 52 are arranged substantially equidistant from one another and are located substantially on the same pitch circle radius 56 around the imaginary axis of rotation 36. Of course, the number of connecting sections 52 and their arrangement both relative to one another and on the rotor 18 can vary.

[0037] As already mentioned, the greatest movement amplitudes of the rotor 18 occur particularly in the radially outer region 25, i.e., in the region of the connecting sections 52. To prevent these movements of the rotor from being transmitted unhindered to the fan wheel 14, the rotor has at least one corresponding decoupling element 60.

[0038] According to the Figure 2In the illustrated embodiment of the invention, three decoupling elements 60 are provided, corresponding to the number of connecting sections, wherein each decoupling element 60 essentially continuously encompasses the corresponding connecting section 52 in its respective radially outer region. According to the invention, the decoupling elements 60 are provided to mechanically decouple the respective connecting sections 52 from the rotor section 62 surrounding the corresponding connecting section 52. This mechanical decoupling lengthens the path of the force flow from the magnets 22 via the rotor 18 to the fan wheel 14, which advantageously reduces the movement amplitude of the connecting sections 52 and consequently leads to reduced noise generation.

[0039] According to the Figure 2In the embodiment of the invention shown, the decoupling elements 60 are designed as through-openings or as decoupling gaps. According to the embodiment of the invention shown here, the gap width 64 of the decoupling element 60 is essentially constant over the entire longitudinal extent of the decoupling element 60. However, other gap width profiles are also conceivable, as is particularly the case in the Figures 3 and 4 is shown in more detail.

[0040] In order to optimize the path of the force flow or the guide support structure, the decoupling element extends from the radially outer region 25 to an inner region 66, that is to say to a region in which the bearing seat 40 for the motor shaft 30 is arranged.

[0041] According to the Figure 2In the embodiment of the invention shown, the decoupling gap is substantially U-shaped, wherein the arc segment of the substantially U-shaped decoupling gap 60 encompasses or encloses the respective connection section and wherein the opening of the decoupling gap faces the interior region.

[0042] According to the Figure 2 In the illustrated embodiment of the invention, the respective free ends 70 of the substantially U-shaped decoupling element 60 extend substantially in the radial direction. The decoupling element 60, or rather the decoupling gap, thus encloses an elastic element 74 extending substantially in the radial direction, which is connected to the inner region 66 of the rotor.

[0043] According to the Figure 2In the illustrated embodiment of the invention, the elastic element 74 is designed as a bending tab or bending tongue and has the respective connection section 52 for the fan wheel 14 on its radially outer section. Corresponding to the U-shaped design of the decoupling element 60, the bending tab has a rounded radially outer region. According to the invention, the respective free ends of the decoupling element 60 terminate at a pitch circle radius 76, which is smaller than the pitch circle radius 56 of the associated connection section 52.

[0044] According to the number of connection sections 52, Figure 2In the embodiment of the invention shown, three elastic elements 74 are provided, wherein the respective connecting section 52 is arranged on the corresponding radially outer regions of the elastic elements 74. By means of these elastic elements 74 with the corresponding decoupling elements 60 surrounding the elastic elements 74, the direct guide support structure between the connecting section 52 and the rotor section 62 surrounding the connecting section is interrupted, so that the path of the force flow is correspondingly extended by the radial length of the elastic element 74 and thus noise can be reduced accordingly, as described above. For symmetrical force introduction, it can be advantageous if the connecting sections 52 and thus also the elastic elements 74 are arranged equidistantly distributed around the circumference. Figure 2The rotor shown can, according to an advantageous development of the invention, be designed as a stamped and bent part.

[0045] In addition to the decoupling elements 60 designed as a through-opening, the rotor 18 has, according to the Figure 2 illustrated embodiment of the invention has further through openings 80, which can be designed, for example, as ventilation openings for the electric motor 12.

[0046] Between the elastic elements 74 distributed around the circumference, the rotor 18 has connecting webs 82, which extend essentially in the radial direction and connect the inner region 66 of the rotor 18, which is associated with the motor shaft 30, and the outer region 25 of the rotor, which is associated with the magnets 22. These connecting webs 82 thus form a corresponding part of the guide support structure for transmitting force between the magnets 22 and the fan wheel 14.

[0047] Figure 3shows a further embodiment of the rotor 18 in a perspective view. The rotor 18 essentially corresponds to the rotor according to the Figure 2 illustrated embodiment with the difference that the decoupling elements 60 are essentially V-shaped. The opening of the V-shaped decoupling elements 60 are designed to face the inner region 66. As in Figure 3 As can be clearly seen, the gap width 64 also increases with increasing distance from the corresponding connection section 52, so that the respective free ends 70 have a widened gap.

[0048] Corresponding to the shape of the decoupling elements 60, the elastic elements 74 have a contour that tapers to a point essentially in the direction of the radially outer region 25, so that the coupling region 90 between the elastic element 74 and the inner region 66 is advantageously widened. In contrast to the Figure 2 The embodiment of the rotor 18 shown in Figure 3 The rotor 18 shown further comprises stiffening elements 92 both in the area of ​​the coupling area 90 and in the area of ​​the connecting webs 82, which, in an advantageous further development, support the guide support structure for force transmission.

[0049] According to the Figure 3 In the illustrated embodiment of the invention, the stiffening elements 92 are formed as stiffening ribs integrally with the rotor 18. The stiffening elements 92 are advantageously contoured to optimize loads. There are stiffening elements 92 that have a substantially triangular shape. They are arranged on at least one elastic element 74. Further stiffening elements 92 have the shape of a cut bone and are arranged in the region of the connecting webs.

[0050] Figure 4shows a further embodiment of the invention according to which the ventilation openings 80 of the electric motor 12 are formed as part of the decoupling element 60. According to the Figure 4 In the embodiment shown, the ventilation openings 80 form the respective free ends 70 of the decoupling element 60. The free ends are arranged in the circumferential direction between the elastic elements 74 and the connecting webs 82. By integrating the functions, the additional cutting length required for the decoupling element 60 can be advantageously reduced and the component rigidity can be optimized while maintaining the same functionality.

[0051] Even in such an embodiment, the pitch circle radius 76 of the respective free ends 70 of the decoupling element 60 is smaller than the pitch circle radius 56 of the connecting sections 52, so that these are always arranged radially outside the free ends 70.

[0052] The elastic element, in particular the bending tabs 74 or spring tongues, have, according to the Figure 4 illustrated embodiment has an increasing width, in particular a substantially trapezoidal contour, essentially with increasing radius, wherein the connecting sections 52 or bores are each arranged centrally on the outer circumference.

[0053] The region of the elastic element 74 facing the circumferential collar 26 has a contour with a radius reduced by the radial extension of the decoupling region 60. This results in a uniform distance along the radial axis between the bending tab 74 and the circumferential collar 26. A part of the decoupling element 60 is formed in this region.

[0054] According to the Figure 4In the illustrated embodiment of the invention, both the coupling region and the elastic element 74 are stiffened around the connecting section 52 by means of a stiffening element 92. The stiffening element 92 is designed as a substantially Y-shaped bead. The stiffening element 92 has two legs 75 which extend in a V-shape relative to one another. In particular, the connecting section 52 lies substantially in the circumferential direction between the legs 75. In particular, the stiffening element 92 of each elastic element 74 has a rabbit-head shape. The ears are formed by the legs 75. The free ends of the legs 75 point away from the inner region 66. The legs 75 are connected to one another in the circumferential direction via a connecting means 77. The connecting means is formed in the circumferential direction between the legs 75 of an elastic element 74.The connecting means 77 is part of the stiffening means 92. The connecting means 77 forms the head of the rabbit head-like shape.

[0055] The stiffening elements 92 extend into the inner region 66. Preferably, three elastic elements 74 are formed, each with a stiffening element 92.

[0056] The thickness of the stiffening element 92 decreases with increasing distance from the bearing seat 40.

[0057] The inner region 66 also has a stiffening region whose outer radius is smaller than the radius 76. The stiffening element 92 merges into the stiffening region of the inner region 66.

[0058] The connecting webs 82 arranged between the decoupling elements 60 are also optionally stiffened by a corresponding stiffening element 92. The stiffening element 92 is designed in particular as a rib or bead extending in the circumferential direction.

[0059] The decoupling element 60 completely surrounds the elastic element 74 in a radially outer region 25, so that the spring tongue or the elastic element 74 is mechanically decoupled at its radially outer region from the rotor section 26 surrounding the elastic element 74. The spring tongue or flexible tab 74 can move at its free end in the axial direction independently of the end face 24 of the rotor 18.

[0060] Figures 3 and 4 each show embodiments of the invention according to which the decoupling element 60 ends further outwards with respect to the radial direction than the decoupling element 60 according to the Figure 2 The interior region 66 according to the embodiments of the Figures 3 and 4 thus ends in the radial direction significantly further out than the inner area according to Figure 2 The radius of the inner area 66 according to the Figures 3 and 4The embodiment shown is therefore essentially half as large as the radius of the entire end face 24 of the rotor 18.

[0061] Figure 5 shows a further embodiment of the rotor 18 in a perspective view. The rotor 18 essentially corresponds to the rotor according to the Figure 2 illustrated embodiment, with the difference that the decoupling elements 60 are very thin, in particular at their thinnest, in the region 61 of the connecting sections 52, and that the decoupling element 60, starting from the region 61, merges into two widened regions 70. The widened regions 70 form ventilation openings 80. The ventilation openings 80 each form a free end 70 of the decoupling element 60.

[0062] The ventilation elements 80 are essentially trapezoidal in shape. Region 61 of the decoupling element 60 is essentially semicircular in shape. At its open ends, it merges into regions 70, or the ventilation openings.

[0063] Furthermore, the decoupling element 60 has at least one additional gap 63 in the region 70, which extends towards the inner region 66.

[0064] The gap 63 separates the elastic elements 74 from the connecting webs 82 in the circumferential direction.

[0065] Corresponding to the shape of the decoupling elements 60, the elastic elements 74 have a substantially trapezoidal region 73. The elastic elements 74 increase in size toward the outer region. Adjacent to the trapezoidal region 73, the elastic element is semicircular. The elastic element 74 has a semicircular region 79, in particular a semicircular contour, in the direction of the radially encircling collar 26. The semicircular region 79 adjoins, in particular, a smaller, further trapezoid formed between the trapezoidal region 73 and the semicircular region 79.

[0066] In the coupling area 90 between the elastic element 74 and the inner area 66, stiffening elements 92 are formed, which, in an advantageous further development, support the guide support structure for force transmission. These extend radially across the trapezoidal area 73.

[0067] According to a further development of the invention, the stiffening elements 92 extend to the connecting section 52.

[0068] According to the Figure 3 In the illustrated embodiment of the invention, the stiffening elements 92 are formed as stiffening ribs integrally with the rotor 18. The stiffening elements 92 are advantageously contoured to optimize load.

[0069] The connecting webs 82 arranged in the circumferential direction between the decoupling elements 60, in particular the gaps 63, have a trapezoidal region. This region transitions toward the outer region into a narrower region 83, which in turn transitions into the surrounding rotor section 62.

Claims

1. Fan system (10) having an electric motor (12), wherein the electric motor (12) has a rotor (18), and the rotor (18) is mounted so as to be rotatable relative to a stator, wherein a fan impeller (14) is arranged for conjoint rotation on an end surface (24) of the rotor (18) by means of at least one attachment element (50) in an attachment portion (52) of the rotor (18), wherein at least one decoupling element (60) is provided which is in the form of an axially continuous decoupling gap, characterized in that the decoupling element (60) engages around the at least one attachment portion (52) in the respective radially outer region (25) thereof, wherein the decoupling element (60) is provided for mechanically decoupling the attachment portion (52) of the rotor (18) from a rotor portion (62) surrounding the attachment portion (52).

2. Fan system (10) according to any of the preceding claims, characterized in that the decoupling element (60) extends in the radial direction up to an inner region (66), which is arranged in the region of a motor shaft (30).

3. Fan system (10) according to either of the preceding claims, characterized in that the decoupling element (60) is substantially u- or v-shaped.

4. Fan system (10) according to any of the preceding claims, characterized in that a gap width (64) of the decoupling element (60) increases as the distance from the attachment portion (52) increases.

5. Fan system (10) according to any of the preceding claims, characterized in that at least one elastic element (74), which extends in the radial direction and has at least one attachment portion (52) arranged in its radially outer region, is arranged at the end surface (24) of the rotor (18), which end surface is substantially in the form of a rotor disc, wherein the decoupling element (60) engages around the elastic element (74) and wherein the elastic element (74) is connected, in particular is joined in one piece, to the inner region (66) of the rotor (18) in a coupling portion (90).

6. Fan system (10) according to any of the preceding claims, characterized in that the elastic element (74) is in the form of a bending tab on the rotor disc, in particular in the form of a spring tongue.

7. Fan system (10) according to any of the preceding claims, characterized in that several, preferably three, elastic elements (74) are arranged distributed over the circumference, in particular equidistantly in relation to each other.

8. Fan system (10) according to any of the preceding claims, characterized in that a connecting web (82) is arranged between in each case two decoupling elements (60) of adjacent elastic elements (74) in the circumferential direction, which connecting web extends in the radial direction and connects the inner region (66), which is associated with the motor shaft (30), of the rotor (18) and an outer region (25), which is associated with the magnets (22), of the rotor (18).

9. Fan system (10) according to any of the preceding claims, characterized in that reinforcement elements (92), which are preferably formed in one part with the elastic element (74) and / or the connecting web (82) and which are particularly preferably in the form of beads or ribs, are arranged in the region of the coupling portion (90) and / or the connecting web (82).

10. Fan system (10) according to any of the preceding claims, characterized in that the end surface (24) of the rotor (18) is in the form of a stamped and bent part.