Electric motor having a fan

Abstract

An electric motor having a fan, wherein the electric motor has a stator housing to which a bearing flange of the electric motor is connected, wherein a fan is connected to the bearing flange, in which a bearing, in particular an outer ring of a bearing, is received in order to mount the rotor shaft of the electric motor so as to be able to rotate, wherein the bearing flange has a first radially continuous recess with respect to the axis of rotation of the rotor shaft, through which first recess the airflow conveyed by the fan flows into an internal region surrounded radially by the bearing flange, wherein the bearing flange has a second recess that is spaced from the first recess in the circumferential direction, through which second recess the internal region opens into the external environment of the bearing flange and / or through which second recess the airflow exits from the internal region into the external environment of the bearing flange.

Description

[0001] Electric motor with fan

[0002] Description:

[0003] The invention relates to an electric motor with a fan.

[0004] It is known that an electric motor generates waste heat, which is dissipated into the environment.

[0005] The closest prior art known from EP 0 094 680 B1 is an electric motor with a fan.

[0006] An electric motor is known from DE 10 2008 028 607 A1.

[0007] From EP 1 337 029 A1 a protective and connecting cover in a cooling arrangement for an electrical machine is known.

[0008] The invention is therefore based on the object of developing an electric motor that is as compact as possible.

[0009] According to the invention, the object is achieved in the electric motor according to the features specified in claim 1.

[0010] Important features of the invention in the electric motor with fan are that the electric motor has a stator housing to which a bearing flange of the electric motor is connected, wherein a fan is connected to the bearing flange, in which fan a bearing, in particular an outer ring of a bearing, is received for rotatably supporting the rotor shaft of the electric motor, wherein the bearing flange has a first recess which is radially continuous with respect to the axis of rotation of the rotor shaft and through which the air flow conveyed by the fan flows into an interior region radially surrounded by the bearing flange, wherein the bearing flange has a second recess which is spaced apart from the first recess in the circumferential direction, through which the interior region opens into the outer environment of the bearing flange and / or through which the air flow exits from the interior region into the outer environment of the bearing flange.

[0011] The advantage here is that the motor can be designed compactly, i.e., with a small installation space, without reducing power. This is because the additional cooling of the bearing flange provided by the fan dissipates heat loss from the first bearing of the rotor shaft and any additional shaft seal. This allows for a dedicated fan at each bearing location of the motor. It is also important that the airflow from the first fan cools the inner wall of the bearing flange, and the airflow from the second fan cools the outer wall of the bearing flange.

[0012] In an advantageous embodiment, a fan housing of the fan has a collar that protrudes from the fan housing and rests against a flat connecting surface of the bearing flange. This is advantageous because it allows for a stable mounting of the fan.

[0013] In an advantageous embodiment, a bearing shield for receiving a further bearing of the rotor shaft is arranged on the side of the stator housing facing away from the bearing flange, wherein a second fan wheel is connected to the rotor shaft in a rotationally fixed manner on the side of the stator housing facing away from the bearing flange and is radially surrounded by a fan cover detachably connected to the bearing shield, wherein the air flow conveyed by the second fan wheel flows along cooling fins formed on the outside of the stator housing in the axial direction, in particular parallel to the axis of rotation of the rotor shaft, and in particular then flows along the bearing flange, in particular wherein the fan cover has grille openings passing through the fan cover on its axial end face facing away from the bearing flange, in particular for the inflow, in particular wherein the cooling fins are spaced apart from one another in the circumferential direction, in particular wherein the axial,The radial direction and / or the circumferential direction is relative to the rotational axis of the rotor shaft. The advantage here is that the air flow cools the stator housing on the one hand and the bearing flange on the other, which is thus cooled on both sides.

[0014] In an advantageous embodiment, a terminal box is mounted on the stator housing and connected to the stator housing. The advantage here is that the fan requires only slightly more installation space than the terminal box, because it utilizes the radial clearance area covered by the terminal box within the circumferential angle range covered by the terminal box.

[0015] In an advantageous embodiment, the circumferential angular range covered by the terminal box encompasses the circumferential angular range covered by the fan. The advantage here is that only slightly more installation space is required for the fan.

[0016] In an advantageous design, the terminal box is spaced axially from the fan. This allows the bearing flange to be cooled separately.

[0017] In an advantageous embodiment, the radial clearance area covered by the fan, in particular the fan housing, encompasses the radial clearance area covered by the terminal box. The advantage here is that only slightly more radial expansion is required by the fan.

[0018] In an advantageous embodiment, a flange part is detachably connected to the bearing flange in the interior region radially surrounded by the bearing flange, wherein the rotor shaft projects through a recess in the flange part, wherein a shaft sealing ring is received in the flange part, which seals against the rotor shaft, in particular whose sealing lip therefore runs on the rotor shaft, in particular wherein the flange part is arranged on the side of the bearing flange axially facing away from the stator housing and / or the bearing receptacle of the bearing formed in the bearing flange. The advantage here is that the motor has a fan on both sides, thus enabling more efficient cooling. The fans do not interfere with each other. This is because the air flow of the first fan flows essentially transversely to the rotor shaft axis of rotation and the air flow of the second fan flows parallel, i.e. in the axial direction, to the rotor shaft axis of rotation.

[0019] In an advantageous embodiment, the bearing flange is shaped as a square flange on its side facing the stator housing and as a round flange on its side facing away from the stator housing, particularly for connection to a driven device, in particular a gearbox. It is advantageous that the bearing flange is designed as an interface and can thus be positioned between the various flange types.

[0020] In an advantageous embodiment, the bearing flange has a cylindrical outer surface in the area covered by the connecting surface in the axial direction, which is interrupted in the circumferential angular area covered by the connecting surface in the circumferential direction, in particular for shaping the connecting surface. This is advantageous because it enables simple manufacturing.

[0021] In an advantageous embodiment, one or more cooling fins on the bearing flange protrude in the axial direction into the interior area radially surrounded by the bearing flange, in particular, and the flange part connected to the bearing flange and accommodating a shaft seal that seals against the rotor shaft is radially surrounded by the cooling fin(s) of the bearing flange. This provides the advantage that improved cooling is achieved and the air flow can be directed in the axial direction.

[0022] In an alternative advantageous embodiment, one or more cooling fins on the bearing flange protrude radially into the interior area radially surrounded by the bearing flange, in particular directed radially inward. This is advantageous in that improved cooling is achieved and the air flow is also guided more effectively.

[0023] In a preferred design, the bearing flange is made of aluminum. This provides the advantage of improved cooling.

[0024] In an advantageous embodiment, axially directed cooling fins protrude from the outside of the bearing flange, aligned parallel to the cooling fins formed on the stator housing. This is advantageous because the airflow path of the axially directed cooling fins can be extended, thus providing an axially directed airflow to the outside of the bearing flange and a circumferentially directed airflow to the inside. These two airflows are thus aligned crosswise and / or transversely to each other.

[0025] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0026] The invention will now be explained in more detail using schematic illustrations:

[0027] Figure 1 shows an oblique view of the electric motor according to the invention.

[0028] Figure 2 shows the electric motor in a partially cut-away side view.

[0029] In Figure 3, a bearing flange 6 of the electric motor is shown in an oblique view, with a fan 3 connected to the bearing flange 6.

[0030] In Figure 4, the bearing flange 6 is shown in an oblique view.

[0031] In Figure 5, the fan 3 is shown in an oblique view.

[0032] As shown in the figures, the electric motor has a stator housing on which axially extending cooling fins 7 running parallel to one another are formed.

[0033] A first bearing flange 6 is attached to the first axial end region of the stator housing, in which a bearing 20 is accommodated for the rotatable mounting of the rotor shaft 4 of the electric motor.

[0034] The fan 3 is mounted on the bearing flange 6 and connected to it. For this purpose, a protruding collar region 8 is formed on the housing of the fan 3, which rests against a connecting surface 40 and is preferably secured by means of screws extending through the collar region, which are screwed into threaded holes arranged in a flat connecting surface, and whose screw heads press the collar region 8 against the connecting surface.

[0035] On the side of the stator housing facing away from the bearing flange 6, a bearing shield is arranged to accommodate a further bearing of the rotor shaft 4. In addition, a second fan impeller is connected to the rotor shaft 4 in a rotationally fixed manner and surrounded by a fan cover 1. The air flow conveyed by the second fan impeller exits between the stator housing and the fan cover 1 in such a way that the air flow is specifically directed onto the cooling fins 7 and thus flows along them. The fan 3 is preferably designed as a radial fan, in particular wherein the air flow conveyed by the fan 3 exits the fan 3 essentially tangentially to the radially outer circumference of the fan blades conveying the air flow and enters an interior region of the bearing flange 20 through a recess 41 which is radially continuous with respect to the axis of rotation of the rotor shaft 4 of the electric motor.

[0036] From there, the air flow is led out to the environment through a second radially continuous recess in the bearing flange 6.

[0037] The air flow thus enters the bearing flange 3 in a radial direction relative to the axis of rotation of the rotor shaft 4 and also again through the second recess 5

[0038] The second recess 5 is preferably diametrically opposite the first recess 41. In particular, the circumferential angular range covered by the second recess 5 in the circumferential direction encompasses an angular position that differs by 180° from an angular position encompassed by the first recess 41.

[0039] The fan housing of the fan 3 has a collar 8, which rests on a flat connecting surface of the bearing flange 6 and is fastened by means of screws.

[0040] A terminal box 2 is located on the stator housing, into which electrical supply lines are routed through cable glands. An electrical cable for supplying the fan 3 is also routed through a cable gland into the interior of the terminal box.

[0041] The area covered by the terminal box 2 in the circumferential direction relative to the axis of rotation of the rotor shaft 4 comprises the circumferential angular area covered by the fan 3.

[0042] Furthermore, the area covered by the fan 3 in the axial direction overlaps both the area covered by the bearing flange 6 in the axial direction and the area covered by the stator housing in the axial direction. Thus, the fan requires no additional axial length. The bearing flange 6 is connected to the stator housing at its first axial end region and is or can be connected to a gear housing at its other axial end region.

[0043] Preferably, the bearing flange is formed with a square flange on its end face facing the stator housing and with a round flange on its side axially remote from the stator housing, in particular which is connectable or connected to the gear housing.

[0044] The rotor shaft 4 protrudes through the bearing flange 6. Radially between the rotor shaft 4 and the bearing flange is a clear interior space into which the air flow conveyed by the fan 3 flows through the recess 41. The air flow flowing from the interior space into the environment passes through the recess 5 into the environment.

[0045] However, since an air flow is also conveyed by the second fan wheel along the cooling fins 7 in the axial direction towards the bearing flange 6, whereby this air flow hits the bearing flange 6 after the cooling fins 6, the bearing flange 6 is cooled by an air flow on both its outside and its inside.

[0046] It is also important that if fan 3 or the airflow delivered by the second fan wheel fails, one of the two airflows remains active. The cooling of bearing flange 6 is thus designed safely, in particular according to a higher safety category.

[0047] The normal direction of the flat connecting surface 40 is oriented perpendicular to the rotational axis of the rotor shaft 4. The circumferential angular range covered by the connecting surface 40 in the circumferential direction relative to the rotational axis of the rotor shaft 4 overlaps with the circumferential angular range covered by the terminal box 2 in the circumferential direction.

[0048] In particular, the installation space occupied by the terminal box is thus sufficient to encompass the fan 3, except in the radial direction, when this installation space is extended axially. This is because the fan 3 protrudes beyond the terminal box 2 in the radial direction. The flat connecting surface 40 is shaped like a hollow rectangle and interrupts the cylindrical outer circumference of the bearing flange 6 in the circumferential angular area covered by the connecting surface.

[0049] After connecting the gearbox housing to the bearing flange 6 on the side facing away from the stator housing, the interior area radially surrounded by the bearing flange 6 is axially bounded on the one hand by the gearbox and, on the side facing away from the gearbox, by the bearing accommodated in the bearing flange 6 and the associated sealing arrangement. The sealing arrangement comprises a shaft seal accommodated in a flange part, wherein the flange part is connected to the bearing flange and arranged in the interior area.

[0050] The axis of rotation of the rotor shaft 4 is preferably aligned perpendicular to the axis of rotation of the fan 3, which is, however, preferably aligned parallel to the flat connecting surface 40.

[0051] The recess 5 is arranged on the circumference of the bearing flange 6 diametrically opposite the recess 41, so that when the bearing flange is vertically aligned, i.e., when the bearing flange 6 is spatially oriented such that the recess 41 is arranged vertically above the recess 5. In this way, the penetration of rain into the interior area can be prevented, and any water that has penetrated flows through the recess 5 into the environment.

[0052] In further embodiments according to the invention, another device, in particular a machine, is connected to the bearing flange instead of a gear. For example, a wheel, in particular a sprocket, is pushed onto the rotor shaft 4 and connected in a rotationally fixed manner, in particular by means of a key connection. The interior area radially surrounding the bearing flange 6 opens directly into the oil-filled gear interior, in which the meshing gear parts of the gear are arranged. A driving pinion is connected in a rotationally fixed manner, in particular by means of a key connection, to the rotor shaft 4 and engages a gear part of the gear. List of Reference Symbols

[0053] 1 Fan cover 2 Terminal box

[0054] 3 fans, especially radial fans

[0055] 4 Rotor shaft

[0056] 5 radial continuous recess

[0057] 6 Bearing flange 7 Cooling fin

[0058] 8 collars

[0059] 20 warehouses

[0060] 40 connecting surface

[0061] 41 radial continuous recess

Claims

Patent claims:

1. Electric motor with a fan, the electric motor having a stator housing to which a bearing flange of the electric motor is connected, characterized in that a fan is connected to the bearing flange, in which fan a bearing, in particular an outer ring of a bearing, is received for rotatably supporting the rotor shaft of the electric motor, the bearing flange having a first recess which is radially continuous with respect to the axis of rotation of the rotor shaft and through which the air flow conveyed by the fan flows into an interior region radially surrounded by the bearing flange, the bearing flange having a second recess which is spaced apart from the first recess in the circumferential direction, through which the interior region opens into the outer environment of the bearing flange and / or through which the air flow exits from the interior region into the outer environment of the bearing flange.

2. Electric motor according to claim 1, characterized in that a fan housing of the fan has a collar projecting from the fan housing, which is connected to a flat connecting surface of the bearing flange.

3. Electric motor according to one of the preceding claims, characterized in that on the side of the stator housing facing away from the bearing flange, a bearing plate for receiving a further bearing of the rotor shaft is arranged, wherein on the side of the stator housing facing away from the bearing flange, a second fan wheel is connected to the rotor shaft in a rotationally fixed manner and is radially surrounded by a fan cover detachably connected to the bearing plate, wherein the air flow conveyed by the second fan wheel flows along cooling fins formed on the outside of the stator housing in the axial direction, in particular parallel to the axis of rotation of the rotor shaft, and in particular then flows along the bearing flange, in particular wherein the fan cover has grille openings passing through the fan cover on its axial end face facing away from the bearing flange, in particular for inflow, in particular wherein the cooling fins are spaced apart from one another in the circumferential direction,in particular wherein the axial, radial and / or circumferential direction is related to the axis of rotation of the rotor shaft., 4. Electric motor according to one of the preceding claims, characterized in that a terminal box is mounted on the stator housing and connected to the stator housing.

5. Electric motor according to one of the preceding claims, characterized in that the circumferential angular range covered by the terminal box in the circumferential direction comprises the circumferential angular range covered by the fan.

6. Electric motor according to one of the preceding claims, characterized in that the terminal box is spaced from the fan in the axial direction.

7. Electric motor according to one of the preceding claims, characterized in that the radial distance area covered by the fan, in particular by the fan housing, comprises the radial distance area covered by the terminal box.

8. Electric motor according to one of the preceding claims, characterized in that in the interior region radially surrounded by the bearing flange, a flange part is detachably connected to the bearing flange, wherein the rotor shaft projects through a recess of the flange part, wherein a shaft sealing ring is received in the flange part, which seals towards the rotor shaft, in particular whose sealing lip therefore runs on the rotor shaft, in particular wherein the flange part is arranged on the side of the bearing flange axially facing away from the stator housing and / or the bearing receptacle of the bearing formed in the bearing flange.

9. Electric motor according to one of the preceding claims, characterized in that the bearing flange is formed as a square flange on its side facing the stator housing and as a round flange on its side facing away from the stator housing, in particular for connection to a device to be driven, in particular a gearbox.

10. Electric motor according to one of the preceding claims, characterized in that the bearing flange has a cylindrical outer surface in the region covered by the connecting surface in the axial direction, which is interrupted in the circumferential angular region covered by the connecting surface in the circumferential direction, in particular for shaping the connecting surface.

11. Electric motor according to one of the preceding claims, characterized in that on the bearing flange one or more cooling fins protrude in the axial direction into the interior region radially surrounded by the bearing flange, in particular and the flange part connected to the bearing flange and receiving a shaft sealing ring sealing towards the rotor shaft is radially surrounded by the cooling fin(s) of the bearing flange, or that on the bearing flange one or more cooling fins protrude in the radial direction into the interior region radially surrounded by the bearing flange, in particular directed radially inwards.

12. Electric motor according to one of the preceding claims, characterized in that the bearing flange is made of aluminum.

13. Electric motor according to one of the preceding claims, characterized in that axially directed cooling fins protrude on the outside of the bearing flange and are aligned parallel to the cooling fins formed on the stator housing.

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