Device for guiding cooling air on a motor accessory for a fan motor

Abstract

The invention relates to a device for conducting cooling air to a motor receptacle for a fan motor, in particular an electric fan motor or a motor with fan forced cooling. According to the invention, the device has a plurality of cutouts (13), which extend from an outer circumference (6) of the annular motor receptacle (1) to an inner circumference (4) of the annular motor receptacle (1) at an end face (2) of the annular motor receptacle (1), for conducting a part of an air flow generated by the fan (14) at the outer circumference (6) of the annular motor receptacle (1) to the ring opening cross-section (12). The invention also relates to a correspondingly designed annular motor receptacle (1).

Description

Technical Field

[0001] The invention relates to a device for guiding cooling air at a motor housing for a fan motor, in particular an electric fan motor or a motor with forced fan cooling, in order to achieve improved cooling efficiency. The invention also relates to an annular motor housing, at which a corresponding device is formed. Background Art

[0002] Due to its high efficiency of more than 90 percent, electric motors work very efficiently. However, part of the delivered electrical energy is converted into heat during operation, and in order to avoid overheating, the heat must be discharged as continuously as possible. For this reason, the motor housing of the electric motor has a cooling body in the form of cooling fins, which are usually arranged at the outer circumference while forming an outwardly open flow channel for cooling air, so as to achieve an increase in the area for discharging heat to the ambient medium. The motor housing has a cylindrical shape that is usually favorable for flow, and the shape is limited by two opposite end sides. In air-cooled electric motors, the cooling power can be supported by forced cooling using a fan or end impeller driven by the electric motor. An air flow is generated by the rotation of the fan or end impeller, and the air flow is partially guided along the cooling fins of the motor housing through the flow channel formed by the cooling fins. Therefore, the heat generated by the electric motor can be discharged via the motor housing using the air flow generated by the fan or end impeller.

[0003] However, cooling by means of the generated air flow at the end side of the motor housing has proven difficult, since the air flow is essentially guided along the outer circumference of the motor housing and at least one end side of the motor housing is covered by a motor receptacle, to which the motor housing is fastened. In addition, it is disadvantageous that the flow along the cooling ribs is adversely affected by the full-surface fastening of the end side of the motor housing to such a motor receptacle, since the air inlet or air outlet of the flow channel formed between the cooling ribs of the motor housing is also covered by the motor receptacle. For the reasons mentioned, the motor receptacle, in particular for the ventilator motor, can be designed in an annular manner, so that when the end side of the electric motor is fastened in the region of the annular opening cross section of the motor receptacle, at least a part of the surface of the end side of the electric motor remains free and thus accessible to the cooling air flow. The dimensions of the annular motor receptacle are advantageously selected here so that the dimensions cover the smallest possible surface of the end side of the electric motor or the electric motor housing, so that the air inlet or air outlet remains at least partially free of the flow channel formed between the cooling ribs.

[0004] Such an annular motor receptacle for a fan motor, in particular in vehicle fans, such as those used, for example, for motor cooling or for air conditioning of the vehicle interior, is expediently formed in a flow-through retaining structure. A grid or spokes are used as retaining structure in order to influence the air flow generated by the fan as little as possible.

[0005] It has been found that the cooling capacity of a motor housing fastened at one end on the end face side of the end face is still insufficient despite the annular design of the motor housing receptacle, since the air flow in the region of the ring opening cross section of the annular motor receptacle is low. Summary of the invention

[0006] The object underlying the present invention is therefore to provide a device with which the cooling capacity of a fan motor or electric motor fastened at the end to a motor receptacle and having forced fan cooling can be improved.

[0007] This object is achieved by a device having the features of claim 1 and an annular motor receptacle having the features of claim 14. Developments are given in the dependent claims.

[0008] In order to achieve the above object, a device for guiding cooling air to an annular motor receiving portion for a fan motor is proposed. The present invention is particularly provided for a fan motor, which has cooling fins extending outwardly arranged on the outside of its motor housing in the following manner: the arrangement between the cooling fins constitutes a channel for cooling air that is open to the outside, and the cooling air inlet of the channel is oriented toward the end side of the motor housing of the fan motor. The device according to the present invention requires an annular motor receiving portion, on which the motor housing of the fan motor can be fastened with the end side of the motor housing, wherein the ring opening cross-sectional dimensions of the annular motor receiving portion are determined so that the cooling air inlet of the channel for cooling air is at least partially inside the ring opening cross-sectional area. The device has a plurality of recesses extending from the outer circumference of the annular motor receiving portion toward the inner circumference of the annular motor receiving portion at the end side of the annular motor receiving portion, for guiding a portion of the air flow generated by the fan at the outer circumference of the annular motor receiving portion to the ring opening cross-sectional area. Preferably, the recesses are evenly distributed.

[0009] Advantageously, the recess in the end face at the end side of the annular motor receiving portion forms an air guiding element in the form of an air guiding channel open to the outside, and the air guiding channel is geometrically designed so that the air guiding channel guides the air flow generated by the fan by the rotation of the fan at the outer circumference of the annular motor receiving portion along the recess from the outer circumference of the annular motor receiving portion to the inner circumference of the annular motor receiving portion, that is, to the annular opening cross section, so that the conveyed cooling air can reach the cooling air channel for the motor housing from the annular opening cross section through the cooling air inlet. In this way, improved utilization of the cooling air flow and improved cooling power at the end side can be achieved. The recess is a recess that is formed in the end face of the annular motor receiving portion in the axial direction of the fan motor fastened to the annular motor receiving portion at the end side according to a design. Here, the recess has an opening at the radial outer circumference of the annular motor receiving portion, which can also be called an air inlet opening, wherein the opening of the recess is formed at the radial inner circumference of the annular motor receiving portion, which can also be called an exhaust opening. The air inlet opening and the air outlet opening are each connected to one another via a recess, wherein a flow path for cooling air is formed between the air inlet opening and the air outlet opening along the recess connecting the openings. The flow path of the cooling air is predetermined by the extent of the recess, wherein the length of the flow path is predetermined by the geometry of the recess. The recess can also be referred to as an air guide element or an air guide channel.

[0010] The ring opening cross section of the annular motor receptacle is preferably circular. However, designs of annular motor receptacles can also be provided in which the ring opening cross section has another shape that is matched to the geometry of the end face of the motor housing.

[0011] In the sense of the invention, fan motors are motors which are fastened at the end face to a motor receptacle and which directly drive an axial impeller or end impeller, thereby generating an air flow.

[0012] In the sense of the invention, the motor housing has a cylindrical shape delimited by two opposite end faces, on whose side surfaces cooling ribs with cooling channels open to the outside are formed. The motor housing is provided for fastening at its end faces to an annular motor receptacle.

[0013] The geometrical design of the cutouts can be arranged such that the length of each cutout extending from the outer circumference to the inner circumference of the annular motor receptacle is greater than the radial spacing between the outer circumference and the inner circumference of the annular motor receptacle. This means that the cutouts preferably do not extend on a straight line on the shortest path from the outer circumference to the inner circumference of the annular motor receptacle, but are formed in a curved, inclined manner or in a manner following the arch of the end face. In other words, the flow path of the cutout is longer than the radial thickness of the annular motor receptacle.

[0014] The extension of the recesses can also imitate a specific track curve in the form of a predetermined trajectory. Thus, the recesses can follow a predetermined trajectory from the outer circumference of the annular motor receptacle to the inner circumference of the annular motor receptacle. The extension of several recesses from the outer circumference to the inner circumference of the annular motor receptacle can be identical. However, it can also be provided that the recesses alternately follow the extension of different trajectories or imitate the extension of different trajectories.

[0015] The extension of the recess is oriented along the direction of rotation of the fan. Accordingly, when the fan rotates clockwise, the extension of the recess can be oriented clockwise, wherein the blades of the fan generate an axial air flow which is sucked in from the end side of the annular motor receptacle.

[0016] According to a further embodiment of the device according to the invention, the recess can be designed in the form of a helical line, the origin of which lies at the center point of the annular motor receptacle.

[0017] In all embodiments of the recess formed in the annular motor receptacle, it can be provided that the recess has a depression which is formed in the form of a groove transversely to the extent of the recess. The depression has an influence on the flow of cooling air along the air guide channel formed by the recess. Preferably, the recess is formed in the form of a groove transversely to the extent of the recess.

[0018] Preferably, the groove can be formed in the course of the recess toward the inner circumference of the annular motor receptacle in the last quarter, preferably the last fifth, of the flow path.

[0019] Advantageously, the recess can be rounded at the transition to the end face of the annular motor receptacle.A specific radius can be provided which follows the dimensions of the entire device.

[0020] Furthermore, radial transitions at the outer circumference and the inner circumference of the annular motor receptacle can be rounded.

[0021] Furthermore, it can be provided that the recess has a narrowing in the direction of the cooling air flow along the extension of the recess. Advantageously, the cooling air flow is accelerated in the direction of the ring opening cross section by the narrowing in the extension of the recess, thereby ultimately accelerating the flow speed along the channel for cooling air at the motor housing.

[0022] According to a particularly preferred embodiment of the device according to the invention, the recesses are arranged so that they open into cooling air inlets between two cooling ribs of the motor housing at the inner circumference of the annular motor receptacle. In this way, it is ensured that the cooling air guided along the recesses reaches directly through the radial cooling air outlets into the channels for cooling air formed by the two cooling ribs. The number of recesses formed in the end face of the annular motor receptacle can expediently correspond to the number of channels for cooling air on the motor housing.

[0023] According to one configuration, the cutouts can each have the same depth and the same width, wherein the depth and the width of the cutouts are dimensioned according to the size of the motor.

[0024] The annular motor receptacle of the device according to the invention can have through-holes through which screws are screwed into the motor housing of the fan motor in order to fasten the fan motor to the annular motor receptacle. The annular motor receptacle preferably has at least three through-holes for screwing the fan motor housing. Other fastening methods are conceivable, such as clamping fastening, in which a clamping connection is formed between the flange formed by the annular motor receptacle and a flange formed on the motor housing.

[0025] According to another advantageous embodiment of the device according to the invention, the end face of the annular motor receptacle which is provided with the recess can be curved, preferably convexly curved. It can be provided that the extent of the recess with the flow path of the recess follows the curvature. In this embodiment, the depth of the recess is the same at every location along the extent of the recess with respect to the curved end face of the annular motor receptacle.

[0026] Furthermore, an annular motor receptacle is an integral part of the invention, and the device according to the invention according to one or more of the above-mentioned embodiments has the annular motor receptacle. This includes an annular motor receptacle, at the end side of which a recess for guiding cooling air is formed. The annular motor receptacle can have different annular shapes. The annular shape of the motor receptacle is not limited to a circular ring shape.

[0027] The annular motor receptacle can be formed as a component of a holding structure with low air resistance. The holding structure with low air resistance is preferably a grid or spoke structure, in the center of which the annular motor receptacle is formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further details, features and advantages of the design of the present invention are apparent from the following description of exemplary embodiments with reference to the accompanying drawings. The accompanying drawings show:

[0029] Figure 1 A schematic diagram of an annular motor receptacle known from the prior art for receiving and holding a fan motor is shown,

[0030] Figure 2 shows an annular motor receptacle for a fan motor connected to a flat holding structure,

[0031] Figure 3 A detailed view of an exemplary embodiment of the device according to the invention for directing cooling air to an annular motor receptacle for a fan motor,

[0032] Figure 4 A further detailed illustration of the device according to the invention for directing cooling air to an annular motor receptacle for a fan motor is shown, and

[0033] Figure 5 A schematic diagram shows a further exemplary embodiment of a device according to the invention for directing cooling air to a motor receptacle for a fan motor. DETAILED DESCRIPTION

[0034] Figure 1 A schematic diagram of an annular motor receiving portion 1 known from the prior art for receiving and holding a fan motor is shown. The end side 2 of the annular motor receiving portion 1 is smooth and slightly arched outward, that is, convexly arched. The fan motor is fastened by means of bolts (not shown), which are guided and screwed into the end side of the fan motor housing through the through-holes 3 formed in the annular motor receiving portion 1. The through-holes 3 are formed as molded portions in the material of the annular motor receiving portion 1 and are evenly distributed on the inner circumference 4 of the annular motor receiving portion 1. From the end side 2, the through-holes 3 have countersunk holes so that the bolt heads are sunk in the installed state. The fan motor is fastened at the back side of the annular motor receiving portion 1, that is, at the end side of the annular motor receiving portion 1 opposite to the end side 2.

[0035] Figure 2 An annular motor receptacle 1 for a fan motor is shown, connected to a flat retaining structure 5 , as it can be inserted, for example, in a vehicle. Figure 2For illustrating the positioning of the annular motor receptacle 1 in the holding structure 5. In the example shown, the annular motor receptacle 1 is arranged in the center of the holding structure 5 and is held by radial spokes 5.1 of the holding structure 5. In this case, the radial spokes 5.1 are fastened to the outer circumference 6 of the annular motor receptacle 1. In this way, the annular motor receptacle 1 can accommodate a fan motor in order to generate an air flow orthogonal to the holding structure 5. Figure 2 The embodiment of the annular motor receptacle shown in FIG. 1 comprises the device according to the invention, which is connected to the fan motor in a Figure 3 and Figure 4 Elaborated in detail.

[0036] Figure 3 A detailed view of an embodiment of a device according to the invention for guiding cooling air to an annular motor receptacle 1 for a fan motor 7 is shown, the fan motor being fastened with an end face 8 on the back side of the annular motor receptacle 1. Bolts 9 are used as fastening means, which are screwed into the fan motor housing guided through the through-holes 3. The fan motor 7 has cooling ribs 10 extending outwards on the outside of its motor housing, which are arranged as follows: the arrangement between the cooling ribs 10 forms an outwardly open channel for cooling air, the cooling air inlet 11 of which is oriented toward the end face of the motor housing. Here, the annular motor receptacle 1 has an annular opening cross section 12, which is limited by the inner circumference 4 and is dimensioned so that the cooling air inlet 11 of the channel for cooling air of the fan motor 7 is at least partially located within the annular opening cross section 12. The device according to the invention has a plurality of recesses 13 extending from the outer circumference 6 of the annular motor receptacle 1 toward the inner circumference 4 of the annular motor receptacle 1 at the end face 2 of the annular motor receptacle 1. The recess 13 serves to guide a portion of the air flow generated by the fan 14 at the outer circumference 6 of the annular motor receptacle 1 toward the annular opening cross section 12 .

[0037] Figure 4 Shown in Figure 2 and Figure 3Detailed depiction of the annular motor receptacle 1 shown in FIG. 1 , at which the device according to the invention is formed. According to the invention, the annular motor receptacle 1 is dimensioned in comparison with the dimensions of the fan motor housing so that the cooling air inlet 11 is located within the ring opening cross section 12 of the annular motor receptacle 1. According to the invention, a recess 13 for guiding air formed at the end side 2 in the form of a recess in the end face of the end side 2 extends from the outer circumference 6 of the annular motor receptacle 1 to the inner circumference 4 of the annular motor receptacle 1, wherein the recess 13 is arranged evenly distributed. The arrangement of the recess 13 or the positioning of the annular motor receptacle 1 and the fan motor 7 can be provided, wherein the recess 13 leads to the cooling air inlet 11 at the inner circumference 4, so that the air guided through the recess 13 can directly reach the cooling air inlet 11. The extension of the recess 13 is formed corresponding to the direction of rotation of the fan 14. Here, the extension of the recess is not linear, but follows the track curve, thereby producing an arc-shaped extension. The direction of rotation of the fan 14 generates an air flow which is sucked into the end face 2 of the annular motor receptacle 1 which is provided with the recess 13. Due to the arrangement and orientation of the recess 13, at least a portion of the air sucked in by the fan 14 during operation is guided in the direction of the annular opening cross section 12, so that the sucked in air can be guided through the cooling air inlet 11 into the channel for cooling air of the fan motor 7. As a result, an improvement in the cooling air flow in the axial direction to the motor housing of the fan motor 7 is produced, and in addition an improved cooling performance is achieved at the end face 8 of the fan motor 7.

[0038] The cutout 13 has a recess which is formed transversely to the extent of the cutout 13 in the form of a groove 15. Furthermore, the transition of the cutout 13 at the end face 2 is rounded. In the present exemplary embodiment, the end face of the end face 2 of the annular motor receptacle 1 is convex, i.e., curved outwards. The extent of the cutout 13 follows the convex design of the end face of the annular motor receptacle 1. Therefore, the extent of the cutout 13 is also curved.

[0039] Figure 5 A further embodiment of a device according to the invention for guiding cooling air to an annular motor receptacle 1 of a fan motor 7 (not shown) is shown, wherein the annular motor receptacle 1 is held integrally in a grid structure 16 which additionally has reinforcing bars. The annular motor receptacle 1 has three fastening points 17 to which a fan motor 7 (not shown here) can be fastened.

[0040] Reference numerals list

[0041] 1 Annular motor housing

[0042] 2 End side

[0043] 3. Perforation

[0044] 4 Inner ring

[0045] 5. Maintain structure

[0046] 5.1 Radial spokes

[0047] 6 Outer ring

[0048] 7 Fan motor

[0049] 8 End side of motor housing

[0050] 9 Bolts

[0051] 10 Cooling fins

[0052] 11 Cooling air inlet

[0053] 12 ring opening cross section

[0054] 13 blank space

[0055] 14 Ventilator

[0056] 15 Grooves

[0057] 16 grid structure

[0058] 17 fastening points

Claims

1. A device for guiding cooling air to an annular motor receptacle (1) for a fan motor (7), the fan motor having, on the outside of its motor housing, outwardly extending cooling ribs (10) arranged in the following manner: the arrangement forms an outwardly open channel for cooling air between the cooling ribs (10), the cooling air inlet (11) of the channel being oriented toward an end side (8) of the motor housing, the motor housing being fastened to the annular motor receptacle (1) with the end side (8), the annular opening of the annular motor receptacle (1) being lateral to the end side (8) of the motor housing. The cross-section (12) is dimensioned so that a cooling air inlet (11) of the channel for cooling air is at least partially located within the annular opening cross section (12), and the device has a plurality of recesses (13) extending from the outer circumference (6) of the annular motor receptacle (1) toward the inner circumference (4) of the annular motor receptacle (1) at the end side (2) of the annular motor receptacle (1) for guiding a portion of the air flow generated by a ventilator (14) at the outer circumference (6) of the annular motor receptacle (1) to the annular opening cross section (12).

2. The device according to claim 1, characterized in that The extent of the recess (13) is greater than the radial distance between the outer circumference (6) and the inner circumference (4) of the annular motor receptacle (1).

3. The device according to claim 1 or 2, characterized in that The recess (13) follows a predetermined path from the outer circumference (6) of the annular motor receptacle (1) to the inner circumference (4) of the annular motor receptacle (1).

4. The device according to any one of the preceding claims, characterized in that The extent of the recess (13) is oriented in the direction of rotation of the fan.

5. The device according to any one of the preceding claims, characterized in that The recess (13) is designed in the form of a helical line, the origin of which is located at the center point of the annular motor receptacle (1).

6. The device according to any one of the preceding claims, characterized in that The recess (13) has a depression which is designed in the form of a groove (15) transversely to the extent of the recess.

7. Device according to the preceding claim, characterized in that The groove (15) is formed in the last quarter, preferably the last fifth, of the inner circumference (4) of the annular motor receptacle (1) in the extent of the recess (13).

8. The device according to any one of the preceding claims, characterized in that The recess (13) is rounded at the transition to the end face of the end side (2).

9. The device according to any one of the preceding claims, characterized in that The recess (13) has a respective constriction along the extent of the recess.

10. The device according to any one of the preceding claims, characterized in that The recesses (13) are arranged such that they open at the inner circumference (4) of the annular motor receptacle (1) into cooling air inlets (11) between two cooling ribs (10) of the motor housing.

11. The device according to any one of the preceding claims, characterized in that The number of the recesses (13) corresponds to the number of the channels for cooling air.

12. The device according to any one of the preceding claims, characterized in that All recesses ( 13 ) have the same depth and the same width.

13. The device according to any one of the preceding claims, characterized in that The end face of the end face (2) of the annular motor receptacle (1) which forms the recess (13) is curved, preferably convexly curved.

14. An annular motor receptacle (1) for receiving and fastening a fan motor (7), comprising a device for guiding cooling air according to claims 1 to 13.

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