WO2015075103A1

WO2015075103A1 - Diagonal or axial fan comprising a cooled drive unit

Info

Publication number: WO2015075103A1
Application number: PCT/EP2014/075084
Authority: WO
Inventors: Peter Ragg
Original assignee: Ebm-Papst St. Georgen Gmbh & Co. Kg
Priority date: 2013-11-22
Filing date: 2014-11-20
Publication date: 2015-05-28
Also published as: DE102013112922A1; DE112014005327A5

Abstract

A diagonal or axial fan (100) comprises an air intake side (108) and an air discharge side (109) as well as an external rotor motor (150) that is mounted at least in part on a support tube (172) and drives an impeller (14) which is designed to allow, during operation of the fan, a cooling air flow (104) to be generated at least for cooling the external rotor motor (150), said cooling air flow being caused at least in part by negative pressure and flowing from the air discharge side (109) towards the air intake side (108).

Description

DIAGONAL OR AXIAL FAN WITH COOLED DRIVE

The invention relates to a diagonal or axial fan with a fan, which is assigned to its drive an external rotor motor.

In such diagonal or axial fans reach associated

External rotor motors in operation speeds of, for example, up to 5,000 rpm, with smaller engines of this type often have a capacity of less than 100 W. Nevertheless, these external rotor motors can become very hot during operation, so that associated bearing elements, which serve for rotatably supporting corresponding outer rotors of the external rotor motors, can be heated comparatively strongly. This can lead to a reduction of a respective grease service life of lubricants of the bearing elements or to their thermal destruction and thus limit or reduce the life of such diagonal or axial fan.

To such a reduction of a respective grease life of

To prevent lubricants of the bearing elements or their thermal destruction, in conventional diagonal or axial fans, a cooling air flow is generated and, for. performed in the region between the bearing tubes and the external rotor motors in an associated main conveying direction. In this case, this main conveying direction points from an air inlet side to an air outlet side of a fan housing assigned to the respective fan.

In such diagonal or axial fans, the problem is that there is a reversal point with a corresponding flow through the external rotor motor by the cooling air flow: In free-blowing operation, ie without back pressure, the external rotor motor is flowed through, as described above in the main conveying direction of the fan from a certain back pressure on the air outlet side, the direction of the cooling air flow turns around. This reversal point is in most Cases in the intended working range of the fan. This has the consequence that the diagonal or axial fan can again heat strongly when reaching the reversal point due to exposure of the cooling air flow, which in turn lead to a reduction of a respective grease service life of lubricants of the bearing elements or their thermal destruction and thus the

Limit life of such diagonal or axial fan or can reduce.

It is therefore an object of the invention to provide a new diagonal or axial fan. This object is solved by the subject matter of the independent claim. Preferred embodiments are subject of the dependent claims.

In particular, the object of the present invention is achieved by a diagonal or axial fan according to claim 1. In this diagonal or axial fan, an extension of the service life is achieved by simple means, since a respective generated cooling air flow maintains its direction under all operating conditions, namely opposite to the main conveying direction of the fan, so that the

External rotor motor and thus the bearing tube and associated bearing elements are safely cooled under all operating conditions.

Further details and advantageous developments of the invention will become apparent from the hereinafter described and illustrated in the drawings, to be understood in any way as limiting the invention

Embodiments. It shows:

1 is a sectional view of a diagonal or axial fan with a fan according to the invention,

2 is a perspective view of the diagonal or axial fan of FIG. 1 in an exploded view,

3 is a sectional view of the fan of Fig. 1 and Fig. 2, taken along a section line III-III of Fig. 4, 4 is a plan view of an underside of the fan of Fig. 1 to Fig. 3,

5 is a partially sectioned plan view of the underside of the fan of Fig. 1 to Fig. 4,

6 is a detail of the sectional view of Fig. 3,

7 is a perspective sectional view of the fan of Fig. 1 to Fig. 4,

8 is a detail of the sectional view of Fig. 7,

9 is a plan view of an upper side of the fan wheel of Fig. 1 to Fig. 3,

10 is a side view of the fan of Fig. 1 to Fig. 3,

1 is a perspective view of the fan of Fig. 1 to Fig. 3,

Fig. 12 is a Messdiagrannnn Betnebparameters diagonal or axial fan of Fig. 1, and

13 is a measurement diagram of operating parameters of the diagonal or axial fan of Fig. 1 with a conventional fan.

In the following description, the terms left, right, up and down refer to the respective drawing figure and depending on a selected orientation (portrait or landscape) of a

Drawing figure to the next vary. Identical or equivalent parts are denoted in the various figures with the same reference numerals and

usually described only once.

1 shows a fan 100 provided with a fan housing 110 having a fan wheel 140, which according to one embodiment is designed in the manner of a diagonal or axial fan and which preferably commutes electronically

Drive motor 150 for rotational drive of the fan 140 has. The drive motor 150 is preferably designed in the manner of an external rotor motor and has an inner stator 130, an outer rotor 160 formed by the fan wheel 140, and a printed circuit board 176, which is equipped, for example, with electronic components required for controlling the drive motor 150.

The inner stator 130 is separated from the outer rotor 160 by a magnetic air gap, so that during operation of the fan 100 with the outer rotor 160th

to be able to interact but still allow rotation of the outer rotor 160. For this purpose, the fan wheel 140 forming the outer rotor 160 has a cup-shaped carrier 182, which is preferably designed as a shaped piece made of plastic, and on which a shaft 149, also referred to as a rotor shaft, is secured against rotation. The cup-shaped carrier 182 preferably has a bottom wall 184 and an annular side wall 188 which has an open end on the side facing away from the bottom wall 184 side.

The cup-shaped carrier 182 defines on its inner side an inner space 192, which is shown in FIGS. 3, 7 and 8, wherein it is shown dotted in FIG. 3 for illustration. Due to the central rotor shaft 149, the interior 192 is preferably annular.

On the circuit board 176, preferably on the side facing away from the inner stator 130 side, illustratively at least two thermocouples 198, 199th

arranged, which serve here only for the detection of operating parameters of the fan 100 for experimental purposes and thus have only optional character, so that can be dispensed with a use of the fan 100 in production suitable for their use.

The fan housing 110 preferably forms an air inlet side 108 and a

Air outlet side 109 and is provided with a flange 170, on which a bearing tube 172 is arranged. This flange 170 is connected via a plurality of connecting webs 1 17 with the fan housing 1 10, wherein for the sake of simplicity and clarity of the drawing, only a single connecting web is designated by the reference numeral 179. For attachment to or in one external device, the fan housing 1 10 illustratively fastening means 1 12, eg mounting holes, on.

The bearing tube 172 is preferably formed integrally with the flange 170 and has a bearing tube wall 122, which preferably has a central

Lagerrohrausnehmung 124 forms for receiving a bearing assembly 131. This has one or more bearing elements 173, 174, which are preferably formed by at least two rolling or ball bearings 173, 174. But there are also sintered bearings 173, 174 possible. On the bearing tube 172, the inner stator 130 is at least partially arranged, in particular rotationally fixed and preferably at least substantially centered, and preferably also the printed circuit board 176. For this purpose, the inner stator 130 has a central Innenstatorausnehmung 139, which is provided for mounting on the bearing tube wall 122.

The fan housing 1 10, the connecting webs 17, the flange 170 and the bearing tube 172 are preferably made of plastic, since plastic allows a favorable production and fine details. In high-performance electric motors, however, the parts mentioned are preferably formed partially or completely of metal, since metal on the one hand mechanically stable and on the other hand, the resulting heat in the electric motor can dissipate better than plastic.

A first fluid channel (cooling channel) 177 is provided on the fan wheel 140, and at least one second fluid channel (cooling channel) 171, 175 is provided in the area of the bearing tube 172 in order to support and improve cooling of the interior 192 by a fluid, in particular air or another gas is passed through the interior 192, as will be described in more detail below.

The inner stator 130 preferably has a laminated core 134 provided with a motor winding 132, which forms the central inner stator recess 139. In the area between the inner stator 130 and the central bearing tube recess 124, at least one second fluid channel 171, 175 is preferably formed. Illustratively, two second fluid channels 171, 175 are shown here. These second fluid channels 171, 175 preferably pass through the flange part 170 and extend in the region between the central inner stator recess 139 and the bearing tube wall 122 In this case, the second fluid channels 171, 175 extend preferably at least partially from the air outlet side 109 of the fan housing 110 in the central Innenstatorausnehmung 139 in the direction of the air inlet side 108 of the fan housing 1 10, preferably at least up to a region which is arranged on a side remote from the air outlet side 109 of the fan housing 1 10 side of the inner stator 130, particularly preferably in the interior 192nd

In addition to a fluid supply through the second fluid channels 171, 175 and a fluid supply from the free end of the annular side wall, which is on the pressure sides 181 ", 185" of the fan blades 181, 185, via the magnetic air gap into the interior 192 (FIG. 3) possible, this fluid flow does not flow through the bearing elements 173, 174 and therefore does not cool in this area.

Furthermore, the inner stator 130 preferably has fastening elements 138 for the rotationally fixed attachment of the inner stator 130 to the printed circuit board 176

Attachment of the Rotor Shaft 149, the cup-shaped support 182 preferably has a mounting portion 186, to which a metal part 107 is attached, in particular as an insert in the plastic injection molding, on which the rotor shaft 149th

is secured against rotation secured. This is preferably mounted rotatably about a rotation axis 141 in the bearing assembly 131.

On the annular side wall 188 is a plurality of fan blades 180 for generating a in a main conveying direction 105 of the fan 100 of the

Air inlet side 108 of the fan housing 1 10 to the air outlet side 109 through the fan housing 1 10 directed air flow 103 is arranged. Here, each of the plurality of fan blades 180 forms a pressure side facing the air outlet side 109 and a negative pressure side facing the air inlet side 108. Illustratively, only two of the plurality of fan blades 180 are visible, which are identified by the reference numerals 181, 185. These fan blades 181, 185 form by way of example pressure sides 181 "or 185" and vacuum sides 181 'or 185'. The bottom wall 184 of the cup-shaped support 182 preferably has a plurality of ribs 190 on its side 184 'facing the air outlet side 109 of the fan housing 110, of which only two are visible, which are identified by the reference numerals 191, 193. In addition, the forms

Bottom wall 184 on its side 184 'at least a first fluid channel, in particular by a corresponding arrangement of the plurality of ribs 190. Illustratively here is a single first fluid channel 177 visible. This one stands

Preferably, on the one hand with the interior 192 and thus with at least one of the second fluid channels 171, 175 in fluid communication, and he is on the other hand at least one at the cup-shaped support 182 in the bottom wall 184 formed Luftdurcht ttsöffnung in fluid communication with the negative pressure side of at least one fan blade. Here, a plurality of air passage openings 120 is preferably formed on the bottom wall 184.

It can also be said that the air passage openings 120, 178 formed in the area of the bottom wall 184 extend from the interior 192 directly to the negative pressure side of at least one fan blade 185.

Illustratively, the first fluid channel 177 communicates with the second fluid channel 175 in FIG

Fluid communication and via an air passage opening 178 in fluid communication with the negative pressure side 185 'of the fan blade 185. This serves to at least partially caused by negative pressure generation of a provided at least for cooling the external rotor motor 150 cooling air flow 104 from the air outlet side 109 during operation of the fan 100 at least over the second fluid channel 175, the first fluid channel 177 and the at least one air passage opening 178 for

Allow negative pressure side 185 '. In this case, during operation of the fan 100, the bottom wall 184 provided with the plurality of ribs 190 preferably forms a radial fan at least in regions in order to at least support the generation of the cooling air flow 104. The ribs 190 typically result in stiffening and reinforcement of the corresponding portion of the bottom wall 184, and therefore the ribs 190 may also be referred to as reinforcing ribs or stiffening ribs 190. The stiffening or reinforcement is particularly advantageous in the radially inner region, but also effective in the radially outer region when it extends into the radially outer region. For the radial fan effect by the Ribs 190, on the other hand, the outer region is more effective than the inner region, and if it depends only on this effect, the ribs 190 can be provided only in the radially outer region.

The first fluid channel 177, and preferably all first fluid channels formed in or on the bottom wall 184, are preferably at least in the region of a respectively assigned air passage opening 178, i. the first fluid channel 177 in the region of the air passage opening 178, bounded by a limiting member in the direction of the air outlet side 109. This limiting member is preferably formed by a particular annular and radially magnetized, permanent magnet rotor magnet 162 of the outer rotor 160 of the external rotor motor 150, which in an assembly of the fan 140, e.g. starting from a free end of the cup-shaped carrier 182, preferably pushed against the plurality of ribs 190 in the cup-shaped carrier 182 and fixed there.

On an inner side or the inner stator 130 side facing the

Cup-shaped support 182 is preferably a sleeve-shaped return part 168 of the outer rotor 160 rotatably disposed, to which, for example. the rotor magnet 162 of the outer rotor 160 is arranged and fixed to cooperate with the motor winding 132. The sleeve-shaped return part 162 is at least partially formed of a magnetically conductive material and preferably by

Injection molded on the molded plastic molded as a cup-shaped support 182 by the return member 162 is inserted, for example, as an insert in the injection mold and then the plastic in the

Injection mold is injected. In this case, the sleeve-shaped extends

The return part 168 preferably does not extend into the bottom wall 184 of the cup-shaped support 182 in order to avoid an arrangement of the sleeve-shaped return part 168 in the region of the at least one air passage opening 178.

During operation of the fan 100, the fan wheel 140 sucks in air when rotated in a direction of rotation indicated by an arrow 101 through the air inlet side 108, as indicated by an arrow 102. From this sucked air 102, the plurality of fan blades 180 generates the air flow 103 directed in the main conveying direction 105 through the fan housing 110, for example for cooling an external fan Device. This results from negative pressure of the cooling air flow 104 for cooling the bearing tube 172 and the bearing assembly 131 and the inner stator 130, which always in operation of the fan 100, starting from the Luftauslassseite 109 at least over the second fluid channel, eg the second fluid channel 175, the first fluid channel 177 and the at least one air passage opening 178 to

Vacuum side 185 'flows to be transported away from there with the air flow 103 in the main conveying direction 105. It should be noted, however, that the operation of a diagonal or axial fan as well as the functionality and the basic structure of the preferably electronically commutated

External rotor motor 150 are well known to those skilled in the art. Therefore, for the sake of simplicity and brevity of description, a further description thereof will be omitted here.

FIG. 2 shows the fan 100 of FIG. 1 with the fan wheel 140 forming the outer rotor 160, the inner stator 130 attached to the printed circuit board 176, which forms the outer rotor motor 150 with the outer rotor 160, and the fan housing 1 10. This is the majority connecting webs 1 17 connected to the flange 170, wherein the plurality of connecting webs 1 17 in addition to the connecting web 179 of Fig. 1 illustratively has three further connecting webs, which are identified by the reference numerals 274, 276 and 279.

The bearing tube 172 arranged on the flange part 170 is designed to form the second fluid channels 171, 175 as well as further second fluid channels, of which by way of example two second fluid channels with the reference numbers 271, 275

Marked are. The second fluid channel 271 is here similar to the second fluid channels 171, 175 provided for forming on the outer periphery of the bearing tube wall 122 of the bearing tube 172, i. in a region defined by the outer circumference of the bearing tube wall 122, two longitudinal webs 281, 282 formed on the bearing tube wall 122 and the central inner stator recess 139. Here, the longitudinal webs 281, 282 may be formed such that the inner stator 130 is supported in its axial direction thereto, e.g. at a paragraph provided for this purpose. However, the second fluid channel 275 is, for example, formed in or within the bearing tube wall 122 by way of example. It is, however, on it

It should be noted that only a single one of these fluid channel types is used can find and also a respective predetermined number of fluid channels application-specific can be specified.

In addition to the two fan blades 181, 185, the fan wheel 140 illustratively has three further fan blades 183, 187, 189. These have in analogy to the pressure sides 181 ", 185" and vacuum sides 181 ', 185' of the fan blades 181, 185 pressure sides 183 ", 187", 189 "and vacuum sides 183 ', 187', 189 ' each of the vacuum sides 181 ', 183', 185 ', 187', 189 'preferably each two Luftdurcht ttsöffnungen formed on the bottom wall 184 of the cup-shaped support 182 of the fan 140, wherein only the air passage openings on the vacuum sides 185', 187 'for simplicity and Accordingly, a further air passage opening 278 is provided in the region of the negative pressure side 185 'in addition to the air passage opening 178, and two air passage openings 287, 289 are provided in the region of the negative pressure side 187'.

Such as. can be seen in Fig. 1, Fig. 3, Fig. 5 to Fig. 9, are the

Air passage openings 178, 287, 289, 188, 120, 287, etc. are preferred

configured to allow fluid flow in the radial direction. This has the advantage that, on the one hand, the active fluid requirement can flow out of the interior 192 through the possibly present ribs 491, 492 without further deflection (for example in an axial direction), ie the flow resistance is kept relatively low. On the other hand, this allows in a simple manner a direct connection between the interior 192 and the negative pressure side 187 'of the

Fan blade 187.

In order to allow the fluid flow in the radial direction, the

Air passage opening 178, 287, 289, 188, 120, 287, etc., as shown in the figures extend in the radial direction, wherein the air passage opening 178 may be additionally opened in the axial direction, see. For example, Fig. 2. In these cases, the air passage opening 178 is at least partially formed to guide the fluid flow in the radial direction. The opening in the axial direction is particularly advantageous in the embodiment of the fan as an injection molded part, since it in the Making a demolding possible by moving the injection molds in the axial direction.

The air passage opening 178 may also extend slightly obliquely to the radial direction and be so large that a radial flow is possible. It is thus advantageous that the air passage opening 178 allows a fluid flow whose radial component is greater than the axial component thereof. This is made possible by the aforementioned embodiments, but also by

Embodiments of the air passage opening 178, which extend slightly obliquely to the radial direction.

It is advantageous if - as shown in the figures - the exit of the

Air passage opening 178 is open at least partially in a radial direction on the side facing away from the interior 192 side, so if you can see the opening from the corresponding radial side from the outside, as this is the

Flow through the radial direction easier. This passage in the radial direction is not prevented by the possibly additionally existing opening in the axial direction.

Fig. 3 shows the fan 140 of Fig. 1 and Fig. 2 to illustrate the cup-shaped carrier 182, on which the plurality of fan blades 180 is preferably integrally formed and in which the sleeve-shaped

Return member 168 and the rotor magnet 162 are arranged to form the outer rotor 160. In addition, Fig. 4 illustrates the preferred by

Injection molded mounting of the metal part 107, to which the rotor shaft 149 is secured against rotation, at the attachment portion 186 of

cup-shaped carrier 182.

FIG. 4 shows the fan wheel 140 of FIGS. 1 and 2 for clarification of FIG

Pressure sides 181 ", 183", 185 ", 187", 189 "of the fan blades 181, 183, 185, 187, 189 and the side 184 'of the bottom wall 184 of the cup-shaped carrier 182, on which the plurality of ribs 190 is formed preferably extend radially outward star-shaped or spoke-shaped, starting from a

Area in which the rotor shaft 149 secured against rotation on the metal part 107 is. In this case, in addition to the ribs 191, 193, three further ribs are illustratively designated by the reference numerals 491, 492, 493, which will be discussed below with reference to FIG.

FIG. 5 shows the fan wheel 140 of FIG. 4, in which approximately in the region of

Fan blade 187, the annular side wall 188 of the cup-shaped carrier 182, the sleeve-shaped return part 168 and the rotor magnet 162 are illustratively broken away to the Luftdurchts openings 287, 289 in the region of

Underpressure side 187 'of the fan blade 187 of Fig. 2 to illustrate. These are preferably formed in a predetermined circumferential angle range α of the fan blade 187 on the cup-shaped carrier 182. The circumferential angle region α preferably comprises at least one region of the negative pressure side 187 ', in which a negative pressure occurs in each case during operation of the fan 100 of FIGS. 1 and 2.

The Luftdurchtrittsoffnung 289 forms here with the ribs 491, 492 from a first fluid passage 578, and the Luftdurchtrittsoffnung 287 forms with the ribs 492, 493 a first fluid passage 577 from. These first fluid channels 577, 578 are analogous to the first fluid channel 177 of FIG. 1 formed on the bottom wall 184 of the cup-shaped support 182 and are at least partially covered by the rotor magnet 162, but are preferably partially open to the air outlet 109 side. Alternatively, the first fluid channels 177, 577, 578 may be e.g. be covered by a matching part of plastic or sheet metal.

FIG. 6 shows a section 600 of the fan wheel 140 of FIG. 3 to illustrate the attachment of the sleeve-shaped return part 168 to the annular side wall 188 of the cup-shaped support 182. In this case, the return part 168 is preferably injection molded between two annular shoulders 684 provided on the annular side wall 188 , 688 injected.

In addition, the rotor magnet 162 is fastened within the sleeve-shaped return-end part 168, preferably by pressing and / or gluing. This preferably has a minimum radial extent 602, which is greater than a maximum radial extent 601 of the metal part, which is likewise preferably injected by injection molding into the attachment portion 186 of the cup-shaped carrier 182 107 is to avoid an arrangement of the metal part 107 in the region of the rotor magnet 162.

There are fan wheels are known in which a metallic rotor pot is provided from magnetically conductive material. Such metallic rotor pots are

naturally very stable and also suitable for powerful fans. The solution shown is in direct comparison not as stable as a metallic rotor pot, since the metal part 107 and the return part 168 are interconnected only via the plastic. However, it has been found that for many applications the stability that can be achieved thereby is sufficient, and the production with the plastic connecting the parts 107, 168 is significantly easier, in particular in the area of the air passage openings 120 than with a metallic rotor pot, with corresponding openings in FIG need to be drilled the metallic rotor pot, which is time consuming and expensive.

Fig. 7 shows the fan wheel 140 of Fig. 3 in a slightly tilted position, thereby to the side 184 'of the bottom wall 184 of the cup-shaped carrier 182 formed plurality of ribs 190th

FIG. 8 shows a cutout 800 of the fan wheel 140 of FIG. 7 for clarification of the first fluid channel 177 formed in the region of the rib 191 and the air passage opening 178, as well as for clarification in the area of FIG

Air passage opening 178 against the annular shoulder 684 of the annular outer wall 188 of the cup-shaped support 182 adjacent, sleeve-shaped return part 168th

9 shows the fan wheel 140 of FIG. 1 and FIG. 2 for clarification of the plurality of air passage openings 120 formed on the cup-shaped support 182 in the region of the bottom wall 184. These are preferably in each case in the area between two adjacent in the circumferential direction of the fan 140. opposite ribs of the plurality of ribs 190 are arranged. For example, the air passage opening 289 is arranged in the region between the ribs 491, 492, etc. It should be understood, however, that the plurality of fins 120 are illustratively only recognizable on the bottom wall 184 here. However, the plurality of ribs 120 are shown in FIG. 1 - the air inlet side 108 of FIG

Fan housing 1 10 facing - side of the bottom wall 184 preferably not on this over or out of this.

FIG. 10 shows the fan wheel 140 of FIG. 1 and FIG. 2 to illustrate the illustration of a corresponding cooling of the bearing tube 172 as well as of FIG

Bearing assembly 131 and the inner stator 130 of Fig. 1 and Fig. 2 of the

Air passage openings 287, 289 in the direction of the negative pressure side 187 'of the

Fan blade 187 exiting cooling air flow 104 of FIG. 1. This is then generated as described above with that of the plurality of fan blades 180

Airflow 103 in the main conveying direction 105 of the fan 100 of Fig. 1 and Fig. 2 transported away.

11 shows the fan wheel 140 of FIG. 1 and FIG. 2 for clarification of the plurality of air passage openings 120 formed on the cup-shaped support 182 in the region of the bottom wall 184, as well as for illustrating the vacuum sides 181 ', 183', 185 ', 187'. , 189 'and the printed pages 181 ", 183", 185 ", 187", 189 "of the fan blades 181, 183, 185, 187, 189.

FIG. 12 shows a measurement diagram 1200 of operating parameters, in particular of critical temperature profiles, of the fan 100 of FIG. 1, which were detected at least partially using the thermoelements 198, 199 of FIG. 1 and in dependence on a respective volume flow in m ³ /. h, ie the air flow 103 of FIG. 1 conveyed by the fan 100, the respective volume flow being depicted on an abscissa 1202. Associated ordinates 1204, 1206 depict temperature differences in Kelvin and a respective room temperature in ° C, as well as a respective motor power in W of the external rotor motor 150 of FIG.

Reference numeral 1210 denotes the room temperature at which the measurement was carried out. This is about 24.5 ° C. The electrical power consumed by the fan 100 during the measurement is indicated by the reference numeral 1220 characterized. An increase in temperature as measured in the motor winding 132 of FIG. 1 is indicated by the reference numeral 1230. This is here in the range of 12 to 15 K. A corresponding increase in temperature in the ball bearing 173 of FIG. 1 is identified by the reference numeral 1240 and is at values between 7.5 and 1 1 K. A corresponding increase in temperature in the ball bearing 174 of FIG is designated by the reference numeral 1250 and is at values between 10 and 15 K.

13 shows a measurement diagram 1300 of operating parameters, in particular of critical temperature profiles, of a fan constructed according to the fan 100 of FIG. 1, in which a conventional fan impeller was used, so that with a corresponding cooling of the bearing tube 172 as well as the bearing assembly 131 and the inner stator 130 of FIG. 1, a reversal point known from the prior art occurs. The operating parameters or temperature profiles were in turn at least partially detected using the thermocouples 198, 199 of FIG. 1 and are illustrated as a function of a respective volume flow in m ³ / h, ie the air flow conveyed by the fan, wherein the respective

Volume flow is shown on an abscissa 1302. Associated ordinates 1304, 1306 depict temperature differences in Kelvin and a respective room temperature in ° C, as well as a respective motor power in W of the external rotor motor 150 of FIG.

Reference numeral 1310 denotes the room temperature at which the measurement was carried out. This is about 23.3 ° C. The electric power consumed by the fan during the measurement is indicated by the reference numeral 1320. On when measured in motor winding 132 of FIG. 1

recorded temperature increase is indicated by the reference numeral 1330. This is here in the range of 26 to 33 K. A corresponding increase in temperature in the ball bearing 173 of Fig. 1 is denoted by the reference numeral 1340 and is at values between 10 and 20 K. A corresponding increase in temperature in the ball bearing 174 of Fig. 1 is with the Numeral 1350 marked and is at values between 7.5 and 20 K. As can be seen from the measurement diagram 1300, a reversal point 1399 is present in which a corresponding cooling air flow for cooling the bearing tube 172 and the bearing assembly 131 and the inner stator 130 of FIG. 1 changes direction, ie in the region before the reversal point 1399 is the cooling air flow of the

Air intake side 108 of Fig. 1 directed to the air outlet side 109 and then rotates in the direction shown in Fig. 1. This results in a volume flow of about 500 or 550 m ³ / h temperature peaks in the motor winding 132 and the ball bearings 173, 174 of FIG. 1, as can be seen from the temperature increases 1330, 1340, 1350, since at the volume flow between about 410 and 550 m ³ / h no cooling of the bearing tube 172 and the bearing assembly 131 and the inner stator 130 of FIG. 1 takes place, which could lead to an abrupt failure of the fan.

In addition, it follows from a comparison with FIG. 12 that the

Temperature increases in the motor winding 132 and the ball bearings 173, 174 of FIG. 1 here make much less favorable and thus can lead to a reduction in a corresponding grease service life. As described above, this can lead to a shortening of the service life of the fan, which is operated without the fan wheel 140 according to the invention.

The figures and the description show a diagonal or axial fan 100 comprising: a fan housing 110 forming an air inlet side 108 and an air outlet side 109, a bearing tube 172 having a bearing tube wall 122 having a central bearing tube recess 124 for receiving a bearing assembly 131 trains; an external rotor motor 150 with an inner stator 130 and an outer rotor 160, which inner stator 130 has a central

Innenstatorausnehmung 139 and is at least partially disposed on the bearing tube 172; a fan wheel 140 which is mounted rotatably about the bearing arrangement 131 about a rotation axis 141 and is rotatably driven by the external rotor motor 150, which fan wheel 140 has a cup-shaped carrier 182 which defines an interior 192 on its cup-shaped inner side, and on which cup-shaped carrier 182 a A plurality of fan blades 181, 183, 185, 187, 189 for generating one in a main conveying direction 105 of the

Air inlet side 108 to the air outlet side 109 through the fan housing 1 10 directed air stream 103 is arranged; each fan blade 181, 183, 185, 187, 189 having a pressure side 181 ", 183", 185 ", 187", 189 "facing the air outlet side 109 and a vacuum side 181 ', 183', 185 ', 187' facing the air inlet side 108. And wherein the cup-shaped carrier 182 of the fan wheel 140 has a bottom wall 184 and an annular side wall 188, which bottom wall 184 forms on its air outlet side 109 side 184 'at least a first fluid channel 177, which at least one of the cup-shaped carrier 182 trained in the bottom wall 184

Air passage opening 178, which causes a fluid connection between the interior 192 and the negative pressure side 185 'of at least one fan blade 185, to at least partially caused by a negative pressure during operation

Generation of a cooling air flow 104 provided at least for cooling the external rotor motor 150 via the first fluid channel 177 and the at least one

Air passage opening 178 to the negative pressure side 185 'to allow.

According to one embodiment, the at least one first fluid channel 177 is delimited by a delimiting member 162 in the direction of the air outlet side 109, at least in the area of the at least one air passage opening 178.

According to one embodiment, the outer rotor 160 of the external rotor motor 150 is provided with a permanent magnet rotor magnet 162, wherein the

Rotor magnet 162 is annular and forms the limiting member 162.

According to one embodiment, the at least one air passage opening 287, 289 in a predetermined circumferential angle range α of the at least one

Fan blade 187 formed.

According to one embodiment, the predetermined circumferential angle range α comprises a region of the negative pressure side 187 'of the at least one fan blade 187, in which in each case a negative pressure occurs during operation.

According to one exemplary embodiment, a plurality of ribs 191, 193 are formed on the side 184 'of the bottom wall 184 of the cup-shaped carrier 182 facing the air outlet side 109. According to one exemplary embodiment, the bottom wall 184 provided with the plurality of ribs 191, 193, during operation, at least partially forms a radial fan wheel in order to at least support the generation of the cooling air flow 104.

According to one embodiment, the cup-shaped support 182 is formed as a molded piece made of plastic, in which a sleeve-shaped return part 168 is attached, in particular by injection molding.

According to one embodiment, the sleeve-shaped return part 168 does not extend into the bottom wall 184 of the cup-shaped carrier 182, around a

Arrangement of the sleeve-shaped Rückschlussteils 168 in the region of at least one Luftdurcht ttsöffnung 178 to avoid.

According to one exemplary embodiment, a metal part 107 is fastened in the bottom wall 184 of the cup-shaped support 182, in particular by injection molding, to which a shaft 149 rotatably mounted in the bearing tube 172 is fastened secured against rotation.

According to one embodiment, the metal part 107 has a maximum first radial extent 601 and a rotor magnet 162 of the outer rotor 160 of the outer rotor motor 150 arranged in the cup-shaped carrier 182 has a minimal second radial extent 602, the first radial extent 601 being smaller than the second radial Extension 602 to avoid an arrangement of the metal part 107 in the region of the rotor magnet 162.

According to one exemplary embodiment, at least one second fluid channel 171, 175 is formed in the region between the inner stator 130 and the central bearing tube recess 124, which at least one second fluid channel 171, 175 is in fluid communication with the air outlet side 109 on the one hand and with the inner space 192 on the other hand, around a cooling air flow 104 from the air outlet side 109 via the at least one second fluid channel 171, 175, then via the at least one first fluid channel 177 and the at least one air passage opening 178 to

Allow negative pressure side 185 '. According to one exemplary embodiment, the bearing tube 172 is connected to a flange part 170 of the fan housing 110, wherein the at least one second fluid channel 171, 175 passes through the flange part 170.

According to one embodiment, the at least one second fluid channel 171, 175 is formed in the bearing tube wall 122 of the bearing tube 172.

According to one embodiment, the at least one second extends

Fluid channel 171, 175 from the Luftauslassseite 109 of the fan housing 1 10 at least partially in the central Innenstatorausnehmung 139 in the direction of

Air inlet side 108 of the fan housing 1 10, preferably at least up to a region which is disposed on a side remote from the Luftauslassseite 109 of the fan housing 1 10 side of the inner stator 130.

Preferably, the air passage opening 178 is formed in the region of

Air passage opening 178 to allow fluid flow in the radial direction.

Preferably, the air passage opening 178 extends in a radial direction.

Preferably, those formed in the region of the bottom wall 184 extend

Air passage openings 120, 178 from the interior 192 to the negative pressure side

at least one fan blade 185.

Preferably, the first channel 177 is at least partially limited in the axial direction on the one hand by the bottom wall 184 and on the other hand by the inner stator 130. This allows the guidance of the fluid flow.

Preferably, the first channel 177 is limited at least in regions in the axial direction on the one hand by the bottom wall 184 and on the other hand by the rotor magnet 162. This allows the guidance of the fluid flow. Preferably, those formed in the region of the bottom wall 184 extend

Air passage openings 120, 178 from the interior 192 directly to the negative pressure side of at least one fan blade 185th

Preferably, the outlet of the air passage opening (178) on the side facing away from the interior (192) side is at least partially open in a radial direction.

Naturally, many modifications and modifications are possible within the scope of the present invention.

Thus, it is very complicated to form corresponding second fluid channels 171, 175 in the case of a bearing tube 172 made of metal. In such cases, the second fluid channels 171, 175 may also be omitted, which results in a poorer fluid flow, but which is partially compensated by the better thermal conductivity of the metal.

Claims

claims

1 . Diagonal or axial fan (100), which has

A fan housing (1 10) having an air inlet side (108) and a

Air outlet side (109) forms,

a bearing tube (172) having a bearing tube wall (122) forming a central bearing tube recess (124) for receiving a bearing assembly (131);

an external rotor motor (150) having an inner stator (130) and a

Outer rotor (160), which inner stator (130) has a central

Innenstatorausnehmung (139) and at least partially on the bearing tube (172) is arranged;

a fan wheel (140) which is rotatably supported about the bearing arrangement (131) about an axis of rotation (141) and is rotatably driven by the external rotor motor (150), which fan wheel (140) has a cup-shaped carrier (182) which is provided on its cup-shaped inner side defines an interior space (192), and on which cup-shaped carrier (182) a plurality of fan blades (181, 183, 185, 187, 189) for generating a in a main conveying direction (105) from the air inlet side (108) to the air outlet side ( 109) through the fan housing (1 10) directed air flow (103) is arranged;

each fan blade (181, 183, 185, 187, 189) having a pressure side (181 ", 183", 185 ", 187", 189 ") facing the air outlet side (109) and a negative pressure side (181 'facing the air inlet side (108). , 183 ', 185', 187 ', 189');

and wherein the cup-shaped carrier (182) of the fan wheel (140) has a

Bottom wall (184) and an annular side wall (188), which bottom wall (184) on its air outlet side (109) facing side (184 ') at least a first fluid channel (177) forms, which at least one cup-shaped support (182) in Has area of the bottom wall (184) formed Lufttsttsöffnung (178), which a

Fluid connection between the interior (192) and the negative pressure side (185 ') of at least one fan blade (185) causes, in operation, at least partially caused by negative pressure generating at least one for cooling the external rotor motor (150) provided cooling air flow (104) via the first fluid channel (177) and the at least one

Luftdurchtrittsöffnung (178) to the negative pressure side (185 ') to allow.

Fan according to claim 1, wherein the at least one first fluid channel (177) at least in the region of the at least one Luftdurchtrittsausoffnung (178) by a limiting member (162) in the direction of the air outlet side (109) is limited.

A fan according to claim 2, wherein the outer rotor (160) of the

External rotor motor (150) is provided with a permanent magnetic rotor magnet (162), wherein the rotor magnet (162) is annular and forms the limiting member (162).

Fan according to one of the preceding claims, wherein the at least one Luftdurchtrittsoffnung (287, 289) in a predetermined circumferential angular range (a) of the at least one fan blade (187) is formed.

A fan according to claim 4, wherein said predetermined circumferential angular range (a) comprises a portion of said negative pressure side (187 ') of said at least one

Fan blade (187) comprises, in which in each case a negative pressure occurs during operation.

Fan according to one of the preceding claims, wherein on the air outlet side (109) facing side (184 ') of the bottom wall (184) of the cup-shaped support (182) is formed a plurality of ribs (191, 193).

7. The fan of claim 6, wherein the bottom wall (184) provided with the plurality of ribs (191, 193) at least partially forms a radial fan during operation to at least support the generation of the cooling air flow (104).

8. Fan according to one of the preceding claims, wherein the

cup-shaped carrier (182) is designed as a molded piece made of plastic, in which a sleeve-shaped return part (168) is fixed, in particular by injection molding.

The fan of claim 8, wherein the sleeve-shaped return portion (168) does not extend into the bottom wall (184) of the cup-shaped carrier (182) to accommodate placement of the sleeve-shaped return portion (168) in the region of the at least one air passage opening (178) avoid.

10. Fan according to one of the preceding claims, wherein in the

Bottom wall (184) of the cup-shaped carrier (182) a metal part (107) is fixed, in particular by injection molding, to which one in the

Bearing tube (172) rotatably mounted shaft (149) is secured against rotation.

1 1. The fan of claim 10, wherein the metal member (107) has a maximum first radial extent (601) and a rotor magnet (162) of the outer rotor (160) of the outer rotor motor (150) disposed in the cup-shaped carrier (182) has a minimum second radial extent (602), wherein the first radial extension (601) is smaller than the second radial extension (602) to avoid an arrangement of the metal part (107) in the region of the rotor magnet (162).

12. Fan according to one of the preceding claims, wherein in the region between the inner stator (130) and the central Lagerrohrausnehmung (124) at least a second fluid channel (171, 175) is formed, which at least one second fluid channel (171, 175) on the one hand the air outlet side (109) and on the other hand with the interior (192) in

Fluid connection is,

a cooling air flow (104) from the air outlet side (109) via the at least one second fluid channel (171, 175), then via the at least one first fluid channel (177) and the at least one

Air passage opening (178) to the negative pressure side (185 ') to allow.

13. The fan of claim 12, wherein the bearing tube (172) with a

Flange part (170) of the fan housing (1 10) is connected, wherein the at least one second fluid channel (171, 175) through the flange part (170) performs.

14. The fan of claim 12 or 13, wherein the at least one second fluid channel (171, 175) in the bearing tube wall (122) of the bearing tube (172) is formed.

A fan according to any one of claims 12 to 14, wherein the at least one second fluid channel (171, 175) extends from the air outlet side (109) of the

Fan housing (1 10) at least partially in the central

Inner stator recess (139) in the direction of the air inlet side (108) of the fan housing (1 10) extends, preferably at least up to a region which on one of the Luftauslassseite (109) of the fan housing (1 10) facing away from the Innenstators (130) ,

16. Fan according to one of the preceding claims, wherein the

Air passage opening (178) is designed to be in the range of

Air passage opening (178) to allow fluid flow in the radial direction, wherein the air passage opening (178) preferably extends in a radial direction.

17. Fan according to one of the preceding claims, wherein the outlet of the Luftdurchtrittsoffnung (178) on the side facing away from the interior (192) side is at least partially open in a radial direction.