BE1030312B1 - Fluid machine - Google Patents

Abstract

The invention relates to a turbomachine (1) with at least one housing (10), with at least one electric motor (3) with a stator (30) which is fixedly arranged on the housing (10) and with a rotor (31) which can rotate relative to the stator (30). , with at least one shaft (4) which is fixedly connected to the rotor (31), the shaft (4) having at least one impeller (5) which is designed to generate a fluid flow (A) through its rotation, and with a bearing (2), which is arranged along the axis of rotation (X) of the shaft (4) between the electric motor (3) and the impeller (5). The turbomachine (1) is characterized in that the rotor (31) is arranged eccentrically to the stator (30) along the axis of rotation (X) by an axial offset (A).

Description

Description

Fluid machine

The invention relates to a turbomachine, a household or kitchen appliance with such a turbomachine and an electric motor for such a turbomachine.

In many technical areas it is necessary to generate a fluid flow. This can apply to liquids and in particular to water or aqueous liquids as well as to gases and in particular to air. For this purpose, turbomachines can be used, which usually suck in the fluid on a suction side and release it on a pressure side by means of an impeller rotating in a housing.

Depending on the design and application, turbomachines can be used, for example

Movement of air are also referred to as fans, blowers or fans.

Such fluid machines are also used in household and kitchen appliances

Generation of fluid flows used. For example, in a vacuum cleaner ı5, by means of such an air flow, dirt particles and the like from a surface, such as in particular a floor, are sucked into the vacuum cleaner and passed through at least one filter. Inside a tumble dryer or

In the washer-dryer, heated air is blown into the drum in order to dry the damp laundry there and remove the moisture from the drum with the air flow. With an oven, hot air can be blown into the cooking chamber in order to cook the food there. This can be done in a comparable way with a steamer with hot and moist air. Such turbomachines can also be used

Household and kitchen appliances for generating a liquid flow such as

Pumping out the washing liquor can be used in a washing machine. The impeller of such a turbomachine is driven for this purpose and the blades of the impeller ensure the desired movement of the impeller due to their design and arrangement

Fluids or for generating the fluid flow.

Electric motors are usually used to drive such turbomachines, which transmit their rotational movement to the impeller via a common shaft.

The impeller can also be referred to as the output of the turbomachine.

The electric motor is usually arranged in a fixed position in the housing of the turbomachine and the shaft is guided through the electric motor. It protrudes at one end

Shaft protrudes sufficiently far above the electric motor so that it is excellent

The impeller is placed at the end of the shaft. This end of the wave can also be called the dem

The shaft end facing away from the electric motor is called. The impeller is usually sufficiently enclosed by the housing of the turbomachine in order to suck in the fluid through at least one passage opening of the housing on the suction side and to pass it through at least one passage opening of the housing on the pressure side to the environment or to another component of a device such as a household appliance or one

To be able to hand over kitchen appliances.

The shaft is usually mounted so that it can rotate relative to the housing about a longitudinal axis of the turbomachine as an axis of rotation at two points by bearings such as roller bearings. The two bearings are usually on either side of the

Electric motor arranged to achieve a stable hold of the shaft relative to the housing. The rotor of the electric motor is arranged on the shaft between the two bearings and positioned within the stator of the electric motor. The excellent shaft end facing away from the electric motor, which carries the impeller, extends away from the rotor from one of the two bearings and is unsupported. ı5 Alternatively, it is known to mount the shaft of a turbomachine between the

To arrange the impeller and the rotor of the electric motor. In other words, it's not just that

Impeller but also the rotor is arranged at one end of the shaft, which is opposite the impeller, as described above. The bearing is arranged in between and is usually designed, for example, as a self-contained cartridge bearing, which can simplify assembly and reduce tolerances, see for example EP 2 401 516 B1 and EP 3 387 741 A1.

In any case, the stator or the stator of the electric motor is fixedly connected to the housing of the turbomachine and the rotor or the rotor is fixedly connected to the shaft, so that the rotor is rotated by the stator through electromagnetic interaction

Rotation axis can be driven to rotate the shaft. On the part of

For this purpose, the stator has electrical conductor coils, or coils for short, which are energized and can be referred to as excitation coils. The windings of the electrical conductor coils are wound around an iron core, which is usually laminated.

Accordingly, we can also speak of stator windings and stator laminations. Depending on the type of electric motor, the rotor can also have coils with an iron core, which can also be referred to as an armature, or permanent magnets. The magnets of the rotor, whether coils or permanent magnets, are arranged along the axis of rotation centrally to the iron core or to the stator laminations of the stator.

The invention therefore presents the problem of creating a turbomachine of the type described above with improved acoustic properties and/or with improved overall efficiency. In particular, this should be achieved over the entire service life if possible. At least there should be an alternative to well-known ones

Fluid machines are created.

According to the invention, this problem is solved by a turbomachine, by a household or kitchen appliance and by an electric motor with the features of the independent patent claims. Advantageous refinements and further developments of the invention result from the following subclaims.

The present invention therefore relates to a turbomachine with at least one

Housing, with at least one electric motor with a stator fixedly arranged on the housing and with a rotor which is rotatable relative to the stator, with at least one shaft which is fixedly connected to the rotor, the shaft having at least one impeller which is formed by its rotation a

To generate fluid flow, and with a storage which is along the axis of rotation of the

Shaft is arranged between the electric motor and the impeller.

The turbomachine according to the invention is characterized in that the rotor ı5 is arranged eccentrically to the stator along the axis of rotation by an axial offset.

In other words, the rotor is not arranged centrally or concentrically to the stator along the axis of rotation as previously known, i.e. the rotor and stator are arranged along the

The axis of rotation is not arranged symmetrically around a common center as previously known, but there is an axial offset along the axis of rotation to a predetermined, i.e. fixed, extent. The axial offset can also be as

external centering can be referred to.

The present invention is based on the knowledge that by means of the axial

Offset along the axis of rotation in one direction or the other, the acoustic

Behavior of the electric motor and thus also of the turbomachine as a whole can be positively influenced. Both the direction of the axial offset along the axis of rotation and the extent of the axial offset along the axis of rotation are as

Creative scope available. Additionally or alternatively, this can also

The efficiency of the electric motor and thus also of the turbomachine as a whole can be increased. In any case, this can be achieved in the long term because the axial offset along the axis of rotation is implemented constructively and thus extends over the entire

The lifespan of the electric motor or the turbomachine cannot change or can only change insignificantly. This also applies to a household or kitchen appliance with a turbomachine according to the invention.

According to one aspect of the invention, the rotor is arranged eccentrically to the stator along the axis of rotation by an axial offset towards the impeller. This can be one

Possibility of implementing the axial offset in the case according to the invention

Represent a fluid machine.

This can be advantageous in that the magnet of the rotor, i.e. its coils or permanent magnets, are arranged offset on the shaft along the axis of rotation in the direction of the impeller, an additional force in the same direction as the direction of action of connecting means such as screws can be effected, which can hold the electric motor on the housing. If, as previously known, the magnet of the rotor is arranged centrally or concentrically to the stator, due to tolerances, forces can arise in the effective direction of the connecting means or the

Screws come, or in the opposite direction. In the latter case, for example, so-called “fractional corrosion” could occur comparatively frequently, which is why the stator of the electric motor is usually glued to the housing in order to avoid “frictional corrosion”. This undefined state, i.e. axial migration of the

Magnets of the rotor along the axis of rotation in one direction or the other in permanent alternation could also lead to a loosening of the connecting elements or the

Lead screw connections.

However, according to the invention, an eccentric arrangement between the rotor and

Stator is made in such a way that the rotor is engaged relative to the stator, an additional force of the rotor on the stator can be generated along the axis of rotation towards the impeller or towards the housing, so that the stator can additionally hold or clamp on the housing. Movement of the rotor back and forth relative to the stator along the axis of rotation can also be avoided in this way, which could also lead to loosening of the connecting elements or screws.

According to a further aspect of the invention, the rotor is arranged eccentrically to the stator along the axis of rotation by an axial offset away from the impeller. This may be another way to implement the axial offset in the invention

Represent a fluid machine.

According to a further aspect of the invention, the stator has stator laminations and

Stator windings and the rotor has coils or permanent magnets, the

Coils or the permanent magnets of the rotor along the axis of rotation around the axial

Offset are arranged eccentrically to the stator laminations of the stator. In this case, the shaft can serve as an armature for the coils in sections. This can enable concrete implementation with such types of electric motors.

According to a further aspect of the invention, the coils or the permanent magnets of the rotor are arranged eccentrically to the stator laminations of the stator along the axis of rotation about the axial offset towards the impeller. This allows the corresponding properties and advantages described above to be implemented in such types of electric motors.

According to a further aspect of the invention, the coils or the permanent magnets 5 of the rotor are arranged along the axis of rotation about the axial offset away from the impeller eccentrically to the stator laminations of the stator. This allows the corresponding properties and advantages described above to be implemented in such types of electric motors.

According to a further aspect of the invention, the axial offset is between 0.5 mm and 1.5 mm. These can be suitable or advantageous dimensions, particularly for household and kitchen appliances, in order to implement the axial offset along the axis of rotation and thereby achieve the properties and advantages described above. In particular, in this way, the usual functioning of electric motors can be influenced as little or as little as possible. ı5 According to a further aspect of the invention, a balancing disk is arranged on the shaft along the axis of rotation between the rotor and the bearing. This can make it possible to position the shaft relative to the housing or one during assembly

Balancing the front part of the housing and thus unbalancing the shaft compared to the

To reduce or even avoid the rotation axis.

The present invention also relates to a household or kitchen appliance with a

Turbomachine as described above. In this way, the previously described features and advantages can be achieved in a household appliance or in a

kitchen appliance can be moved and used. This includes all household appliances as well

Kitchen appliances in which fluid flows have to be generated are considered.

The present invention further relates to an electric motor for use in a

Turbomachine as described above, this allows one according to the invention

Electric motor can be made available in order to be able to implement a turbomachine according to the invention as described above and to be able to use its properties and advantages.

An exemplary embodiment of the invention is shown purely schematically in the drawing

Will be described in more detail below. It shows

Figure 1 shows a longitudinal section through a turbomachine according to the invention.

The above figure is viewed in cylindrical coordinates. A longitudinal axis extends

X, which can also be referred to as the rotation axis X. A radial direction R extends away from the longitudinal axis X perpendicular to the longitudinal axis X. Perpendicular to the radial

A circumferential direction (not designated) extends in the direction R and around the longitudinal axis X.

Fig. 1 shows a longitudinal section through a turbomachine 1 according to the invention

In the present case, turbomachine 1 serves to generate a fluid flow (not shown) in the form of an air flow. Accordingly, the turbomachine 1 can also be used as

Fan 1, referred to as fan 1 or fan 1. However, the turbomachine 1 can also be used to generate a liquid flow.

The blower 1 has a housing 10, which is in a front housing part 11 and in a

Rear housing part 12, viewed along the axis of rotation X essentially

Flow direction of the air flow is divided. The front housing part 11 can also be used as

The upper part of the guide stage 11 and the rear part of the housing 12 are referred to as the end shield 12.

Facing the air flow, a housing cover 13 is arranged along the axis of rotation The side of the blower 1 which has the passage opening can therefore also be referred to as the suction side of the blower 1. The housing cover 13 can also be referred to as a suction hood 13.

The air flow is after the passage opening of the intake hood 13 between the

Suction hood 13 and the guide stage upper part 11 are passed through. Then he occurs

Air flow through through openings (not designated) of the guide stage upper part 11 which are provided with guide elements (not designated), which are also called guide stages of the guide stage

Upper part 11 can be referred to, through this and passes over others

Guide elements (not designated) of the end shield 12, which are also called guide stages

End shield 12 can be referred to, in the interior (not designated). From the interior of the end shield 12 or the housing 10, the air flow exits the housing 10 through further passage openings (not designated). This

Side of the housing 10 can be referred to as the pressure side.

In the area already described between the guide stage upper part 11 and the intake hood 13, an impeller 5 is arranged, which has a plurality of blades 50.

If the impeller 5 rotates about the rotation axis X of the blower 1, which corresponds to the longitudinal axis from its interior. This creates the air flow.

An electric motor 3 is arranged along the axis of rotation The electric motor 3 has a stator 30 or a stator 30, which has a plurality of stator laminations 30a, which are partially surrounded by stator windings s 30b. The stator laminations 30a together form an iron core 30a

Stator 30. The stator windings 30b can also be used as conductor coils 30b or as

Excitation coils 30b are referred to. The stator 30 of the electric motor 3 is through

Screwing fixedly arranged on the end shield 12. A rotor 31 or a rotor 31 of the electric motor 3 is arranged within the stator 30 and is fixed with a

Wave 4 connected. The rotor 31 of the electric motor 3 has a plurality of coils 31a, to which the corresponding portion of the shaft 4 serves as an armature, or a plurality of

Permanent magnets 31a. A radial air gap (not designated) is formed in the radial direction R between the stator 30 and the rotor 31 or between the radial inside of the stator laminations 30a and the radial outside of the coils 31a or the permanent magnets 31a.

The impeller 5 is fixedly arranged on an end (not designated) of the shaft 4 that faces the impeller 5 or that is remote from the electric motor 3. The shaft 4 extends through the housing 10 along the axis of rotation X. The rotor is also 31 of the

Electric motor 3 or its coils 31a or permanent magnets 31a are fixedly arranged on an end (not designated) of the shaft 4 facing the electric motor 3 or facing away from the impeller 5. At the same time, the shaft 4 is rotatably connected to the housing 10 via a bearing 2 in such a way that the radially outer bearing elements of the bearing 2 are held stationary by the bearing plate 12. For this purpose, the end shield 12 is designed, for example, as an injection molded part and sprayed onto the bearing 2 from the radial outside. Alternatively, the end shield 12 can also be connected to the bearing 2 by, for example, gluing. In this way, the shaft 4 can be rotated relative to the housing 10 by means of the electric motor 3. This rotation can be applied to the

Impeller 5 is transferred.

The area of the end shield 12, which encloses the bearing 2, protrudes radially outwards into the interior of the end shield 12 or the housing 11

A plurality of cooling fins (not designated) which extend both radially and elongated in the direction of the rotation axis X and are arranged spaced apart from one another in the circumferential direction U. The cooling fins are formed in one piece with the end shield 12 and serve to remove heat from the bearing 2, which is generated there by friction

Operation can be released into the air flow.

The bearing 2, which can also be referred to as the rotor bearing 2, consists in the exemplary embodiment under consideration on two bearings 21, 22 in the form of two deep groove ball bearings 21, 22, which are spaced apart from one another along the axis of rotation X and are fixed radially on the inside by means of the corresponding bearing elements (not designated). , for example by pressing, gluing or shrinking, on the shaft 4 and radially on the outside by means of the corresponding bearing elements (not designated) by, for example, gluing or

Injection molding are connected to the end shield 12. Radially between the respective

Bearing elements of the two deep groove ball bearings 21, 22 are each a plurality of

Rolling elements in the form of balls (not designated) are arranged, which enable the 100 rotational mobility of the shaft 4 relative to the housing 10. Alternatively, the

Storage 2 can also be implemented using a cartridge chamber 2.

There is one between the rotor 31 and the bearing 2 along the rotation axis X

Balancing sheath 40 arranged on the shaft 4, which is used for balancing.

According to the invention, the coils 31a or the permanent magnets 31a of the rotor 31 ı5 are arranged eccentrically to the stator laminations 30a of the stator 30 along the axis of rotation In other words, the coils 31a or the permanent magnets 31a of the rotor 31 are arranged along the rotation axis are engaged relative to the 20 stator laminations 30a of the stator 30. This avoids a centric or concentric arrangement of the coils 31a or the permanent magnets 31a of the rotor 31 along the axis of rotation X relative to the stator laminations 30a of the stator 30.

This can affect the acoustic behavior and the overall efficiency of the invention

Improve turbomachine 1 and increase its service life. 25 Due to the axial offset A of the coils 31a or the permanent magnets 31a of the rotor 31 along the axis of rotation and thus supports the holding forces of the screws 32.

This also prevents movements back and forth between the rotor 31 and stator 30 due to manufacturing and assembly tolerances along the axis of rotation X, which could have a weakening effect on the connections of the screws 32.

List of reference symbols (part of the description)

A axial offset

R radial direction

X longitudinal axis; Axis of rotation 1 turbomachine; Fan; Fan; Fan

Housing 11 Front part of the housing; Guide stage upper part 0 12 Rear part of the housing; End shield 13 housing cover; Intake hood 2 storage; rotor bearing; cartridge bearing 21 first bearing 22 second bearing 3 electric motor 30 stator or stand of the electric motor 3 30a stator laminations; Iron core 30b stator windings; conductor coils; excitation coils 31 rotor of the electric motor 3 31a coils; permanent magnets 32 connecting elements; Screws 4 shaft 40 balancing disk 5 impeller 50 blades

Claims (10)

Patent claims 1. Turbomachine (1) with at least one housing (10), with at least one electric motor (3) with a stator (30) fixedly arranged on the housing (10) and with a rotor (31) which is rotatable relative to the stator (30), with at least one shaft (4) which is fixedly connected to the rotor (31), the shaft (4) having at least one impeller (5) which is designed to generate a fluid flow (A) through its rotation, and with a Bearing (2), which is arranged along the axis of rotation (X) of the shaft (4) between the electric motor (3) and the impeller (5), characterized in that the rotor (31) rotates along the axis of rotation (X) about an axial Offset (A) is arranged eccentrically to the stator (30). 2. Flow machine (1) according to claim 1, wherein the rotor (31) is arranged eccentrically to the stator (30) along the axis of rotation (X) by an axial offset (A) to the impeller (5). 3. Turbomachine (1) according to claim 1, wherein the rotor (31) is arranged eccentrically to the stator (30) along the axis of rotation (X) by an axial offset (A) away from the impeller (5). 4. Turbomachine (1) according to one of claims 1 to 3, wherein the stator (30) has stator laminations (30a) and stator windings (30b) and wherein the rotor (31) has coils (31a) or permanent magnets (31a), the Coils (31a) or the permanent magnets (31a) of the rotor (31) are arranged along the axis of rotation (X) by the axial offset (A) eccentrically to the stator laminations (30a) of the stator (30). 5. Turbomachine (1) according to claim 4, wherein the coils (31a) or the permanent magnets (31a) of the rotor (31) along the axis of rotation (X) by the axial offset (A) to the impeller (5) are eccentric to the stator laminations (30a) of the stator (30) are arranged. 6. Turbomachine (1) according to claim 4, the coils (31a) or the permanent magnets (31a) of the rotor (31) along the axis of rotation (X) by the axial offset (A) away from the impeller (5) eccentrically to the stator laminations ( 30a) of the stator (30) are arranged. 7. Turbomachine (1) according to one of the preceding claims, wherein the axial offset (A) is between 0.5 mm and 1.5 mm. 8. Turbomachine (1) according to one of the preceding claims, characterized in that a balancing disk (40) is arranged on the shaft (4) along the axis of rotation (X) between the rotor (31) and the bearing (2). 9. Household or kitchen appliance with a turbomachine (1) according to one of the preceding claims. 10. Electric motor (3) for use in a turbomachine (1) according to one of claims 1 to 8,