DE102016214696A1 - Electric disc motor with media separation in the motor gap - Google Patents

Abstract

An electric disk motor comprises: a rotor (10) having a member to be moved (105); and a stator (10), wherein the stator is arranged with respect to the rotor (20) such that there is a motor gap (30) between the rotor and the stator, the rotor (10) having a recess (40) in which the stator (20) is disposed, the rotor (10) being disposed in a first region (50) at a first pressure, the stator (20) being disposed in a second region (60) at a second pressure the second pressure is different from the first pressure, and wherein in the motor gap (30) an encapsulation material (70) is arranged, by which the first region (50) is separated from the second region (60).

Description

The present invention relates to electric motors, and more particularly to electric disc motors.

The EP 2 549 113 A2 discloses a magnetic rotor and a rotary pump with a magnetic rotor. The rotor is for driving a fluid in a pump housing within a stator of the rotary pump magnetically non-contact drivable and storable. In addition, the rotor is encapsulated by means of an outer encapsulation comprising a fluorinated hydrocarbon. Within the encapsulation, the rotor comprises a permanent magnet encased in a metal jacket. The rotary pump includes a pump housing having an inlet for supplying a fluid and an outlet for discharging the fluid. The fluid is, for example, a chemically aggressive acid with a proportion of a gas, e.g. As sulfuric acid with ozone. To convey the fluid, a magnetic rotor is magnetically non-contact in the pump housing. The rotor is further provided with a magnetic drive having electric coils. The stator is formed with laminated iron, which is in magnetic operative connection with the permanent magnet of the rotor. The drive is designed as a bearingless motor in which the stator is designed as a bearing stator and drive stator at the same time. The rotor is designed as a pancake, wherein the axial height of the rotor is less than or equal to half the diameter of the rotor.

The Dissertation ETH No. 12870, "The bearingless disk motor", N. Barletta, 1998 , discloses magnetically supported disc motors. Magnetic bearings work completely free from contact, wear, maintenance and lubricant. For the active stabilization of a degree of freedom, two controllable electromagnets including electronic control are required. The bearingless disc motor is used within a bearingless blood pump as a bearingless disc motor with active axial bearing, as a miniature disc motor, or as a bearingless bioreactor. By a combination of passive reluctance magnetic bearings and bearingless motor, it is possible to completely support a disc rotor with only two actively stabilized radial degrees of freedom. Requirements for a large air gap, which is necessary in hermetic systems, are met by the choice of a bearingless permanent magnetically excited synchronous motor. A bearingless disc motor suitable for driving an axial pump for cardiac assist is designed for speeds of 30,000 revolutions per minute, resulting in a smaller size.

Commercial electric disc motors are also known as "Pan Cake Motor". The engine concept illustrated in the two preceding references is characterized in that the stator extends around the rotor. Such engines are also referred to as internal rotor.

In the case of the internal rotor concept, there is the problem that the stator always has to be larger than the rotor, that is, the size and design of the rotor is always limited by the stator housing or that the rotor dominates the formation of the stator. Thus, the field of application of such a disc motor, which is designed as an internal rotor, limited.

In addition, disk motors generally have the problem that the rotor, regardless of whether it is designed as an internal rotor or external rotor, pressure differences or pressures in certain directions is exposed. These pressures cause a bearing to be loaded in the direction of pressure acting on the rotor, thus increasing wear, or, if rotor deflection is allowed, the rotor is deflected in that direction and thus leeway for this deflection must be provided. In particular, when the pump is used to pump a medium from a pressure area at a first pressure to a pressure area at a second pressure, or to generate such a pressure difference at all, complex design measures must be taken to either a required To achieve wear resistance, or to provide a margin for an occurring deflection.

All this means that the design effort of the disc motor increases, and thus the susceptibility to errors increases, while the application is limited.

The object of the present invention is to provide a flexible disc engine concept.

This object is achieved by an electric disk motor according to claim 1, a heat pump according to claim 23 or a method for producing an electric disk motor according to claim 25.

According to one aspect, the electric disc motor is designed as an external rotor. This means that the rotor has a recess in which the stator is arranged. This rotates the rotor around the stator. This makes it possible that a construction of the rotor can be defined directly by the application of the rotor and not by the fact that always, as with an internal rotor, it must be ensured that still a stator housing with corresponding magnetic coils around the rotor has space. On the other hand, a media or pressure separation of the disc motor is made so that in the motor gap, which is arranged between the rotor and the stator, an encapsulation material is provided around the stator, so that the entire stator media and pressure moderately separated from the area is, in which the rotor is located. In this way, all coil connections for the motor coils in the stator can be led out of the motor without problems, because the entire region of the stator lies in the ambient pressure or ambient medium and not in the delivery region in which the rotor is arranged. This also avoids overvoltage problems and similar effects that occur when high voltages are used in low pressure areas because the adjacent stator coils are all separated from the low pressure area by the encapsulation material located in the motor gap. This is particularly important when the rotor is operating in a low pressure area, such as a pressure range below 100 mbar, which occurs when the rotor is used as a compressor element in a heat pump that uses water as the working fluid. But even if the rotor operates at a higher pressure than the stator, the media or pressure separation by an encapsulation material in the motor gap is particularly advantageous.

By using an external rotor in conjunction with a media / pressure separation by an encapsulation material in the motor gap, an electric disk motor is thus provided which can be constructively produced with little complexity, which has no problems with respect to overvoltage effects which would occur when relatively high voltage coils be applied in areas of low pressure, and is particularly suitable for high speeds. The latter advantage results from the fact that permanent magnets, which are mounted on the rotor and define the magnetic gap on the rotor side, are supported by the rotor material itself "outwards". This is particularly important at high speeds, such as over 50,000 revolutions per minute, because the centrifugal forces occurring there can be problematic, especially in internal rotors, to the extent that the permanent magnets must be secured there with great effort.

On the other hand, because the rotor is arranged around the stator, the larger rotor diameter is again particularly advantageous, especially at speeds above 50,000 revolutions per minute, because, as in a gyroscope, the rotation of the rotor itself or its axis of rotation is additionally stabilized. This effect occurs in electric disc motors with relatively small rotor diameters, as z. B. used in internal rotors, less or not on.

In another aspect, the electric disc motor is used as an external rotor or as an internal rotor. It has a rotor having a member to be moved and a stator which is arranged with respect to the rotor so that a motor gap between the rotor and the stator is formed. The electric disc motor is configured to convey a medium from a source region to a target area through the moving element, wherein a target pressure in the target area is higher than a source pressure in the source area. The pressure acting on the rotor due to the pressure difference is reduced according to this aspect by a pressure reducer, to the effect that a pressure in the engine gap, ie where the magnetic interaction between rotor and stator takes place, less than the target pressure and greater than or equal to the source pressure is. This ensures that the rotor is no longer or at least less burdened in a particular direction due to the pressure difference between the source pressure and target pressure, which would lead to a resulting pressure and thus to a deflection or an increase in wear of the bearing.

This means that the rotor can indeed promote the required pressure difference between input and output, ie between source area and target area, but that no such or a reduced pressure difference is present in the motor gap and thus in the area of interaction between rotor and stator. This is the example of a bearingless motor, which is axially only passively supported, such as reduced by a magnetic bearing, an axial deflection due to the operation of the electric disc motor or even avoided.

However, the example of a contact-mounted rotor, so a rotor which is mounted with a ball bearing, is avoided by the pressure reduction, that the pressure is transferred to the bearing and the bearing wear increases. The pressure reduction in the motor gap thus leads to a motor wear or bearing wear is reduced or that in the case of wear-free bearings, so non-contact bearings necessary scope for a deflection of the rotor due to the resulting pressure on the rotor in a certain direction in the axial or Even in the radial direction can be reduced because due to the operation of the rotor no such deflections or only very small deflections compared to the situation in which no special mechanical pressure reduction is made takes place.

The pressure reduction in the engine gap is equally useful for external rotor and inner rotor. Even with an internal rotor, it is advantageous that The rotor during operation undergoes no much higher deflection situation than in the state. Thus, even with an internal rotor clearances can be reduced, so margins between the rotor and a guide element, which limits the fluid flow area in which the rotor acts to the outside.

In preferred embodiments, the pressure reduction is performed by two flow resistors, by a first flow resistor disposed between the target area and the engine gap, and a second flow resistance disposed between the engine gap and the source area. In particular, the flow resistance between the motor gap and the target area is made larger than the flow resistance between the motor gap and the source area, so that the flow resistance between the motor gap and the target area reduces a short circuit for the pressure, while the flow resistance between the motor gap and the source area reaches, that in the engine gap, the low pressure acts, which also acts in the source area. In particular, when the motor is designed as an external rotor, going to the fact that the stator is arranged in a recess of the rotor, it is preferred to attach the flow resistance between the target area and the motor gap as far as possible outside the rotor, so that as large as possible the rotor surface facing the stator is disposed in an area which is at the low swelling pressure and the pressure which is smaller than the target pressure. In contrast, it is preferable to attach the second flow resistance between the engine gap and the source region as centrally as possible, ie relatively centrally in the rotor in order to achieve the same conditions as possible along the circumference in the engine gap.

In preferred embodiments, the pressure reducer includes a labyrinth seal between the target area and the engine gap that provides a defined and relatively large flow resistance and, alternatively or additionally, a bore in the rotor between the engine gap and the source region that provides a relatively small flow resistance. Even the use of either only one labyrinth seal or only one hole, ie the use of only one flow resistance between source area and motor gap or target area and motor gap already leads to a pressure reduction in the motor gap and thus to a reduced deflection of the rotor with respect to the stator during operation in the case of a non-contact Magnetic bearing and in particular in the case of an axially passive bearing, or to a reduction in wear in the case of a contact bearing, such as a ball bearing due to the reduced load during operation.

The first aspect of the encapsulation material in the motor gap and the second aspect of the pressure reducer may be preferably combined, such that an external rotor disc motor has both the encapsulation in the motor gap and the pressure reducer. However, the two aspects can just as well be used alternatively to one another and, with regard to the pressure reducer, not only for the external rotor, but also for an internal rotor. In addition, both aspects can be used separately or together for contact bearings, but the use of magnetically levitated rotors is preferred and in particular of axially passive bearings, i. H. axially unregulated bearings and radially active controlled magnetic bearings.

Preferred embodiments of the present invention will be explained below in detail with reference to the accompanying drawings. Show it:

1A an external rotor according to a first aspect;

1B an electric disk motor according to a second aspect, which is formed as an external rotor or inner rotor;

1C an inner rotor according to the second aspect;

1D a preferred implementation of the second aspect with two series-connected flow resistors;

2A a cross section through an electric disk motor according to the first aspect;

2 B a cross section through an electric disc motor according to the second aspect, in which the first aspect is also realized;

3 a cross-section through a detailed representation of an implementation of the flow resistance by means of a labyrinth seal;

4 a schematic representation of a rotor and the forces acting on it with respect to the second aspect;

5 a schematic representation of a magnetic bearing on the example of an internal rotor;

6 a cross-sectional view of an external rotor with increased return element; and

7 a schematic cross section through a heat pump with the electric disc motor according to the first or second aspect.

1A shows a cross section through a schematically illustrated electric disc motor with a rotor 10 having an element to be moved. In addition, a stator 20 present, the stator 20 so with respect to the rotor 10 arranged is that a motor gap 30 exists between the rotor and the stator. The rotor 10 further comprises a recess 40 in which the stator 20 is arranged.

In addition, the rotor 10 in a first area 50 arranged with a first pressure p ₁ . Furthermore, the stator is in a second area 60 having a second pressure p ₃ , which differs from the first pressure p ₁ . At the in 1A In the embodiment shown, the first pressure is exemplified by the pressure inside the electric disc motor of FIG 1A , On the other hand, the second pressure is, for example, the atmospheric pressure or the atmospheric pressure when the disc motor is disposed in the atmosphere, or a pressure different from the atmospheric pressure when the disc motor is disposed in a region different from the atmospheric pressure. Further, in the engine gap 30 an encapsulation material 70 arranged through which the first area 50 from the second area 60 is disconnected. The separation takes place by way of example in that the encapsulation material in the in 1A shown embodiment completely encloses the stator, and that connecting cables 80 for the coils attached to the stator and those in 1A are not shown to supply the coils with electrical power through the encapsulant through to the outside, ie in the second area 60 be guided. The electric disc motor is designed as a conveyor motor and comprises an inlet 90 for a working medium and an outlet 100 for the working medium conveyed by the disc motor. As it is in 1A is shown, the pressure inside the disc motor p _{1 is} different from the pressure p ₃ outside the disc motor. Only preferably, the pressure p ₁ in the interior of the disc motor is lower than the pressure outside the disc motor. Similarly, the pressure outside the disc motor may be lower than the pressure inside, ie inside the motor housing.

In particular, in 1A further illustrated that the rotor and the stator in a motor housing 110 are arranged, wherein the motor housing has an opening through which the encapsulating material 70 extends. The encapsulation material or an element to which the encapsulation material is connected is on the motor housing 110 by a sealing ring shown schematically 120 attached, allowing a pressure-tight connection between the encapsulating material 70 and the motor housing 110 over the sealing ring 120 , which may be an O-ring, for example, is present. This is in 1A an external rotor realized as an exemplary electric disc motor in which the rotor is moved within a motor housing, while the coils of the stator and in particular the region of the stator, which is arranged at the motor gap, not communicating with the internal pressure p _{1 of} the disc motor, but with the External pressure communicates what is particularly advantageous in terms of electrical supply of the typically mounted in the stator coils. In particular, when the internal pressure p _{1 is} smaller than the external pressure p ₃ , there are significant advantages in terms of coil over-shots and other effects that the coils are not in the low pressure region but are encapsulated in the low pressure region.

In addition, the encapsulation of the coils relative to the interior of the disc motor has advantages that the coils do not come into contact with the medium to be conveyed and are therefore not exposed to corrosion due to the medium to be pumped, the medium may be, for example, water or water vapor. 1A further shows that the rotor 10 with permanent magnets 130 which faces the stator-side region, which typically has stator-side poles on which magnetic coils are wound, about the motor gap 30 define.

1B shows an electric disc motor according to a second aspect, which also has a rotor 10 which has a stator 20 Opposite to the engine gap 30 define. In particular, in the second aspect, which is in 1B is shown, the electric disc motor is designed to move through the moving element, which is connected to the rotor 10 is connected, and that with 1B together with the rotor 10 shown is a medium from an inlet 90 or a source area 90 , in which a smaller pressure prevails, in a target area 100 or to an outlet 100 the target area has a high pressure, or more generally, a greater pressure than the source area. In addition, the electric switching motor is designed to be a pressure reducer 140 designed to reduce a pressure acting on the rotor due to the different pressures in the source area and in the target area. In particular, the pressure reducer is designed so that a pressure in the motor gap 30 is smaller than the target pressure or the large pressure, but is greater than or equal to the swelling pressure. The pressure reducer 140 is thus designed to reduce the pressure in the motor gap compared to a situation where the pressure reducer is not present 30 towards the greater pressure in the target area and optimally equal to the pressure in the source area make or bring between the target pressure and the source pressure.

1D shows an alternative implementation of the electric disc motor of 1B in turn, a stator 20 is present, which is now part of the motor housing 110 forms. The stator is also provided with coils 150 provided, the permanent magnets 130 of the rotor 10 lie opposite to the engine gap again 30 to build. Further, the rotor 10 with an element formed here above the rotor and connected to the rotor to be moved 105 connected. The pressure reducer 140 in turn is intended to be in the engine gap 30 to reduce the pressure, namely the pressure in the target area, ie the pressure at the outlet 100 ,

As it is in 1D is shown, the pressure reducer comprises 140 for example, a first flow resistance 140a between the target area 100 and the engine gap 30 and a second flow resistor 140b between the engine gap 30 and the source area 90 or the inlet 90 , The two flow resistances 140a . 140b are preferably both present. Depending on the implementation, however, it may already be sufficient to achieve a reduction of the pressure acting on the rotor due to the operation of the disc rotor, only the first flow resistance between the target area and the motor gap or, alternatively to the first flow resistance, the second flow resistance 140b between the engine gap and the source area. Preferably, the first flow resistance 140a if both flow resistances 140a . 140b are provided, a higher value than the second flow resistance 140b , This means that the pressure in the motor gap 30 preferably more of the high pressure in the target area 100 differs as the pressure in the engine gap 30 differs from the pressure in the head region when the electric disk motor is operated.

2A shows a preferred embodiment of the electric disc motor according to the first aspect of the example of an embodiment for a Radialradkompressor that can be used at high speeds over 50,000 revolutions per minute and up to, for example, 90,000 revolutions per minute within a heat pump operated with, for example, water as the working medium can be.

2A shows an implementation of the disc motor according to the first aspect, in which the stator 20 with the encapsulating material 70 is encapsulated, so that the media separation between the area of high and low pressure across the engine gap 40 takes place. The stator 20 is provided with coils in 2A not shown, however, via the access lines 80 passing through the encapsulating material 70 extend or, if the encapsulation encapsulate only the motor gap and parts of the stator, already in the surrounding area 60 are located.

The rotor, passing through the permanent magnets 130 , a return element comprising the permanent magnets 160 as well as additional safety bandage 170 is formed, is also with the element to be moved 105 connected in 2A is shown as a radial wheel with blades only schematically. In particular, the electric disk motor is formed around the radial wheel 105 and the rotor 10 within a guide element 180 to turn that over a travel 190 from the respective blade ends of the radial wheel 105 is spaced. The radial wheel is configured to typically deliver vapor from an evaporator in which a lower pressure p ₀ prevails to a first pressure p ₁ . This first pressure p ₁ typically prevails at an exit of the radial impeller, also referred to as an impeller, as shown in FIG 2A is shown schematically. Typically, the guide member is coupled to a Leitraum, so that the accelerated by the rotation of the radial wheel steam is brought into the Leitraum, where it is brought due to the continuing further demand of steam through the radial to a higher target pressure p ₂ , in the liquefaction of the Heat pump prevails, as is in 2A is shown. In the external rotor is the height of the electrically effective stator 20 smaller than a diameter of the stator, and preferably smaller than half the diameter of the stator. If, however, the inner rotor is considered, so is in this, if 1C is taken as reference, the height of the electrically active rotor is preferably smaller than the diameter of the electrically active rotor, and preferably even smaller than half the diameter of the rotor.

2 B shows an embodiment of the electric disc motor according to the second aspect, in connection with an application for a radial wheel of a compressor of a heat pump, as shown in FIG 2A has been shown. In addition to the in 2A Elements shown are in the in 2 B shown embodiment, the two flow resistors 140a . 140b , based on 1D have been described trained. In particular, the pressure reducer comprises 140 at the in 2 B shown embodiment as an exemplary second flow resistance 140b a hole 200 in the rotor 105 which is adapted to a media passage from the motor gap 40 to the source area or inlet 90 to allow in the compressor. This makes it possible for a media passage through the element to be moved 105 , which is connected to the rotor is reached.

In addition, at the in 2 B shown embodiment of the pressure reducer 140 formed to a plurality of structural elements 210a . 210b . 210c to have, between the target area and the outlet from the Radialrad, which also with 100 in 2 B is shown, and the engine gap 140 available. This is due to the interaction of the plurality of construction elements 210a - 210c a pressure drop from the target area 100 , which has a pressure p ₁ , reaches the engine gap, which only has a pressure p ₁ ', which is smaller than the pressure p ₁ and greater than or equal to the pressure p ₀ in the source region, ie at the inlet 90 is. In particular, a first construction element of the plurality of construction elements is attached to the rotor. This construction element is in the in 2 B embodiment shown, the construction element 210b , Moreover, one of the design elements of the plurality of structural elements is a motor housing, such as the motor housing 110 attached, this construction element as a construction element 210a respectively. 210c is designated. Furthermore, the two construction elements, which are referred to as projecting rings, which in cross section in 2 B are shown are arranged so as to cause a pressure drop in their interaction. In particular, the construction elements form 210a - 210c a labyrinth seal. At the in 2 B Shown embodiment, the construction elements are each formed as projecting rings. However, they can also be designed as alternative construction elements, which from a surface of the motor housing 110 on the one hand and the rotor or the moving element on the other hand protrude to cooperate, such that the rotor with respect to the motor housing can be rotated, and such that due to the close placement of the structural elements to each other, a pressure drop occurs, so that the pressure p ₁ ' within the labyrinth seal with the construction elements 210a - 210c is less than the pressure p ₁ outside the labyrinth seal.

3 shows an alternative representation on an enlarged scale with respect to the embodiment of 2 B , So are further construction elements 212a - 212d formed, again the construction elements 212a . 212c on the housing 210 are arranged, and the construction elements 212b . 212d on the housing 210 or the moving element 105 are arranged. In contrast to the construction elements 210a to 210c respectively. 210d from 3 that extend radially with respect to rotation of the rotor are the structural elements 212a - 212d axially with respect to a rotation of the rotor 10 arranged. In one implementation, both radial and axial or alternatively oriented structural members may be provided as a labyrinth seal, or only radial structural members 210a - 210d or only axial construction elements 212a - 212d or only in other directions trained design elements.

In addition, it is not absolutely necessary that only a relatively small number of construction elements, such as in 2 B shown in interaction, but it can also be more or even less design elements, ie z. B. only two construction elements or four or more construction elements interact. In addition, it is also possible that more design elements are mounted on the rotor than on the housing or vice versa.

In one implementation, the structural elements could also be mounted between the rotor and stator outside the motor gap. However, it is used in the application 2 B or altogether preferably, to attach the construction elements between the rotor / element to be moved and the motor housing, since then the construction elements or the associated flow resistance R ₁ 140a between the target area 100 and the engine gap 30 as far outside with respect to the rotor is attached, while at the same time the second flow resistance, ie the bore 200 Through the rotor as possible inside and preferably even axially mounted directly in the rotor. This ensures that the largest possible area of the rotor, and above at the in 2 B shown orientation, which is also a preferred orientation for this disc motor in an application of a heat pump compressor is not exposed to the target pressure p ₁ , but only the reduced pressure p ₁ ', so that by the operation of the rotor, by the ultimately different pressures p ₁ and p ₀ occur, yet no deflection of the rotor will take place down or only a very small deflection. This allows the scope 190 between the guide element 180 and the radial wheel 105 be made very small, so that a compressor with a good efficiency is obtained.

On the other hand, allows the low deflection of the radial wheel in the axial direction, ie in the 2 B shown below, that the rotor can be magnetically stored and in particular with a magnetic bearing, which is passive in the axial direction, that is not regulated in this direction, but is regulated only in the radial direction. Thus, only one regulation with respect to a single, so the radial direction is necessary. This leads to an electric disc motor, which despite the considerable speeds it is able to afford a has simple storage control concept, since an axial bearing control is not necessary, the rotor still with a small margin to the guide element 180 can be operated to achieve high efficiency.

4 shows a schematic representation of the forces acting on the rotor. The rotor 10 or the element to be moved 105 is again shown schematically as a radial wheel in cross-section, but the individual blades are not specifically shown for clarity, but are immediately clear to those skilled. When the rotor is operated, there is a low evaporation pressure p ₀ in the source area, while in the target area there is a higher pressure p ₁ at the outlet of the radial wheel which is brought to the even higher condenser pressure by the guide space adjacent the radial wheel. The output pressure p ₁ presses on the upper relatively large surface of the radial wheel with a force F ₁ , which is equal to the product of p ₁ and the surface A ₁ , ie the surface in the plan view of the rotor 10 from above.

In addition, a small pressure F ₀ acts from below on the rotor, which is equal to the product of the low swelling pressure p ₀ and the relatively small area A ₀ .

In addition, a weight F _g acts on the rotor, which is equal to the mass of the rotor m _R times the gravitational acceleration g. In addition, a force F _M acts in turn upward, which is equal to a change in mass with time multiplied by the speed of the mass flow, which the radial wheel sucks from bottom to top. The weight and the force due to the mass flow are given from the outside. The same applies to the dimensions of the areas A ₀ and A ₁ . However, by the pressure reducer 140 lowered according to the present invention, the pressure p ₁ . Thus, the difference between p ₀ · A ₀ - p ₁ · A ₁ is made as small as possible by the pressure reducer. As a result, the total acting on the rotor or the element to be moved force due to the operation of the rotor is reduced as much as possible, which in turn leads to a reduced deflection of the rotor when the rotor is operated. If no deflection due to an existing contact bearing, such as a ball bearing, is allowed, the pressure on the bearing is reduced.

Preferably, the rotor is supported relative to the stator by a magnetic bearing, as exemplified in FIG 5 is shown. In 5 the two directions are axial 250 and radial 260 located. There is again a motor with a motor gap 40 , and the rotor is held axially with respect to the stator due to the permanent magnets on the rotor side and the electric coils on the side of the stator and not specifically regulated. In contrast, a radial detection device 270 and a radial control / regulation device 280 intended. The radial detection device 270 detects the position of the rotor with respect to the stator or vice versa via detection lines 271 , The result of radial detection 270 is via a sensor line 272 the radial control / regulation device 280 communicated. This generates corresponding actuator signals via Aktorsignalleitungen 273 on the rotor or the stator depending on the implementation. However, it is preferable to drive only the rotor to make it with respect to the stator due to the actuator signal 273 to position, such that the motor gap 40 around the entire rotor has a similar size and the rotor does not touch the stator.

At the in 5 In the embodiment shown, the rotor can be inside and the stator can be outside. Then it is an inner rotor. At the same time, however, the inner element may be the stator and the outer element may be the rotor, so that it is an external rotor. In principle, the magnetic bearing in both cases is similar in that an axial control does not take place, while a radial control by the radial detection device 270 and the radial controller 280 takes place.

6 shows a cross section through a preferred rotor, which is formed in several pieces. In particular, the rotor comprises the element to be moved 105 , which is formed in preferred embodiments of the present invention from a non-ferromagnetic material, such as plastic or aluminum. The element to be moved is here z. As a paddle wheel or impeller of a turbo compressor, as it can be used for example in a heat pump.

In contrast, the rotor 10 that is the permanent magnets 130 , the annular ones are the permanent magnets 130 surrounding return element and the above arranged bandage 170 formed of a different material than the element to be moved. In particular, the permanent magnets are formed of a specific material favorable for permanent magnets. The return element is annular and made of a ferromagnetic material and the bandage 170 is preferably formed of carbon material.

At the in 6 embodiment shown are the permanent magnets 130 partly over a first flat side 105a before, in the recess 40 is formed. The element to be moved 105 also has a second "flat" page 105b , which however has a smaller diameter than the first page 105a , which can also be seen as a "flat" side, if for purposes of illustration, the recess 40 is considered to be non-existent, and if further, the board in the form of an encircling spring 276 is also thought away. Preferably, however, engages the spring 276 in one in the inference element 160 provided annular groove 278 one, so the lead 276 and the groove 278 Take action. Depending on the embodiment, however, a spring and in the element to be moved can also be used in the return element 105 or in the first "flat" side 105a be provided the groove. Thus, the combination of return element, permanent magnet and bandage receives structural stability with the element to be moved 105 , so that a stable overall structure is created, which remains in shape and structure even at high speeds. In particular, through the recess 40 further ensures that the permanent magnets and the return element press due to the centrifugal forces on the rotor material, so that the connection between the return element on the one hand and the rotor material on the other hand, the tighter, the higher the speed.

With regard to the dimensions, it is preferred that the motor gap 40 is smaller than 1.5 mm, wherein in the case of encapsulation in the motor gap, the distance between the encapsulation material and the permanent magnet is less than 1.5 mm. Further, it is preferable that a diameter of the stator 20 is between 3 cm and 7 cm, or that a height of the stator is less than 4 cm. Further, the electric disk motor is configured to run at a speed greater than 50,000 revolutions per minute. Fern has the hole 200 a diameter preferably between 1 and 4 mm. There is also a margin 190 between the guide element 180 and the paddle wheel 105 preferably less than 1.5 mm.

In addition, it will, as in particular in 6 is shown, preferred that the element to be moved 105 the first "flat" page 105a that has the stator 20 opposite, and the second flat side 105b has that from the stator 20 facing away, wherein the diameter of the first flat side is greater than the second diameter of the second flat side. Further, as stated, the recess 40 in the first flat side 105a arranged, wherein the permanent magnets 130 at least partially in the recess 40 are localized. Further, in preferred embodiments, it is useful that the return element has the more trapezoidal cross-sectional shape as shown in FIG 6 is drawn, leaving a top edge of the inference element 160 is arranged higher in the axial direction than an upper edge of the permanent magnets 130 , This is the permanent magnets 130 placed as deep as possible in the recess, while the return element on the permanent magnets 130 on his side, with the bandage 170 connected, projects.

Furthermore, as it is clearer z. In 2 B shown is the encapsulation material 70 not only in the engine gap 40 on the stator 20 attached, but also on the bottom of the stator 20 in 2 B , that is the side of the stator, that of the recess 40 opposite. The stator 20 is preferably disc-shaped and has a normal, which is parallel to the axis of rotation or coincides with the axis of rotation. The flat side of the stator lies over the recess 40 a corresponding side of the element to be moved, and the encapsulation material 70 is also mounted on the flat side of the stator in addition to the corresponding sides of the permanent magnets. However, it is not necessary for the encapsulant to cover the entire area above the stator 20 fills. Instead, it is sufficient that the encapsulation material of the stator seals against the interior of the electric disc motor.

7 shows a preferred application of the electric disc motor on the example of a heat pump. The heat pump includes an evaporator 300 , a compressor 400 and a liquefying 500 , where the compressor 400 having the electric disc motor, the reference to the 1A to 6 has been described. In addition to the elements of the disc motor, for example, referring to FIG 2A have been shown, the compressor further comprises a Leitraum 510 which is arranged radially to that of the element to be moved 105 funded working steam coming from the evaporator 300 has been sucked in, continue to promote and ultimately the pressure to the required pressure in the condensation zone in the condenser 500 to increase.

Liquid to be cooled passes through an evaporator inlet 302 in the evaporator. Cooled working fluid passes through an evaporator outlet 304 again from the evaporator. To make sure the radial wheel 105 only steam and not water drops sucks, is also a mist eliminator 306 intended. Due to the low pressure in the evaporator 300 becomes part of the over the evaporator feed 302 in the evaporator 300 brought working fluid evaporated and through the mist eliminator 306 through the second page 105b of the radial wheel 105 sucked and conveyed up and then into the Leitraum 510 issued. From the Leitraum 510 becomes compressed working steam in the condensation zone 510 brought. The condensation zone 510 is also via a condenser feed 512 supplied to be heated working fluid, which is heated by the condensation with the heated steam and a Verflüssigerablauf 514 is dissipated. Preferably, the condenser is designed as a condenser in the form of a "shower", so that via a distribution device 516 a liquid distribution in the condensation zone 510 is reached so that the compressed working steam is condensed as efficiently as possible and the heat contained in it is transferred into the liquid in the condenser.

At the in 7 embodiment shown forms the motor housing 110 at the same time the upper housing part of the condenser or condenser 500 , In addition, as it is further in 7 shown is the connecting cable 80 for the coils of the stator 20 with a controller 600 connected to perform the appropriate speed controls and at the same time the active storage on a preferably used magnetic bearing, as shown by the 5 has been described. The controller thus also provides the functions of radial detection 270 and the radial control / regulation 280 ready.

Although certain elements are described as device elements, it should be understood that this description is likewise to be regarded as a description of steps of a method and vice versa.

Furthermore, it should be noted that the control, for example, by the element 600 in 7 or 280 in 5 can be implemented as software or hardware. The implementation of the controller may be on a non-volatile storage medium, a digital or other storage medium, in particular a floppy disk or CD with electronically readable control signals, which may interact with a programmable computer system such that the corresponding method of pumping heat or operating a heat pump is running. In general, the invention thus also comprises a computer program product with a program code stored on a machine-readable carrier for carrying out the method when the computer program product runs on a computer. In other words, the invention can thus also be realized as a computer program with a program code for carrying out the method when the computer program runs on a computer.

LIST OF REFERENCE NUMBERS

10

rotor

20

stator

30

motor gap

40

recess

50

first area

60

second area

70

encapsulant

80

connecting cables

90

Inlet / headwaters

100

Outlet / target area

105

moving element

105a

first page

105b

second page

110

motor housing

120

poetry

130

permanent magnets

140

pressure reducer

140a

first flow resistance

140b

second flow resistance

150

stator coils

160

Return element

170

bandage

180

management component

190

scope

200

drilling

210A-210d

construction elements

212a-212d

construction elements

250

axially

260

radial direction

270

Radial detector

271

sense line

272

control line

273

actuator cable

276

head Start

278

groove

280

Radial-control / regulation

300

Evaporator

302

evaporator feed

304

evaporator flow

306

Droplet

400

compressor

410

route

500

condenser

510

condensation zone

512

Verflüssigerzulauf

514

Verflüssigerablauf

516

Verflüssigerverteiler

600

control

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2549113 A2 [0002]

Cited non-patent literature

• Dissertation ETH No. 12870, "The bearingless disk motor", N. Barletta, 1998 [0003]

Claims (25)

Electric disc motor having the following features: a rotor ( 10 ), which is an element to be moved ( 105 ) having; a stator ( 10 ), wherein the stator is so with respect to the rotor ( 20 ) is arranged that a motor gap ( 30 ) is present between the rotor and the stator, wherein the rotor ( 10 ) a recess ( 40 ), in which the stator ( 20 ) is arranged, wherein the rotor ( 10 ) in a first area ( 50 ) is arranged with a first pressure, wherein the stator ( 20 ) in a second area ( 60 ) is arranged at a second pressure, wherein the second pressure is different from the first pressure, and wherein in the motor gap ( 30 ) an encapsulation material ( 70 ) through which the first area ( 50 ) from the second area ( 60 ) is disconnected. Electric disc motor according to claim 1, further comprising: a motor housing ( 110 ), with which the encapsulating material ( 70 ) is connected directly or indirectly, so that within the motor housing, the first region with the first pressure and outside the motor housing, the second region is formed with the second pressure. Electric disc motor according to claim 1 or 2, wherein the stator ( 20 ) a plurality of coils ( 150 ), which are connected to connecting lines ( 80 ) and which are applied to poles, the encapsulating material ( 70 ) the spools ( 150 ) and the poles surrounds, and wherein the connecting lines ( 80 ) from the encapsulating material ( 70 ) into the second area ( 60 ) protrude. Electric disc motor according to one of the preceding claims, which is operable so that the first pressure is less than the second pressure. Electric disc motor according to one of the preceding claims, in which the rotor is actively magnetically supported radially relative to a rotational axis of the rotor ( 270 . 280 ). Electric disc motor according to one of the preceding claims, in which the rotor is axially movable with respect to a rotational axis of the rotor ( 10 ) is magnetically passive. Electric disc motor according to one of the preceding claims, in which the rotor ( 10 ) at an inner area of the recess ( 40 ) a plurality of permanent magnets ( 130 ), further comprising an annular magnetic return element ( 160 ) the permanent magnets ( 130 ) so that the permanent magnets between the return element and the motor gap ( 30 ) are arranged. Electric disc motor according to claim 7, further comprising on the annular return element ( 160 ) a bandage ( 170 ) on the side of the inference element ( 160 ) attached to the permanent magnet ( 130 ) is turned away. Electric disc motor according to one of the preceding claims, in which the stator ( 20 ) is disc-shaped and has a flat side whose normal is parallel to an axis of rotation or coincides with the axis of rotation, wherein the flat side of the stator of one side of the element to be moved ( 150 ), and wherein the encapsulating material ( 70 ) on the flat side of the stator ( 20 ) and on one end face of the stator, the permanent magnets ( 130 ) of the rotor ( 10 ) is arranged opposite, is arranged. Electric disc motor according to one of the preceding claims, in which the element to be moved ( 105 ) a first page ( 105a ), which is the stator ( 20 ) and a second page ( 105b ) facing away from the stator, wherein a first diameter of the first side is greater than a second diameter of the second side. Electric disc motor according to claim 10, in which in the first side ( 105a ) the recess ( 40 ) is arranged, in which the permanent magnets ( 130 ) are at least partially arranged, wherein the permanent magnets ( 130 ) on one of the stator ( 20 ) facing away from side with an annular return element ( 160 ) are provided. Electric disc motor according to claim 11, wherein the permanent magnets ( 130 ) at least partially via the first page ( 105a ), or wherein the annular return element ( 160 ) on the first page ( 105a ), or wherein the permanent magnets ( 130 ) a first length over the first side ( 105a ) protrude and the annular return element ( 160 ) by a second length greater than the first length, over the first side ( 105a ) protrudes. Electric disc motor according to one of claims 10 to 12, in which the first side ( 105a ) a lead ( 276 ) and an annular return element ( 160 ) a groove ( 278 ), which is formed around the projection ( 276 ) or in which the first page ( 105a ) has a groove and the annular return element ( 160 ) has the projection, wherein the projection is formed to engage the groove. Electric disc motor according to one of the preceding claims, in which a motor housing ( 110 ) has a cover, with which the stator ( 20 ) and the encapsulating material ( 70 ) or in which the lid is made of the encapsulating material in one piece, or wherein the lid is detachably connected to a motor housing part, and wherein at an interface between the lid and the motor housing part a seal ( 120 ) through which the first area ( 50 ) from the second area ( 60 ) is sealed. Electric disc motor according to one of the preceding claims, in which the element to be moved ( 105 ) is a radial impeller with vanes, the vanes being configured to deliver gas to a third region of higher pressure than the first pressure upon rotation of the radial impeller. Electric disc motor according to claim 15, in which the encapsulating material ( 70 ) is arranged so that the third area communicates with the first area, and that the first area and the third area do not communicate with the second area. Electric disc motor according to one of the preceding claims, which is designed such that the motor gap ( 30 ) is smaller than 1.5 mm, or in which a diameter of the stator ( 20 ) is between 3 cm and 7 cm, or at which a height of the stator ( 20 ) is less than 4 cm, or is designed to run at a speed greater than 50,000 rpm. Electric disc motor according to one of the preceding claims, in which the rotor ( 10 ) with the element to be moved ( 105 ), wherein the element to be moved is made of aluminum or plastic, and the rotor ( 10 ) Permanent magnets ( 130 ) and a magnetic return element ( 160 ) having. Electric disc motor according to one of the preceding claims, which is designed to move a medium from a source region through the element to be moved ( 90 ) into a target area ( 100 ), whereby the pressure in the target area ( 100 ) higher than a pressure in the source area ( 90 ), wherein the electric disc motor further comprises the following feature: a pressure reducer ( 140 ) for reducing a pressure acting on the rotor due to an operation of the rotor ( 10 ). Electric disc motor according to claim 19, in which the pressure reducer ( 140 ) a first finite flow resistance ( 140a ) between the target area ( 100 ) and the motor gap ( 30 ) or a second finite flow resistance ( 140b ) between the motor gap ( 30 ) and the source area ( 90 ), wherein the first flow resistance ( 140a ) as a labyrinth seal ( 210a - 210c ) between a motor housing ( 110 ) and the rotor ( 10 ), or wherein the second flow resistance ( 140b ) as a bore ( 200 ) is formed in the rotor so that via the bore a gas communication between the source area ( 90 ) and the motor gap ( 30 ) is possible. Electric disc motor according to claim 20, wherein the bore ( 200 ) has a diameter between 1 and 4 mm. Electric disc motor according to one of the preceding claims, in which the element to be moved ( 105 ) is formed as a paddle wheel, which is connected to the rotor, wherein the element to be moved ( 105 ) further within a guide component ( 180 ) is rotatably arranged, with a margin ( 190 ) between the guide element ( 180 ) and the paddle wheel ( 105 ) is less than 1.5 mm. Heat pump with the following features: an evaporator ( 300 ); a compressor ( 400 ); and a liquefying ( 500 ), where the compressor ( 400 ) comprises an electric disc motor according to one of claims 1 to 22. Heat pump according to one of the preceding claims, wherein the element to be moved is a paddle wheel, wherein a suction region of the evaporator ( 300 ) with a guide component ( 180 ), so that during operation of the electric disc motor vaporized working fluid is sucked in, wherein in an operation of the heat pump, a swelling pressure in the intake of the evaporator ( 300 ) at a delivery end of the radial impeller is the first region having the first pressure higher than the source pressure, wherein in the condenser (in 500 ) is a condenser pressure which is greater than the first pressure, and wherein the second pressure in the second region ( 60 ) is equal to the condenser pressure or equal to an ambient pressure. Method for producing an electric disc motor with a rotor ( 10 ), which is an element to be moved ( 105 ), a stator ( 10 ), wherein the stator is so with respect to the rotor ( 20 ) is arranged that a motor gap ( 30 ) is present between the rotor and the stator, with the following steps: Running a recess ( 40 ) in the rotor ( 10 ), in which the stator ( 20 ), arranging the rotor ( 10 ) in a first area ( 50 ) with a first pressure; Arranging the stator ( 20 ) in a second area ( 60 ) with a second pressure, wherein the second pressure is different from the first pressure, and arranging encapsulating material ( 70 ) in the motor gap ( 30 ), through which the first area ( 50 ) from the second area ( 60 ) is disconnected.

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