Turbomachine

Abstract

The invention relates to a turbomachine, in particular a fan or compressor, comprising an impeller (3), a drive motor (4) having a stator (41) and a rotor (42), a drive shaft (5), and one or more main bearings (61, 62) designed as rolling bearings. The drive shaft (5) is used to transmit a rotational movement of the rotor (42) to the impeller (3) in order to thereby convey a fluid, in particular a gas. The main bearing(s) (61, 62) are used for radial and / or axial mounting of the rotor (42) and / or the drive shaft (5). The turbomachine also comprises at least one emergency bearing (71, 72) which is designed to assume the function of the main bearing(s) (61, 62) in the event of a fault. The invention further relates to a method for operating such a turbomachine and to a ventilator having such a turbomachine.

Description

[0001] TITLE

[0002] FLOW MACHINE

[0003] TECHNICAL AREA

[0004] The present invention relates to a turbomachine for drawing in and conveying a fluid, in particular a gas. The turbomachine can, for example, be used to generate a fluid flow, to extract fluid, and / or to generate positive or negative pressure. The invention also relates to a method for operating such a turbomachine and to a ventilator incorporating such a turbomachine.

[0005] STATE OF THE ART

[0006] Turbomachinery has been known for a long time and is used in a wide variety of applications. The turbomachinery covered by this patent has a typically electrically driven impeller that rotates within a housing. This draws in, compresses, and conveys a fluid. Depending on the type of turbomachine, the fluid can be, for example, a gas, such as air, or a liquid. If the fluid is a gas, the turbomachine is usually referred to as a fan or compressor. While fans achieve a pressure ratio between 1 and 1.3 between the intake and discharge sides, turbomachinery known as compressors achieves a pressure ratio greater than 1.3. In common parlance, fans and compressors are often also called blowers or fans.

[0007] Fluid machines in the form of fans and compressors are used especially for the ventilation of patients, such as in intensive care and emergency ventilation.

[0008] Turbomachinery has a limited lifespan because, sooner or later, certain components will show signs of fatigue, leading to performance losses, malfunctions, and ultimately, complete failure of the turbomachine. In turbomachinery, it is typically the rolling bearings that first show signs of damage and are thus impaired in their function. During operation, the rolling bearings provide radial and / or axial support for the rotor or an associated drive shaft. If the spreading damage remains undetected, it usually leads to total failure of the turbomachine.

[0009] In current technology, turbomachinery, particularly in critical applications such as intensive care and emergency medicine, is therefore replaced after operating times that are significantly shorter than the expected average lifespan. From an economic and sustainability perspective, this is unsatisfactory, as the turbomachinery could, in most cases, actually be used for much longer.

[0010] Chinese document CN 203362585 U proposes monitoring the condition of a radial bearing by measuring the bearing temperature using an infrared sensor through an observation port. This allows for the early detection of bearing damage.

[0011] EP 0536415 A1 discloses a fan which has a vibration sensor used to monitor the rolling bearings.

[0012] While the aforementioned sensors can monitor the condition of radial and axial bearings using current technology, they can only detect a bearing defect once it has already occurred. Depending on the type of bearing damage, a sensor may detect it before the bearing is completely defective. However, complete bearing failures that are not preceded by a gradual deterioration of bearing function cannot be prevented by a sensor. Furthermore, due to the installation situation, dynamic operation, and the small size of the bearings, reliable detection of bearing damage is often not possible. Therefore, the risk of a turbomachine failure due to a sudden bearing defect remains.

[0013] In machines with active magnetic bearings, it is known to provide emergency running bearings as a safeguard in case of a failure of the constant power supply. For example, CN 202273889 U discloses a fan with radial magnetic bearings as well as with protective bearings.

[0014] EP 2 390511 A1 discloses a shaft bearing with electromagnetic bearings and, for emergencies, permanent magnet bearings.

[0015] US Patent 2013 / 0207495 A1 describes an electric drive with active magnetic main bearings. Secondary bearings are provided to support the rotor if the corresponding main bearing fails. Since the secondary bearings are only designed for high rotational speeds, auxiliary bearings are also provided, which are used in the event of main bearing failure at low rotational speeds.

[0016] Furthermore, GB 1,031,948 discloses a fan driven by an internal combustion engine, in which a radial bearing is provided on the side of the impeller facing away from the engine, which is used in the event of a defect to prevent the impeller blades from hitting the flow housing.

[0017] PRESENTATION OF THE INVENTION

[0018] It is therefore an object of the present invention to provide a turbomachine which can be operated safely for as long as possible and / or in which a premature bearing failure does not immediately lead to a complete failure of the turbomachine.

[0019] To solve this problem, a turbomachine as specified in claim 1 is proposed. A method for operating such a turbomachine is specified in claim 13. Furthermore, a ventilator incorporating such a turbomachine is specified in claim 15. Advantageous embodiments are specified in the dependent claims.

[0020] The present invention therefore provides a turbomachine, in particular a fan or compressor, comprising

[0021] a balance bike;

[0022] a drive motor with a stator and a rotor;

[0023] a drive shaft for transmitting a rotary motion of the rotor to the impeller in order to convey a fluid, in particular a gas; and one or more main bearings designed as rolling bearings, which serve for the radial and / or axial support of the rotor and / or the drive shaft.

[0024] The turbomachine also has at least one emergency running bearing, which is designed to take over the function of the main bearing(s) in the event of a malfunction.

[0025] By having the emergency bearing(s) take over the function of the main bearing(s) in the event of a malfunction, the continued operation of the turbomachine can be ensured. The malfunction could, in particular, be a failure of one of the main bearings. Continuing operation even in the event of a malfunction is especially advantageous when the turbomachine is used for ventilation. Even when the turbomachine is used in other sectors, such as the food or pharmaceutical industries, for example, for cooling food or medicines, it can be a significant advantage if the turbomachine can continue operating for at least a period of time after a malfunction. With the help of the emergency bearing(s), such a failure can be avoided, and the turbomachine can continue to operate safely until a replacement and / or repair is carried out.Since the main bearing(s) designed as rolling bearings are generally particularly susceptible to damage, which can also occur at any time and without warning over a long period, the bearings or the turbomachinery in state-of-the-art systems often have to be replaced prematurely for safety reasons, especially when the actual service life of the turbomachine is far from being reached. However, by providing emergency running bearing(s), the turbomachine can be operated considerably longer and without the risk of total failure due to a malfunction of one or more of the main bearings. This allows the service life of the turbomachine to be extended considerably without compromising operational safety. The transfer of the function of the main bearing(s) to the emergency running bearing(s) is achieved through the use of the emergency running bearing(s).Replacing the main bearings with at least one emergency bearing in the event of a malfunction offers the further advantage that the need for replacement or repair is easier to determine. This can be achieved, for example, by measuring vibrations, which can change when the bearing function switches from the main bearing(s) to the emergency bearing. The change in vibrations can be detected, in particular, by means of a sensor. The fluid to be conveyed by the turbomachine can be, in particular, a gas, such as air. Since the turbomachine is preferably designed for use in ventilators, the gas to be conveyed can be, in particular, pure oxygen, a gas mixture with nitrogen and oxygen and possibly other substances, or oxygen-enriched air.In principle, the turbomachine could also be used, for example, to pump a liquid, such as water in particular.

[0026] The turbomachine is preferably a fan or compressor. In particular, it can be a radial turbomachine in which the fluid is drawn in axially, or parallel to a rotational axis defined by the impeller's movement, in the immediate vicinity of the impeller. In this case, the gas inlet is usually located near the rotational axis. In the radial turbomachine, the fluid flow is deflected by the rotation of the impeller, typically by 90°, and conveyed away from the impeller in an approximately radial, or more precisely, tangential direction, before being expelled through a gas outlet. In other words, the impeller can be designed, in particular, to deflect the fluid flow with respect to the rotational axis from an axial direction into an approximately radial or tangential direction.Radial turbomachines typically allow the generation of a relatively high pressure for a given volume of air. The impeller preferably has backward-curved blades. This enables particularly high pressures and high efficiency. However, it would also be possible for the turbomachine to be an axial turbomachine, in which the fluid flow is axial with respect to the axis of rotation, flowing into the casing and towards the impeller, and axially away from the impeller and out of the casing.

[0027] The flow machine can be specifically designed to support or take over a patient's breathing. If the patient's breathing is taken over by the flow machine, it is considered artificial ventilation; otherwise, it is respiratory support. It is also conceivable that the flow machine could be designed for use in a CPAP (Continuous Positive Airway Pressure) device.

[0028] The drive motor is preferably an electric motor with a stator that is stationary relative to the housing and a rotor that rotates during operation. The rotor preferably rotates around the axis of rotation of the impeller. The electric motor can, in particular, be a brushless DC motor.

[0029] The impeller can be manufactured as a single piece or in multiple pieces. It is preferably manufactured by injection molding, advantageously from a plastic material. Other manufacturing processes and materials are, of course, also possible. The impeller is typically fixed to the drive shaft, which in turn is usually fixed to the rotor of the drive motor. The drive shaft is preferably formed as a single piece and typically extends along the axis of rotation of the impeller. This axis of rotation generally defines a main longitudinal axis of the turbomachine, around which the rotor of the drive motor also advantageously rotates during operation.

[0030] The turbomachine preferably has a housing, which may in particular comprise a flow housing and a motor housing, wherein the flow housing forms a flow channel and the motor housing an interior space for arranging the drive motor. The flow housing also preferably forms the gas inlet and / or the gas outlet, wherein the gas inlet and the gas outlet are fluidically connected to each other by the flow channel. The flow channel preferably has at least a portion that extends annularly or spirally around the main longitudinal axis of the turbomachine. The flow housing also preferably forms an impeller chamber for arranging the impeller. The impeller chamber is preferably arranged radially within the annularly or spirally shaped portion of the flow channel.

[0031] According to a preferred embodiment, the flow housing is designed in two parts: a front section and a rear section, which together define the flow channel. This two-part design allows the flow housing to be easily opened to provide access to the impeller, for example, when it needs to be cleaned, especially sterilized, repaired, or replaced. The flow housing may have a wall that separates the impeller chamber from the motor compartment. The front section and / or the rear section of the flow housing is preferably manufactured as a single piece, advantageously from a plastic material, particularly by injection molding. A one-piece design of the flow housing is, of course, also possible.The motor housing can have cooling fins on its outer surface for the passive or active dissipation of heat energy from the engine compartment, compression heat from the turbomachine, and / or flow losses. According to a preferred embodiment, the motor housing is designed in two or more parts, comprising a front and rear section. This two-part design allows the motor housing to be easily opened to access the engine compartment, for example, when the drive motor needs to be repaired or replaced. Preferably, a circuit board with a motor controller is arranged in an interior space, particularly within the engine compartment, of the motor housing. This controller is also preferably easily accessible due to the two-part design of the motor housing, facilitating simple repair or replacement. The front and / or rear sections of the motor housing are preferably formed as a single piece.

[0032] Rolling bearings are bearings in which rolling elements between an inner and outer ring reduce frictional resistance. These rolling bearings can be, for example, ball bearings or cylindrical roller bearings. Due to their widespread use and frequent applications, rolling bearings are readily available and inexpensive, and are particularly advantageous with regard to minimal rolling resistance. However, they suffer from the problem already mentioned in the introduction: they can malfunction or even fail completely due to aging and wear. This is difficult to predict in terms of timing and can vary considerably from one turbomachine to another. The malfunction can be caused, for example, by gradual or rapid contamination or thermal overload of the rolling bearing.The present invention with the at least one emergency running bearing therefore offers considerable advantages with regard to main bearings which are designed in the form of rolling bearings.

[0033] The main bearings are radial and / or axial bearings, meaning they support the drive shaft and / or rotor in the radial and / or axial direction relative to the drive shaft's axis of rotation, and thus generally to the main longitudinal axis of the turbomachine. The main bearing(s) therefore surround the drive shaft and / or rotor radially, preferably completely. Alternatively or additionally, one or more axial bearings may be provided to support the drive shaft and / or rotor axially as well, that is, to brace it against the housing. The axial bearing(s) may also be designed as rolling bearings, or they may be, for example, plain bearings.

[0034] The emergency running bearing(s) is preferably designed to take over the function of the main bearing(s) in the event that one or more of the main bearings malfunction or even fail completely. The emergency running bearing(s) are preferably radial bearings, meaning that they each support the drive shaft and / or the rotor in the radial direction to the axis of rotation of the drive shaft and thus generally to the main longitudinal axis of the turbomachine. The emergency running bearing(s) therefore preferably surround the drive shaft and / or the rotor in the radial direction, preferably completely. Alternatively or additionally, the emergency running bearing(s) can also be in the form of axial bearings, meaning that they each support the drive shaft and / or the rotor in the axial direction to the axis of rotation of the drive shaft and thus generally to the main longitudinal axis of the turbomachine.

[0035] In principle, at least one emergency running bearing can be any type of bearing. For example, it is conceivable that the at least one emergency running bearing could be a rolling bearing, such as a ball bearing, or a gas bearing. According to a particularly preferred embodiment, however, the at least one emergency running bearing is designed as a plain bearing. Designing the emergency running bearing(s) as plain bearings is particularly simple and cost-effective to manufacture. Plain bearings are also generally less susceptible to failure even under less than ideal conditions, which is a considerable advantage in emergency operation, since the running of the drive shaft or rotor may not be smooth in this case and may be accompanied by vibrations, for example. With the help of the plain bearing(s), operation can continue and be ensured even in this case, at least for a certain period of time.

[0036] The emergency running bearing(s), designed as plain bearings, preferably each have a low-friction inner surface around its circumference. This allows the drive shaft and / or rotor to slide with low friction within the bearing. The inner surfaces of the plain bearing(s) can also have a friction-reducing coating, or the base material of the plain bearing can be impregnated with friction-reducing oil or be designed as a composite material with friction-reducing components. Compared to other drive shaft penetrations in the turbomachine, the emergency running bearing(s) are preferably robustly designed, which can be achieved, for example, by using a suitable material thickness and / or material selection. The emergency running bearing(s) are thus suitable for absorbing the often increased forces encountered during emergency operation.

[0037] According to a particularly preferred embodiment, the at least one emergency running bearing has a larger inner diameter than the main bearing(s). During normal operation, when the drive shaft and / or the rotor is radially supported by the main bearing(s), the at least one emergency running bearing is not used. Therefore, during normal operation, the at least one emergency running bearing does not come into contact with the drive shaft or the rotor, thus preventing unnecessary friction losses and wear on the emergency running bearing(s). However, as soon as one or more of the main bearings malfunction and the radial support and thus positioning by the main bearing(s) is no longer guaranteed, the drive shaft or the rotor usually no longer runs smoothly and / or centered on the main longitudinal axis. As a result, the drive shaft and / or the rotor automatically comes into contact with the emergency running bearing(s), which then...Continue to mount it radially.

[0038] Preferably, the turbomachine has exactly two main bearings, each of which is assigned at least one, and advantageously exactly one, emergency running bearing. By means of two main bearings or emergency running bearings, which can in particular each be designed as radial bearings, the drive shaft can be radially supported with a particularly effective and relatively low effort, ensuring smooth running along its entire length. Alternatively, however, it is also conceivable that only a single emergency running bearing is provided, which can in particular be positioned at a location where a failure is considered particularly likely.

[0039] The emergency running bearing(s) are preferably arranged axially on the drive shaft such that the main bearing(s) are located axially between the rotor and one of the emergency running bearings. In the event of a failure or malfunction, the function of the main bearing(s) is thus directly taken over by a corresponding emergency running bearing.

[0040] The emergency running bearing(s) are preferably arranged axially directly adjacent to the main bearing(s). This means that no further functional element is arranged axially between the emergency running bearing and the main bearing. Preferably, the main bearing and the respective emergency running bearing are even directly adjacent to each other in the axial direction. In the event of a failure of a main bearing, the support function is thereby taken over by the corresponding emergency running bearing, which is particularly well suited with regard to its positioning along the main longitudinal axis.

[0041] According to a further development of the invention, the rotor is formed by a permanent magnet, and the emergency running bearing, or one of the emergency running bearings, forms a sliding surface which allows the rotor to slide in the event of a malfunction. The corresponding emergency running bearing preferably has a slightly larger inner diameter than the outer diameter of the rotor. Providing an emergency running bearing designed as a sliding bearing in the rotor area has the advantage that no additional space is required along the main longitudinal axis for arranging the emergency running bearing(s). Furthermore, due to the weight ratios of the drive shaft and the rotor, the location in the rotor area can be very well suited for radial bearing arrangement.

[0042] In a preferred embodiment, the turbomachine has a flow housing that forms a flow channel, wherein, during operation, the fluid is drawn into the flow channel by the impeller and conveyed out of the flow housing through it. According to a particularly preferred embodiment, the flow housing forms or supports the emergency running bearing or one of the emergency running bearings. By forming or supporting the emergency running bearing or one of the emergency running bearings with the flow housing, it can be arranged at a relatively large distance from the rotor and / or from another emergency running bearing, thereby achieving an effective reduction in the load on the emergency running bearing. The corresponding emergency running bearing can be formed or supported by the flow housing in the axial direction on the side of the impeller facing away from the drive motor or on the side facing the drive motor.

[0043] If the emergency running bearing is formed or held by the flow housing on the side of the impeller facing away from the drive motor, the emergency running bearing is preferably arranged axially at the level of a central inlet opening of the flow housing, through which the fluid is drawn into the flow channel. The emergency running bearing can then be formed or held, for example, by struts extending in a radial or oblique-radial direction and, if applicable, by a ring attached to the radially inner end of the struts.

[0044] According to a further development of the invention, the turbomachine also has at least one sensor for detecting emergency running. Since the bearing function is taken over by the emergency running bearing(s) during emergency running, it is relatively easy to detect the emergency running condition in various ways using one or more sensors. Upon detection of emergency running, the repair or replacement of the turbomachine or just the affected main bearing(s) can then be initiated.

[0045] The sensor can, for example, be designed to detect mechanical vibrations and, in particular, as a MEMS sensor. Alternatively or additionally, a sensor can be provided for emergency running detection, which is designed for the electrical detection of contact between the rotor or drive shaft and at least one emergency running bearing. Alternatively or additionally, a change in the inductance or capacitance of the relevant components can also be used to detect emergency running. Furthermore, an alternative or equivalent sensor can be provided that is designed to detect increased power consumption by the drive motor.According to a further alternative or additional variant, a sensor may be provided that is designed to detect excessive heating in the area of ​​the at least one emergency running bearing, and / or a sensor may be provided that is an optical sensor for monitoring the radial and / or axial position of the rotor or the drive shaft. As a further alternative or additional variant, a sensor may be provided that is designed to detect a change in the electrical impedance of the at least one emergency running bearing. The latter sensor may alternatively or additionally also be designed to detect a change in the electrical impedance of one or more main bearings.

[0046] The present invention also relates to a method for operating a turbomachine designed according to the above embodiments, wherein continuous or at least regular monitoring is carried out during operation to determine whether the turbomachine is in a normal state in which the rotor or the drive shaft is supported radially and / or axially in the main bearing(s) as intended, or whether the turbomachine is in an emergency running state in which the rotor or the drive shaft is supported at least partially radially and / or axially in the at least one emergency running bearing.

[0047] Monitoring can be carried out using human sensory perception. For example, sound emissions during the operation of the turbomachine can be checked using hearing, and a change in these emissions can indicate an emergency running condition. Alternatively, vibrations and / or heat generation occurring during operation can be checked for changes using the sense of touch. However, according to a particularly preferred embodiment, monitoring is carried out using technical means, such as a sensor. The sensor(s) can have different designs, as already described above.

[0048] Upon detection of the emergency running condition, a signal is preferably generated, which can be, in particular, an acoustic and / or visual signal. Alternatively or additionally, a machine-readable signal can also be generated, which can be recognized and processed, for example, by a control unit. Based on the signal, the operator of the turbomachine knows that a replacement or repair of one or more of the main bearings or of the entire turbomachine is necessary, whereby the turbomachine can continue to be operated safely until the replacement or repair is carried out, thanks to the emergency running bearing(s). Depending on the embodiment, the sensor can also be implemented by a control unit that monitors a measured variable, such as the current consumption of the drive motor, and detects an emergency running condition based on deviations.

[0049] The invention further relates to a ventilator for supporting the respiration of a human or animal patient, comprising a flow machine designed according to the above description. The ventilator can serve only to partially support the patient's spontaneous breathing or it can be used as a replacement in cases of insufficient or absent spontaneous breathing.

[0050] BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Preferred embodiments of the invention are described below with reference to the drawings, which serve only for illustration and are not to be interpreted restrictively. The drawings show:

[0052] Fig. 1 shows a perspective view of a turbomachine according to the invention in the form of a radial fan according to a first embodiment;

[0053] Fig. 2 shows a central cross-sectional view onto the plane 11-11 through the turbomachine of Fig. 1;

[0054] Fig. 3 shows a perspective view of a turbomachine according to the invention in the form of a radial fan according to a second embodiment.

[0055] Fig. 4 shows a central cross-sectional view onto the plane Ill-Ill through the turbomachine of Fig. 3;

[0056] Fig. 5 shows a central cross-sectional view of a turbomachine according to the invention in the form of a radial fan according to a third embodiment; as well as

[0057] Fig. 6 shows a central cross-sectional view of a turbomachine according to the invention in the form of a radial fan according to a fourth embodiment.

[0058] DESCRIPTION OF PREFERRED EXECUTION FORMS

[0059] Figures 1 to 6 show various embodiments of the turbomachinery according to the invention in different views. The turbomachinery shown in the figures is a radial fan. However, the invention is not limited to radial fans; it encompasses any turbomachine, including axial fans. Features with the same or similar function and effect are identified by the same reference numeral in the different embodiments.

[0060] Figure 1 shows a first embodiment of a turbomachine according to the invention in the form of a radial fan. From the outside, the turbomachine essentially consists of a flow housing 1 and a motor housing 2. The flow housing 1 has a flow housing front section 11 and a flow housing rear section 12, which are preferably each manufactured as a single piece from a plastic material. They can be manufactured, in particular, by injection molding. The flow housing front section 11 and the flow housing rear section 12 together define a spirally extending flow channel 13 inside the flow housing 1, which is visible in Figure 2. The flow housing front section 11 forms a centrally arranged intake nozzle 17, which surrounds an inlet 18 through which air is drawn in axially from the outside into the flow channel 13 during operation.Radial webs 14 can be provided within the intake port 17 (see Figures 3 and 4). After flowing through the flow channel 13, the conveyed air passes through an outlet 16 in a radial (or more precisely, tangential) direction back to the outside. The outlet 16 is surrounded by a discharge port 15, which is formed jointly by the front part 11 and the rear part 12 of the flow housing.

[0061] The discharge nozzle 15 is designed on its outer side for coupling a gas or fluid line. For example, in a preferred embodiment, an air line belonging to a ventilator can be coupled, which indirectly connects the turbomachine to a breathing mask for ventilating a patient. The ventilator can be, in particular, a ventilator for supporting or taking over the respiration of a human or animal patient in intensive care and emergency medicine. The intake nozzle 17 can also be designed on its outer side for coupling an air, gas, or fluid line in order to draw the air, gas, or fluid through the line to the inlet 18.

[0062] To convey the air drawn in through the inlet 18, an impeller 3 is arranged inside the flow casing 1. During operation of the turbomachine, the impeller 3 rotates, thereby drawing air, or alternatively any gas or fluid, through the inlet 18 into the flow channel 13, compressing it there, and conveying it back out through the outlet 16. The rotational movement of the impeller 3 defines a principal longitudinal axis of the turbomachine.

[0063] The impeller 3 has a substantially circular base plate 31 that is slightly curved forward, i.e., towards the inlet 18. A plurality of impeller blades 32 are integrally formed at regular intervals on the front of this base plate. These blades serve to convey the aspirated fluid during operation. The impeller 3 has a through opening in its central center, which serves to attach the impeller 3 to a drive shaft 5. The impeller 3 is attached to the drive shaft 5 via a hub 33, with the impeller 3 being rotationally fixed to the hub 33, and the hub 33 being rotationally fixed to the drive shaft 5. The impeller 3 is preferably, but not necessarily, manufactured as a single piece and, in particular, preferably, but also not necessarily, by injection molding from a plastic material.

[0064] The drive shaft 5 extends along the main longitudinal axis of the turbomachine and serves to transmit a rotary motion caused by a drive motor 4 to the impeller 3.

[0065] The drive motor 4, located inside the motor housing 2, serves to set the drive shaft 5, and with it the impeller 3, into a rotary motion. The drive motor 4 is preferably a brushless DC motor comprising a stator 41 and a rotor 42, as can be seen in Figure 2. The rotor 42 is fixed to the drive shaft 5.

[0066] The control of the drive motor 4 is preferably integrated, for example, in the form of a microchip in a circuit board 81, which, like the drive motor 4, is located inside the motor housing 2.

[0067] The motor housing 2 has a rear motor housing section 22, which is arranged at the rear of the flow housing 1 and forms the rear of the turbomachine. At the front, the motor housing 2 is closed off by a front motor housing section 21, which, together with the rear motor housing section 22, defines an interior space within the motor housing 2. The drive motor 4 and, preferably, the circuit board 81 are arranged within the interior space of the motor housing 2. The front motor housing section 21 separates the interior space of the motor housing 2 from the interior space of the flow housing 1, in which the impeller 3 is located.

[0068] The motor housing 2 is attached to the flow housing 1, for example, by means of a threaded engagement or a bayonet coupling. To seal the motor housing 2 and the flow housing 1 against each other from the outside, sealing rings 9 are provided in the area of ​​the connection between these two housings.

[0069] For radial support of the drive shaft 5, a first main bearing 61 and a second main bearing 62 are provided, arranged on both sides of the drive motor 4. The main bearings 61 and 62 are rolling bearings of a known design. In addition to radial support, the main bearings 61 and 62 can also serve for axial support of the drive shaft 5.

[0070] To take over the function of one or both of the main bearings 61, 62 in the event of a malfunction or failure, the turbomachines shown in Figures 1 to 6 each have one or two emergency running bearings 71, 72. The emergency running bearings 71, 72 are preferably plain bearings. In the embodiment of Figure 2, a first emergency running bearing 71 is arranged directly adjacent to the first main bearing 61 on the impeller side and is held circumferentially by the motor housing 2, in particular by the front part 21 of the motor housing. A second emergency running bearing 72 is arranged directly adjacent to the second main bearing 62 on the side facing away from the drive motor 4, and this emergency running bearing 72 is held circumferentially by the motor housing 2, in particular by the rear part 22 of the motor housing.

[0071] In the event of a failure of one or both of the main bearings 61, 62, their function is thus directly taken over by one or both of the emergency running bearings 71, 72. To ensure that they are only activated when a failure occurs, the emergency running bearings 71, 72 preferably have a slightly larger inner diameter than the main bearings 61, 62. While the friction generated during rotation and, consequently, the energy consumption of the drive motor 4 may be increased during emergency running, and the running of the drive shaft 5 may be slightly less smooth, the basic function of the turbomachine can still be guaranteed until the main bearings 61, 62 or the entire turbomachine can be replaced or repaired. An unexpected, sudden failure of the turbomachine can thus be avoided in any case.

[0072] The two emergency running bearings 71, 72 thus serve here in particular for the radial (emergency) support of the drive shaft 5. As can be seen in the present embodiment of Figure 2 with regard to the emergency running bearing 71 (flange-like projection in the axial direction towards the main bearing 61), one or both of the emergency running bearings 71, 72 can additionally or alternatively serve for the axial emergency support of the drive shaft 5 in addition to the radial emergency support.

[0073] To detect an emergency running condition and initiate appropriate measures, such as replacement or repair, the turbomachine in all embodiments shown in Figures 1 to 6 has a sensor 82. The sensor 82, which is shown only schematically in Figures 2 to 6, can, for example, be designed to detect mechanical vibrations and, in particular, as a MEMS sensor. Since a mechanical vibration generated by the movement of the drive shaft 5 can be in the form of a sound audible or inaudible to the human ear, the sensor 82 designed to detect mechanical vibrations could also be a microphone.Alternatively or additionally, a sensor 82 may be provided for the electrical detection of contact or proximity, in particular intermittent proximity, between the drive shaft 5 (or, in the embodiment of Figure 5, the rotor 42) and the at least one emergency running bearing 71 or 72. In this case, the sensor 82 could, for example, be configured to detect whether an electric current is conducting from the drive shaft 5 (or the rotor 42) to the at least one emergency running bearing 71, 72. Alternatively or additionally, a sensor 82 may also be provided for the detection of increased power consumption by the drive motor 4 or excessive heating in the area of ​​the at least one emergency running bearing 71, 72. In this case, the sensor 82 could, for example, be configured to measure the current consumption of the drive motor 4, or the sensor 82 could be a thermometer.Alternatively or additionally, a sensor 82 may also be present, which is an optical sensor for monitoring the radial position of the rotor 42 and / or the drive shaft.

[0074] In the embodiments shown in Figures 1 to 6, the sensor 82 is arranged on the rear side of the motor housing rear section 22. Although this is a preferred positioning of the sensor 82 in many cases, it can of course also be arranged at any other position on the turbomachine, depending on the design, measuring method, construction and / or application.

[0075] For power supply and / or data transmission, the sensor 82 is provided with a cable connection 83, which is shown schematically in the figures. The sensor 82 can be connected, in particular, to a control unit, e.g., provided on the circuit board 81, which evaluates the measured values ​​determined and transmitted by the sensor and generates a corresponding alarm signal upon detection of a fault. The alarm signal can be, in particular, an audible and / or visual signal perceptible to the user. Alternatively or additionally, upon detection of a fault, a central location can also be automatically notified, which may be located, for example, at the manufacturer or distributor of the turbomachine or ventilator, so that a replacement or repair can be initiated. Notification can be via cable or wirelessly, and in particular via a network.It is also possible to inform a higher-level device or control system about the transition to emergency mode and leave the correct reaction and forwarding of the signal to this higher-level system.

[0076] The embodiment shown in Figures 3 and 4 differs from that of Figure 2 in that it has only a single emergency running bearing 71, which is located in the area of ​​the inlet 18, i.e., within the intake manifold 17. Like the emergency running bearings 71 and 72 of Figure 2, the one in the embodiment shown in Figures 3 and 4 is also designed as a plain bearing. Here, the emergency running bearing 71 is fixed in a ring that is centrally located within the inlet 18 and held by the radial webs 14. The drive shaft 5 therefore extends somewhat further in the axial direction towards the inlet 18.

[0077] In the embodiment shown in Figure 5, in contrast to the embodiment shown in Figure 2, a single emergency running bearing 71 is also provided. This bearing surrounds the rotor 42, so that in the event of a failure of one or both of the main bearings 61, 62, the rotor 42 slides on the inside of the emergency running bearing 71, which is designed as a plain bearing. The rotor 42 is preferably designed as a permanent magnet, optionally with an additional coating. Reliable operation of the rotor 42 and the drive shaft 5 is thus still ensured even in the event of a failure of one or both of the main bearings 61, 62.

[0078] Finally, Figure 6 shows an embodiment with two emergency running bearings 71, 72, which are arranged similarly to, but somewhat differently from, the embodiment shown in Figure 2. The first emergency running bearing 71 is also located in the area between the first main bearing 61 and the impeller 3, but is held by the rear section 12 of the flow housing. In contrast to the embodiments shown in Figures 1 to 5, the rear section 12 of the flow housing here forms a partition wall towards the motor housing 2 on the rear side of the impeller 3. The first emergency running bearing 71 is located within this partition wall and is held by it. The second emergency running bearing 72 is located, as in the embodiment shown in Figure 2, on the side of the second main bearing 62 facing away from the drive motor 4, but here it is spaced slightly apart from the second main bearing 62. Here, too, the second emergency running bearing 72 is held circumferentially by the motor housing 2, in particular by the rear section 22 of the motor housing.

[0079] The invention is, of course, not limited to the embodiments shown in the figures, and a multitude of variations and modifications are possible. For example, the emergency running bearings 71, 72 of the various embodiments can also be exchanged and / or supplemented in any combination with respect to their positioning. The embodiments of Figures 3, 4, and 5 can therefore also have more than one emergency running bearing 71, and those of Figures 2 and 6 can accordingly have only one or more than two emergency running bearings. Furthermore, the emergency running bearing(s) 71, 72 need not necessarily be designed as plain bearings, but could, for example, also be designed as rolling bearings, such as a ball bearing, or as gas bearings, such as an aerostatic or aerodynamic bearing. One or more main bearings could also serve to support the rotor 42 instead of supporting the drive shaft 5.The turbomachine need not necessarily be used for conveying air. It could instead be used for conveying any other gas or fluid, such as a liquid. Furthermore, sensor 82 is not necessarily required, or it could be comprised of a multitude of sensors which, using the same or different measurement methods, work together to detect an emergency running condition. Numerous other modifications are conceivable. [REFERENCE SYMBOL LIST]

[0080] 1 Flow housing

[0081] 11 Flow housing front part

[0082] 12 Flow housing rear section

[0083] 13 Flow channel

[0084] 14 radial webs

[0085] 15 exhaust nozzles

[0086] 16 Outlet

[0087] 17 Intake manifolds

[0088] 18 Admission

[0089] 2 Motor housings

[0090] 21 Engine housing front part

[0091] 22 Rear of engine housing

[0092] 3 wheel

[0093] 31 Base plate

[0094] 32 wheel blades

[0095] 33 hub

[0096] 4 Drive motor

[0097] 41 Stator

[0098] 42 Rotor

[0099] 5 Drive shaft

[0100] 61 First Main Camp

[0101] 62 Second Main Camp

[0102] 71 First emergency running bearing

[0103] 72 Second emergency running bearing

[0104] 81 circuit board

[0105] 82 Sensor

[0106] 83 Cable connection

[0107] 9 sealing ring

Claims

PATENT CLAIMS 1. Turbomachine, in particular fan or compressor, comprising an impeller (3); a drive motor (4) with a stator (41) and a rotor (42); a drive shaft (5) for transmitting a rotary motion of the rotor (42) to the impeller (3) in order to convey a fluid, in particular a gas; and one or more main bearings (61, 62) designed as rolling bearings, which serve for the radial and / or axial support of the rotor (42) and / or the drive shaft (5); characterized by the fact that The turbomachine also has at least one emergency running bearing (71, 72) which is designed to take over the function of the main bearing(s) (61, 62) in the event of a malfunction.

2. Turbomachine according to claim 1, wherein the at least one emergency running bearing (71, 72) is designed as a sliding bearing.

3. Turbomachine according to claim 1 or 2, wherein the at least one emergency running bearing (71, 72) has a larger inner diameter than the main bearing(s) (61, 62).

4. Turbomachine according to one of the preceding claims, comprising exactly two main bearings (61, 62), each of which at least one emergency running bearing (71, 72) is assigned.

5. Turbomachine according to one of the preceding claims, wherein the emergency running bearing(s) (71, 72) are arranged axially on the drive shaft (5) such that the main bearing(s) (61, 62) are located in the axial direction between the rotor (42) and one of the emergency running bearings (71, 72).

6. Turbomachine according to one of the preceding claims, wherein the emergency running bearing(s) (71, 72) are arranged axially directly next to the main bearing(s) (61, 62).

7. Turbomachine according to one of the preceding claims, wherein the rotor (42) is formed by a permanent magnet and the emergency running bearing (71, 72) or one of the emergency running bearings (71, 72) forms a sliding surface which serves to slide the rotor (42) in the event of a malfunction.

8. Turbomachine according to one of the preceding claims, further comprising a flow housing (1) which forms a flow channel (13), wherein the fluid is drawn into the flow channel (13) by the impeller (3) during operation and conveyed out of the flow housing (1) through it, and wherein the flow housing (1) forms or holds the emergency running bearing (71, 72) or one of the emergency running bearings (71 , 72).

9. Turbomachine according to claim 8, wherein the flow housing (1) forms or holds the emergency running bearing (71) in the axial direction on the side of the impeller (3) facing away from the drive motor (4). 10 Turbomachine according to claim 9, wherein the flow housing (1) forms a central inlet opening (18) through which the fluid is drawn into the flow channel (13), and wherein the emergency running bearing (71) is arranged in the axial direction at the level of the inlet opening (18).

11. Turbomachine according to one of the preceding claims, further comprising at least one sensor (82) for detecting an emergency running condition.

12. Turbomachine according to claim 11, wherein the sensor (82) is designed for the detection of mechanical vibrations and in particular as a MEMS sensor, or wherein the sensor (82) is designed for the electrical detection of contact between the rotor (42) or the drive shaft (5) and the at least one emergency running bearing (71, 72), or wherein the sensor (82) is designed for the detection of increased power consumption by the drive motor (4) or excessive heating in the area of ​​the at least one emergency running bearing (71, 72) or a change in electrical impedance, or wherein the sensor (82) is an optical sensor for monitoring the radial and / or axial position of the rotor (42) or the drive shaft (5).

13. Method for operating a turbomachine designed according to one of the preceding claims, wherein continuous or at least regular monitoring is carried out during operation to determine whether the turbomachine is in a normal state in which the rotor (42) or the drive shaft (5) is supported radially and / or axially in the main bearing(s) (61, 62) as intended, or whether the turbomachine is in an emergency running state in which the rotor (42) or the drive shaft (5) is supported at least partially radially and / or axially in the at least one emergency running bearing (71, 72).

14. Method according to claim 13, wherein a signal is generated upon detection of the emergency running state.

15. Ventilator for supporting or taking over the breathing of a human or animal patient, comprising a flow machine according to any one of claims 1 to 12.

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