Gantry drive for a computed tomography device

Abstract

Gantry drive (10) for a computer tomography device, - wherein the gantry drive (10) comprises a double-controlled asynchronous machine and a tunnel-shaped cavity (40) for receiving a patient into the computed tomography device along a rotation axis (z) of the gantry drive (10), - wherein the asynchronous machine comprises a three-phase stator (50) and a three-phase rotor (60), wherein the three-phase rotor (60) is arranged in a ring around the rotation axis (z) of the gantry drive (10), wherein the three-phase stator (50) and the three-phase rotor (60) form a three-phase motor for providing a rotating field power, - wherein, by means of the rotating field power, on the one hand, a mechanical drive power for generating a rotary movement of the three-phase rotor (60) relative to the three-phase stator (50) about the rotation axis (z) of the gantry drive (10) can be provided and, on the other hand, an electrical supply power of a payload device can be provided and / or transmitted from the three-phase stator (50) to the three-phase rotor (60).

Description

[0001] The invention relates to a gantry drive and a computed tomography device with such a gantry drive.

[0002] Gantry drives for computed tomography devices or computed tomographs are generally known, for example from document EP 4 285 824 A1. A conventional gantry for a computed tomography device typically has two support rings arranged around a tunnel-shaped cavity. The two support rings are usually arranged to be rotatable relative to one another, such that one of the two support rings forms a stationary support ring and the other of the two support rings forms a rotating support ring. If an X-ray source and an X-ray detector are arranged on the rotating support ring, the rotating support ring is usually rotated around the cavity, typically with at least half a revolution, in particular with a plurality of revolutions in a rotary movement. A mechanical drive power is required to carry out the rotary movement.Basically, different variants of such gantry drives are known for transmitting the mechanical drive power used for the rotational movement of the rotating support ring.

[0003] In this context, it has become apparent that there is a need to provide an improved, or alternative, gantry drive. It is therefore an object of the present invention to provide an improved, or alternative, gantry drive. These and other objects, which will be mentioned upon reading the following description or which may be recognized by a person skilled in the art, are achieved by the subject matter of the independent claims. The dependent claims relate to embodiments of the invention. Regardless of the grammatical gender of a particular term, persons with male, female, or other gender identities are also included.

[0004] A first aspect of the present disclosure relates to a gantry drive for a computed tomography device, wherein the gantry drive comprises a double-controlled asynchronous machine and a tunnel-shaped cavity for receiving a patient in the computed tomography device along a rotational axis of the gantry drive, wherein the asynchronous machine comprises a three-phase stator and a three-phase rotor, wherein the three-phase rotor is arranged in a ring around the rotational axis of the gantry drive, in particular in a ring around the cavity, wherein the three-phase stator and the three-phase rotor form a three-phase motor for providing a rotating field power,wherein, by means of the rotating field power, on the one hand, a mechanical drive power for generating a rotary movement of the three-phase rotor relative to the three-phase stator about the rotation axis of the gantry drive can be provided and, on the other hand, an electrical supply power of a payload device can be provided and / or transmitted from the three-phase stator to the three-phase rotor.

[0005] A doubly controlled asynchronous machine can be used to generate torque and transmit power and can be integrated into a computed tomography device. In other words, a doubly controlled asynchronous machine can be used to generate a rotary motion of the three-phase rotor and to supply electrical power to a payload device. A payload device within a gantry drive is a device that requires an electrical (power) supply, such as electronic components such as emitters or detectors. It is conceivable that the payload device has a high-voltage generator and / or an X-ray source operable with an electrical supply power greater than 5 kW, in particular greater than 50 kW, preferably greater than 150 kW.For a further explanation of a payload device, reference is made to the disclosure of EP 4 285 824 A1, in particular to paragraphs

[0012] ,

[0013] ,

[0025] ,

[0029] ,

[0031] -

[0040] ,

[0057] ,

[0059] ,

[0061] ,

[0066] ,

[0070] -

[0073] ,

[0077] ,

[0086] -

[0093] ,

[0098] -

[0100] ,

[0103] ,

[0107] ,

[0108] and

[0109] of EP 4 285 824 A1. The disclosure of EP 4 285 824 A1 is hereby incorporated by reference.

[0006] It is further conceivable for the payload device to have at least one electronic component, such as at least one emitter and / or at least one detector. An asynchronous machine can be used as the main drive of a gantry drive, which can additionally enable energy transfer to the rotatable system part of the asynchronous machine. The gantry drive can be used in a computed tomography device. This asynchronous machine can be used to rotate an image plane. The present disclosure also encompasses the integration of an asynchronous machine into a gantry drive, which can act as a drive and as an energy transfer in a rotatable system part.

[0007] An asynchronous machine is a three-phase machine that can be used as a motor and a generator. An asynchronous machine can comprise a rotor and a stator. A stator can comprise three coils or a multiple thereof. In an asynchronous machine, a rotor can lead or lag a stator's rotating field. In an asynchronous machine, a rotor can be designed as a squirrel-cage or squirrel-cage rotor, although an asynchronous machine can be short-circuited. A rotor winding can be designed as a bar or coil winding. A rotor winding can be made of copper. A rotor can also be excited with an applied voltage, for example to change the electrical properties of the rotor. A gantry drive can comprise a converter, which can be a frequency converter, for example.

[0008] A variant of an asynchronous machine is a doubly controlled asynchronous machine, which can offer advantages over other asynchronous and synchronous machines. In a doubly controlled asynchronous machine, not only a stator but also a rotor can be controlled. This can be made possible by an additional phase tap, preferably on the rotating side. In a doubly controlled asynchronous machine, a rotor can supply and dissipate active and reactive power. In a doubly controlled asynchronous machine, the speed and / or reactive power can be controlled on the rotor side or rotor side via a converter. The converter can be a frequency converter. A doubly controlled asynchronous machine can be connected to a possible load, such as a network, a motor, a computed tomography device, an emission device and / or a detector, at a stator.A (frequency) converter can be used to control sinusoidal currents of variable frequency in a rotor circuit. A rotor cannot be connected directly, for example indirectly, to a load such as a grid, a motor, a computed tomography device, an emission device and / or a detector, because a rotor can be controlled via a (frequency) converter. A (frequency) converter can make a rotor voltage variable in frequency. This allows a speed to be varied and adjusted within a certain frequency range. A stator can be connected to a load such as a grid, a motor, a computed tomography device, an emission device and / or a detector, and can have a fixed stator voltage and stator frequency.

[0009] In a double-controlled asynchronous machine, a variable-frequency voltage can be applied to a rotor via a frequency converter. Depending on the excitation, the speed and / or reactive power consumption of the asynchronous machine can be varied.

[0010] Slip, which is explained below, can result from a difference between the stator frequency and the rotor frequency. The speed of an asynchronous motor can be set using the output frequency of a (frequency) converter. A maximum permissible electrical power must be observed for a speed. Slip can be related to the electrical power of a rotor. The magnitude of slip can affect the magnitude of electrical power. The setting of a speed can depend on a maximum electrical power or a permissible nominal load and can therefore be limited.

[0011] In doubly controlled asynchronous machines, slip power from the rotor circuit can be controlled via an inverter to a load, such as a grid, a motor, a computed tomography device, an emission device, and / or a detector. This situation is referred to as subsynchronous motor operation of an asynchronous machine. In subsynchronous operation, the speed of an asynchronous machine can be below a synchronous frequency. In this case, an asynchronous machine can be operated with positive slip. Excess active power from a rotor can be additionally controlled via a (frequency) converter.

[0012] In supersynchronous operation, the speed of an asynchronous machine can exceed a synchronous frequency. In this case, an asynchronous machine can be operated with negative slip. Additional active power can be supplied to a rotor via a (frequency) converter.

[0013] Double-controlled asynchronous machines have numerous advantages over synchronous machines and other asynchronous machines. Double-controlled asynchronous machines can, or rather must, be dimensioned larger than asynchronous machines, which are designed solely to provide mechanical torque or mechanical power, due to the additional power transmission to the rotating system section, which is possible with this drive technology. Due to their larger dimensions, double-controlled asynchronous machines can provide significantly higher power, for example, rotating field power, than other smaller asynchronous machines. Due to their larger dimensions, double-controlled asynchronous machines can, for example, provide more mechanical drive power to generate rotary motion of the three-phase rotor than other asynchronous machines.Due to their larger dimensions, doubly controlled asynchronous machines can accelerate a rotating support ring in a shorter time than other asynchronous machines or synchronous machines. Doubly controlled asynchronous machines can provide rotating field power for an electrical supply power to a payload device. In this case, an electrical supply power to a payload device is normally not necessary or only required to a limited extent during the acceleration phase of a computed tomography device, since a payload device is normally only used in a measuring phase. In an acceleration phase, a rotating support ring is normally accelerated up to an operating speed. In a measuring phase, a rotating support ring can normally rotate at a relatively constant speed.

[0014] Double-controlled asynchronous machines can be designed without slip rings and / or brushes, as the mechanical drive and energy transfer can be handled by the double-controlled asynchronous machine. This eliminates the need for maintenance and replacement of slip rings and / or brushes in double-controlled asynchronous machines. Slip rings and / or brushes can attract dirt and contaminants, such as abrasion, and cause wear, which can affect other areas of a machine that would require maintenance and cleaning. Furthermore, in double-controlled asynchronous machines, the space that would have been required for slip rings can be used for other purposes. The gantry drive of the present disclosure preferably does not include a slip ring and / or brush.

[0015] Preferably, the present disclosure comprises a dual-controlled asynchronous machine configured to control the three-phase stator and the three-phase rotor. This can occur both in the direction from the stationary to the rotating part and from the rotating to the stationary part of the asynchronous machine.

[0016] As described above, a doubly controlled asynchronous machine has numerous advantages due to its design. A doubly controlled asynchronous machine has the option of controlling both the three-phase stator and the three-phase rotor. The degree to which the three-phase stator and / or the three-phase rotor can be controlled can be regulated. The controlled supply can be provided for the three-phase stator and / or the three-phase rotor, whereby a basic power must be provided for the rotating part. The controlled supply can be provided continuously between the three-phase stator and the three-phase rotor in any ratio, minus a basic power for the rotating part.

[0017] Preferably, the gantry drive comprises a double-controlled asynchronous machine which is designed to provide the mechanical drive power for generating a rotary movement of the three-phase rotor and the electrical supply power of a payload device.

[0018] As described above, a doubly controlled asynchronous machine has numerous advantages due to its design. A doubly controlled asynchronous machine has the option of providing both the mechanical drive power to generate the rotary motion of the three-phase rotor and the electrical supply power to a payload device. The proportion of mechanical drive power and / or electrical supply power provided to a payload device can be regulated. The controlled supply can be provided for the mechanical drive power and / or the electrical supply power to a payload device, although a basic power must be provided for the rotating part.The controlled power supply can be provided continuously in any ratio between the mechanical drive power and the electrical supply power of a payload device, less a basic power for the rotating part.

[0019] Preferably, a gantry with a doubly controlled asynchronous machine has a higher integration density compared to the variant with synchronous machines and other asynchronous machines, since an additional power transmission path is eliminated. The positioning of the doubly controlled asynchronous machine described here allows the rear of the gantry to be either more compact and / or filled with other components, thereby increasing the functional density of the entire system.

[0020] Preferably, the gantry drive comprises a dual-controlled asynchronous machine configured to control a rotational speed and / or reactive power consumption of the gantry drive. The reactive power consumption is preferably as low as possible.

[0021] As described above, a double-controlled asynchronous machine offers numerous advantages due to its design. A double-controlled asynchronous machine has the ability to control both speed and reactive power consumption.

[0022] Preferably, the present disclosure includes a gantry drive including an energy buffer in the three-phase rotor.

[0023] An energy buffer offers a way to store or temporarily store energy for at least a certain period of time. This means that at least the required amount of energy does not have to be provided over the entire period. It is sufficient to provide the amount of energy that is needed on average over a certain period of time. If more energy is needed at times, this energy can be taken from the energy buffer. If less energy is needed than is provided at times, the energy buffer can be refilled or charged. An energy buffer can be a (temporary) storage device. An energy buffer can be a battery, for example. This makes it possible to reduce the required energy that is provided. This also makes it possible to reduce the maximum energy required, since the periods in which the maximum energy is required can be reached with energy from an energy buffer.

[0024] More than one energy buffer can be present in the three-phase rotor, preferably two to six, particularly preferably three to four. This allows the use of several smaller energy buffers, which can be more easily integrated into the three-phase rotor.

[0025] The gantry drive preferably comprises a dual-controlled asynchronous motor and a converter, in particular a frequency converter. A converter can be used to control, for example, sinusoidal currents and / or a voltage of variable frequency into the three-phase rotor. The use of a converter makes it possible to continuously adjust a speed within a speed range.

[0026] Preferably, the gantry drive comprises a double-controlled asynchronous machine, which, as described above, can have a positive or negative slip. The magnitude of the slip can, as described above, affect the magnitude of the electrical power.

[0027] Based on the characteristics of asynchronous machines, and especially of doubly controlled asynchronous machines, special features and challenges arise when integrating and using such asynchronous machines in a gantry drive. For example, such asynchronous machines require more installation space than other drive machines. Special features and challenges include the achievable air gap tolerance of the drive, the cooling situation, and the impact on other components of the drive and other components of adjacent elements that must be designed and / or arranged differently.

[0028] Preferably, the gantry drive comprises a stationary drive element, a rotatable drive element, a stationary bearing element and a rotatable bearing element, wherein the stationary drive element is arranged further away from the rotation axis of the gantry drive in the radial direction than the rotatable drive element.

[0029] A computed tomography device with a rotation axis can comprise a gantry drive, a stationary support ring, and a rotatable support ring, wherein the stationary support ring is connected to the three-phase stator and the rotatable support ring is arranged in a rotationally fixed manner relative to the three-phase rotor. The gantry drive comprises a stationary part, a rotatable part, and a load direction. The center of gravity of the rotatable support ring can be spaced from a bearing unit of the stationary support ring. The bearing unit comprises a stationary part and a rotatable part. The stationary support ring comprises a cooling channel from which cooling can be tapped.

[0030] The stationary drive element is preferably arranged further away from the rotation axis of the gantry drive in the radial direction than the rotatable drive element.

[0031] In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs orthogonally (radially) to the rotational axis of the computed tomography device. This arrangement cancels out the reluctance force occurring in the magnetic circuit between the rotating and stationary drive parts, particularly with a fully formed ring. This eliminates any additional axial loading of the bearing unit compared to the embodiments described below.

[0032] Cooling of the rotating and stationary windings is achieved either by convection through a tap into an adjacent cooling channel for air cooling of the rotating system component, or by heat conduction or induction of the adjacent bearing unit. In this configuration, heat is introduced evenly within the bearing unit, based on comparable losses in the stationary and rotating drive components. The reduction of any preload within the bearing unit due to different material expansions is thus avoided by design.

[0033] In the context of the air gap tolerance, the described embodiment in radial flow arrangement is disadvantageous compared to the axial flow arrangement described below, since in addition to concentricity tolerances, an offset of the running axes of the rotating and stationary system part, for example due to settling behavior, must also be taken into account.

[0034] Another advantage of this design is the small axial distance between the bearing unit and the center of gravity of the rotating system component. This minimizes the torque acting on the bearing unit.

[0035] Preferably, the gantry drive comprises a stationary drive element, a rotatable drive element, a stationary bearing element and a rotatable bearing element, wherein the stationary drive element is arranged next to the rotatable drive element in the radial direction from the rotation axis of the gantry drive, and wherein the stationary bearing element is arranged next to the rotatable drive element in the radial direction from the rotation axis of the gantry drive.

[0036] A computed tomography device with a rotation axis can comprise a gantry drive, a stationary support ring, and a rotatable support ring, wherein the stationary support ring is connected to the three-phase stator and the rotatable support ring is arranged in a rotationally fixed manner relative to the three-phase rotor. The gantry drive comprises a stationary part, a rotatable part, and a load direction. The center of gravity of the rotatable support ring is spaced from a bearing unit of the stationary support ring. The bearing unit comprises a stationary part and a rotatable part. The stationary support ring comprises a cooling channel from which cooling, preferably in the form of air cooling, can be tapped.

[0037] The stationary drive element is arranged next to the rotating drive element in the radial direction of the gantry drive's rotational axis. The stationary bearing element is arranged next to the rotating drive element in the radial direction of the gantry drive's rotational axis. In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs axially to the rotational axis of the computed tomography device. Due to this arrangement, the reluctance force occurring in the magnetic circuit between the rotating and stationary drive parts acts as an additional load on the bearing unit compared to the previous arrangement.

[0038] Cooling of the rotating and stationary windings is achieved either by convection through a tap into an adjacent cooling channel for air cooling of the rotating system component, or by heat conduction or induction from the adjacent bearing unit. In this configuration, heat input within the bearing unit is almost uniform, based on comparable losses in the stationary and rotating drive components. The loss of any preload within the bearing unit due to different material expansions is thus avoided by design.

[0039] In the context of air gap tolerance, the described embodiment in an axial flow arrangement has an advantage over the previously described radial flow arrangement because, in addition to the existing axial runout tolerances, an offset of the running axes of the rotating and stationary system components, for example, due to settling behavior, has no influence. Another advantage of this embodiment is the small axial distance between the bearing unit and the center of gravity of the rotating system component, which is kept small by the design. This minimizes the torque acting on the bearing unit.

[0040] Preferably, the gantry drive comprises a stationary drive element, a rotatable drive element, a stationary bearing element and a rotatable bearing element, wherein the stationary drive element is arranged next to the rotatable drive element in the radial direction from the rotation axis of the gantry drive, and wherein the stationary bearing element is arranged next to the stationary drive element in the radial direction from the rotation axis of the gantry drive.

[0041] The stationary drive element is arranged next to the rotating drive element in the radial direction of the gantry drive's rotation axis. The stationary bearing element is arranged next to the stationary drive element in the radial direction of the gantry drive's rotation axis.

[0042] In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs axially to the rotational axis of the computed tomography device. Due to this arrangement, the reluctance force occurring in the magnetic circuit between the rotating and stationary drive parts acts as an additional load on the bearing unit compared to the above arrangement.

[0043] Cooling of the rotating and stationary windings is achieved either via convection by tapping into an adjacent cooling channel for air cooling of the rotating system component, or via heat conduction or conduction of the adjacent bearing unit. Compared to the above arrangements, the cooling effect of the rotating assembly is maximized via conduction, as the heat sink and the associated connection are larger. A negative aspect of this arrangement is the uneven heat input within the bearing unit due to the component spacing. The loss of any preload within the bearing unit due to varying material expansion must therefore be taken into account.

[0044] In the context of the air gap tolerance, the described embodiment in axial flow arrangement has an advantage over the radial flow arrangement described above, since in addition to the existing axial runout tolerances, an offset of the running axes of the rotating and stationary system part, for example due to settling behavior, has no influence.

[0045] A further disadvantage of this design is the increased axial distance between the bearing unit and the center of gravity of the rotating system component compared to the above arrangements. This further increases the torque acting on the bearing unit.

[0046] The present disclosure also relates to a computed tomography device comprising a gantry drive disclosed above, a stationary support ring, and a rotatable support ring, wherein the stationary support ring is connected to the three-phase stator and the rotatable support ring is arranged in a rotationally fixed manner relative to the three-phase rotor.

[0047] A further aspect of the present disclosure relates to a method for generating a rotary movement of a three-phase rotor by means of a gantry drive described above, comprising the following steps: providing a rotating field power in a three-phase motor such that, on the one hand, a first portion of the rotating field power acts as mechanical drive power for generating the rotary movement of the three-phase rotor of the three-phase motor, and on the other hand, a second portion of the rotating field power acts as electrical supply power for a payload device. Finally, the present disclosure relates to a computer program product that can be loaded directly into a memory of a computing unit of a gantry drive, with program code means for executing such a method when the computer program product is executed in the computing unit.

[0048] With regard to the basic structure of a computer tomography arrangement, a gantry, a gantry drive with a three-phase motor with a three-phase stator and a three-phase rotor, a control unit set up for this purpose and electrical supply power, reference is made to the disclosure of EP 4 285 824 A1. In particular, with regard to the structure of a computer tomography arrangement, reference is made to paragraphs

[0075] to

[0077] , with regard to the structure of a gantry to paragraphs

[0002] to

[0009] , with regard to further aspects of a gantry drive to paragraphs

[0015] to

[0023] , with regard to the structure of a three-phase motor to paragraphs

[0024] to

[0036] , with regard to a compatible control unit to paragraphs

[0037] to

[0055] and with regard to a general method for operating a gantry to paragraphs

[0056] to

[0063] of EP 4 285 824 A1, the disclosure of which is incorporated herein by reference.

[0049] All embodiments described herein can be combined with one another, unless explicitly stated otherwise. The above-described properties, features, and advantages of this disclosure, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of the embodiments, which are explained in more detail in conjunction with the figures.

[0050] The present disclosure is described and explained in more detail below with reference to the exemplary embodiments illustrated in the figures. In the following description of the figures, essentially identical structures and units are generally designated with the same reference numerals as when the respective structure or unit first appeared. Fig. 1 shows a schematic cross-section of a preferred computed tomography device according to an embodiment of the present disclosure; Fig. 2 shows a schematic cross-section of another preferred computed tomography device according to an embodiment of the present disclosure; and Fig. 3 shows a schematic cross section of another preferred computed tomography device according to an embodiment of the present disclosure.

[0051] Fig. 1 shows a schematic cross section of a preferably disclosed computed tomography device with a rotation axis in the z-direction according to an embodiment of the present disclosure. Fig. 1 shows a gantry drive 10, a stationary support ring 20, a rotatable support ring 30, and a tunnel-shaped cavity 40 for accommodating a patient. The stationary support ring 20 is connected to the three-phase stator 50, and the rotatable support ring 30 is arranged in a rotationally fixed manner relative to the three-phase rotor 60. The gantry drive 10 comprises a stationary part and a rotatable part and a load direction (double arrow). The center of gravity of the rotatable support ring 30 is spaced apart in the z-direction from a bearing unit of the stationary support ring 20. The bearing unit comprises a stationary part and a rotatable part. The stationary support ring 20 comprises, for example, a cooling channel 70 from which cooling can be tapped.

[0052] The stationary drive element is arranged further away from the rotation axis of the gantry drive 10 in the radial direction than the rotatable drive element.

[0053] In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs orthogonally (radially) to the rotational axis of the computed tomography device. This arrangement cancels out the reluctance force occurring in the magnetic circuit between the rotating and stationary drive parts. This results in a Fig. 2 and Fig. 3 no additional axial load (z-axis) on the bearing unit.

[0054] Cooling of the rotating and stationary windings is achieved either by convection through a tap into an adjacent cooling channel for air cooling of the rotating system component, or by heat conduction or thermal conduction of the adjacent bearing unit. In this configuration, heat is introduced evenly within the bearing unit, based on comparable losses in the stationary and rotating drive components. The reduction of any preload within the bearing unit due to different material expansions is thus avoided by design.

[0055] In the context of the air gap tolerance, the described embodiment in radial flow arrangement is disadvantageous compared to the axial flow arrangement described below, since in addition to concentricity tolerances, an offset of the running axes of the rotating and stationary system part, for example due to settling behavior, must also be taken into account.

[0056] Another advantage of this design is the small axial distance between the bearing unit and the center of gravity of the rotating system component. This minimizes the torque acting on the bearing unit.

[0057] Fig. 2 shows similar to Fig. 1 shows a schematic cross-section of a preferably disclosed computed tomography device with a rotation axis in the z-direction according to an embodiment of the present disclosure. Correspondences with Fig. 1 will not be repeated.

[0058] The stationary drive element is arranged next to the rotatable drive element in the radial direction of the rotation axis of the gantry drive 10. The stationary bearing element is arranged next to the rotatable drive element in the radial direction of the rotation axis of the gantry drive.

[0059] In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs axially to the rotational axis of the computed tomography device. Due to this arrangement, the reluctance force occurring in the magnetic circuit acts between the rotating and stationary drive parts, compared to the arrangement in Fig. 1 as an additional load for the storage unit.

[0060] Cooling of the rotating and stationary windings is achieved either by convection through a tap into an adjacent cooling channel for air cooling of the rotating system component, or by heat conduction or induction from the adjacent bearing unit. In this configuration, heat input within the bearing unit is almost uniform, based on comparable losses in the stationary and rotating drive components. The loss of any preload within the bearing unit due to different material expansions is thus avoided by design.

[0061] In the context of air gap tolerance, the described embodiment in axial flux arrangement is compared to the one in Fig. 1 described radial flow arrangement has an advantage, since in addition to the existing axial runout tolerances, an offset of the running axes of the rotating and stationary system part, for example due to settling behavior, has no influence.

[0062] An advantage of this embodiment of Fig. 2 is also the design of the bearing unit to minimize its axial distance from the center of gravity of the rotating system component. This minimizes the torque acting on the bearing unit.

[0063] Fig. 3 shows similar to Fig. 1 and Fig. 2 shows a schematic cross-section of a preferably disclosed computed tomography device with a rotation axis in the z-direction according to an embodiment of the present disclosure. Correspondences with Fig. 1 and Fig. 2 will not be repeated.

[0064] The stationary drive element is arranged next to the rotating drive element in the radial direction of the gantry drive's rotation axis. The stationary bearing element is arranged next to the stationary drive element in the radial direction of the gantry drive's rotation axis.

[0065] In this arrangement, the flux axis of the magnetic circuit within the asynchronous machine runs axially to the rotational axis of the computed tomography device. Due to this arrangement, the reluctance force occurring in the magnetic circuit acts between the rotating and stationary drive parts, compared to the arrangement in Fig. 1 as an additional load for the storage unit.

[0066] The cooling of the rotating and stationary windings can be achieved either by convection through a tap into an adjacent cooling channel for air cooling of the rotating system part, or by heat conduction of the adjacent bearing unit. Fig. 1 and Fig. 2, the cooling effect of the rotating assembly is maximized via conduction, as the heat sink and its associated connection are enlarged. A disadvantage of this arrangement is the uneven heat input within the bearing unit due to the component spacing. The loss of any preload within the bearing unit due to varying material expansion must therefore be considered.

[0067] In the context of the air gap tolerance, the described embodiment in axial flow arrangement has an advantage over the radial flow arrangement described above, since in addition to the existing axial runout tolerances, an offset of the running axes of the rotating and stationary system part, for example due to settling behavior, has no influence.

[0068] A disadvantage of this embodiment is the additional Fig. 1 and Fig.2 Increased axial distance of the bearing unit from the center of gravity of the rotating system component. This further increases the torque acting on the bearing unit.

[0069] Although the present disclosure has been illustrated and described in detail by the exemplary preferred embodiments, the present disclosure is not limited by the disclosed examples, and other variations may be derived therefrom by those skilled in the art without departing from the scope of the present disclosure. It should be noted that the terms "comprising" and "having" do not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to the above embodiments may also be used in combination with other features. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] EP 4 285 824 A1 [0002, 0005, 0048]

Claims

[1] Gantry drive (10) for a computer tomography device, - wherein the gantry drive (10) comprises a double-controlled asynchronous machine and a tunnel-shaped cavity (40) for receiving a patient in the computed tomography device along a rotation axis (z) of the gantry drive (10), - wherein the asynchronous machine comprises a three-phase stator (50) and a three-phase rotor (60), wherein the three-phase rotor (60) is arranged in a ring around the rotation axis (z) of the gantry drive (10), wherein the three-phase stator (50) and the three-phase rotor (60) form a three-phase motor for providing a rotating field power, - wherein, by means of the rotating field power, on the one hand, a mechanical drive power for generating a rotary movement of the three-phase rotor (60) relative to the three-phase stator (50) about the rotation axis (z) of the gantry drive (10) can be provided and, on the other hand, an electrical supply power of a payload device can be provided and / or transmitted from the three-phase stator (50) to the three-phase rotor (60). [2] Gantry drive (10) according to claim 1, - wherein the double-controlled asynchronous machine is designed so that the three-phase stator (50) and the three-phase rotor (60) can be controlled. [3] Gantry drive (10) according to claim 1 or 2, - wherein the double-controlled asynchronous machine is designed to provide the mechanical drive power for generating the rotary movement of the three-phase rotor (60) relative to the three-phase stator (50) and the electrical supply power of the payload device. [4] Gantry drive (10) according to one of claims 1 to 3, - wherein the gantry drive (10) is designed without slip rings and / or brushless. [5] Gantry drive (10) according to one of claims 1 to 4, - wherein the gantry drive (10) comprises a stationary drive element, a rotatable drive element, a stationary bearing element and a rotatable bearing element, - wherein the stationary drive element is arranged further away in the radial direction from the rotation axis (z) of the gantry drive (10) than the rotatable drive element. [6] Gantry drive (10) according to one of claims 1 to 4, - wherein the gantry drive (10) comprises a stationary drive element, a rotatable drive element, a stationary bearing element and a rotatable bearing element, - wherein the stationary drive element is arranged in the radial direction from the rotation axis (z) of the gantry drive (10) next to the rotatable drive element, in particular equiradially to the rotatable drive element. [7] Gantry drive (10) according to claim 5 or 6, - wherein the stationary bearing element is arranged in the radial direction from the rotation axis (z) of the gantry drive (10) next to the rotatable drive element and / or next to the stationary drive element, in particular equiradially to the rotatable drive element and / or to the stationary drive element. [8] Computed tomography device comprising a gantry drive (10) according to one of claims 1 to 7, a stationary support ring (20) and a rotatable support ring (30), - wherein the three-phase stator (50) is connected to the stationary support ring (20) in a stationary manner relative to the stationary support ring (20), - wherein the rotatable support ring (30) is arranged at rest on the three-phase rotor (60) relative to the three-phase rotor (60), in particular is arranged such that the rotatable support ring (30) is mounted rotatably relative to the stationary support ring (20) about the rotation axis (z) of the gantry drive (10). [9] Computed tomography device according to claim 8, further comprising the payload device, - wherein the payload device comprises a high-voltage generator, an X-ray source and / or an X-ray detector, - wherein the payload device is arranged on the rotatable support ring (30) in a resting manner relative to the rotatable support ring (30). [10] Use of a gantry drive (10) according to one of claims 1 to 7 for providing a rotating field power in a computer tomography device according to claim 8 or 9 such that, on the one hand, a first portion of the rotating field power acts as mechanical drive power for generating the rotary movement of the three-phase rotor (60) relative to the three-phase stator (50) and, on the other hand, a second portion of the rotating field power acts as electrical supply power of the payload device.

Images