An X-ray tube according to an embodiment of the inventive concept includes a cathode structure; an anode structure spaced vertically from the cathode structure, a gate electrode structure disposed between the cathode structure and the anode structure, an emitter array disposed between the cathode structure and the gate electrode structure, a tube sheath configured to connect the cathode structure and the anode structure, and a fixing unit connected with the gate electrode structure. The cathode structure includes a first rotation shaft and a cathode connected with the first rotation shaft as one body. The gate electrode structure includes a second rotation shaft and a gate electrode connected with the second rotation shaft through a bearing, and the second rotation shaft is connected with the first rotation shaft by a coupling unit. The gate electrode includes a gate electrode substrate and a protruding part that protrudes from the gate electrode substrate toward an emitter. The protruding part of the gate electrode includes a gate hole that vertically overlaps the emitter. The fixing unit includes a ferromagnetic structure attached to one surface of the gate electrode substrate and disposed on an outer portion of the substrate and a permanent magnet disposed adjacent to the ferromagnetic structure with the tube sheath therebetween.

Systems and methods related to hydrodynamic bearings are provided. One example hydrodynamic bearing system includes a sleeve assembly including a cross-member fluidically dividing a first interior cavity from a second interior cavity, a first shaft positioned in the first interior cavity, and a second shaft positioned in the second interior cavity. The hydrodynamic bearing system further includes a first journal bearing including a first fluid interface surrounding at least a portion of the first cantilever shaft and configured to support radial loads and a second journal bearing including a second fluid interface surrounding at least a portion of the second cantilever shaft and configured to support radial loads.

Systems and methods related to hydrodynamic bearings are provided. One example hydrodynamic bearing system includes a sleeve assembly including a cross-member fluidically dividing a first interior cavity from a second interior cavity, a first shaft positioned in the first interior cavity, and a second shaft positioned in the second interior cavity. The hydrodynamic bearing system further includes a first journal bearing including a first fluid interface surrounding at least a portion of the first cantilever shaft and configured to support radial loads and a second journal bearing including a second fluid interface surrounding at least a portion of the second cantilever shaft and configured to support radial loads.

A radiation emission device is provided. The radiation emission device may include a cathode configured to emit an electron beam and an anode configured to rotate on a shaft. The anode may be situated to receive the electron beam from the cathode. The radiation emission device may further include a rotor configured to drive the anode to rotate. The rotor may be mechanically connected to the shaft. The radiation emission device may further include a sleeve configured to support the shaft via at least one bearing. The cathode, the anode, and the rotor may be enclosed in an enclosure that is connected to the sleeve. At least a portion of the sleeve may reside outside the enclosure.

A radiation emission device is provided. The radiation emission device may include a cathode configured to emit an electron beam and an anode configured to rotate on a shaft. The anode may be situated to receive the electron beam from the cathode. The radiation emission device may further include a rotor configured to drive the anode to rotate. The rotor may be mechanically connected to the shaft. The radiation emission device may further include a sleeve configured to support the shaft via at least one bearing. The cathode, the anode, and the rotor may be enclosed in an enclosure that is connected to the sleeve. At least a portion of the sleeve may reside outside the enclosure.

Technology is described for a magnetic lift device for an x-ray tube. In one example, an anode assembly includes an anode, a bearing assembly, a ferromagnetic shaft, and a lift electromagnet. The anode is configured to receive electrons emitted by a cathode. The bearing assembly is configured to stabilize the anode during a rotation of the anode. The ferromagnetic shaft is coupled to the anode and has an axis of rotation that is substantially collinear with an axis of rotation of the anode. The lift electromagnet is configured to apply a magnetic force to the ferromagnetic shaft in a radial direction.

In one embodiment, a rotating anode type X-ray tube comprises a fixed shaft having a first surface, a rotor, a cathode emitting electrons, and an anode target. The rotor comprises a first cylinder having a second surface, a second cylinder, and a third cylinder. A first threaded portion on an inner surface of the first cylinder and a second threaded portion on an outer peripheral surface of the third cylinder are tightened. A screw member is screwed in a third threaded portion on an inner peripheral surface of a hole which penetrates the third cylinder, and a tip portion of the screw member presses the second cylinder against the second surface.

In one example, a lift assembly may exert a force on a rotatable anode of an X-ray source. The lift assembly may include a lift shaft and a lift electromagnet. The lift shaft may be coupled to an anode and configured to rotate around an axis of rotation of the anode. The lift electromagnet may be configured to apply a magnetic force to the lift shaft in a radial direction. The lift electromagnet may include a coupling portion extending between an interior of a vacuum envelope and an exterior of the vacuum envelope and a winding portion coupled to the coupling portion. Windings may at least partially surround the winding portion.

In one example, a lift assembly may exert a force on a rotatable anode of an X-ray tube. The lift assembly may include a lift shaft and a lift electromagnet. The lift shaft may be coupled to the anode and may be configured to rotate around an axis of rotation of the anode. The lift electromagnet may be configured to apply a magnetic force to the lift shaft in a radial direction. The lift electromagnet may include a first pole and a second pole oriented towards the lift shaft. Windings may be positioned around the first pole. The lift assembly may include a heat dissipating structure.

In one example, a lift assembly may exert a force on a rotatable anode of an X-ray source. The lift assembly may include a lift shaft and a lift electromagnet. The lift shaft may be coupled to the anode and configured to rotate around an axis of rotation of the anode. The lift electromagnet may be configured to apply a magnetic force to the lift shaft in a radial direction. The lift electromagnet may include a curved surface that contours around at least a portion of the shaft wall. A radius of curvature of the curved surface of the lift electromagnet may be greater than a radius of curvature of the lift shaft, and the spacing between the curved surface of the lift electromagnet and the shaft wall may be non-uniform.