摘要:
A brazed X-ray target includes a metallic cap and a graphite back including a nonlinear record groove attached thereto along a stepped surface. An upper corner joint of the stepped surface is distanced from a cap outer edge and a focal track where the maximum heat is generated during use of the target. The graphite back is extended outward toward the cap outer edge to increase a thermal storage of the graphite, and a recess is formed into the cap to maintain a selected moment of inertia of the target and thereby maintain the rotordynamics of a given X-ray tube.
摘要:
A cooling system includes a heat exchanger through which a refrigerant flows, and which rejects heat to a fluid, an evaporator, a first circuit having an expansion device, a second circuit having an expansion machine coupled to a compressor, and a set of valves arranged to direct the refrigerant through the first circuit, the second circuit, or both the first and second circuits based on ambient conditions.
摘要:
A gas turbine engine component is disclosed having a cooling fluid passageway that provides relatively cool fluid to a surface of the gas turbine engine component. The cooling fluid passageway can be shaped in cross section to reduce a stress present in the gas turbine engine component. One form of the shape is non-circular. The gas turbine engine component can be formed such that an overhanging material otherwise formed by the intersection of a cooling fluid passageway and a surface of the gas turbine engine component is absent. The gas turbine engine component can also have a depression formed near the surface of the gas turbine engine component such that the cooling fluid passageway exits into an upstream portion and a downstream portion of the depression.
摘要:
Disclosed is an X-ray detector assembly for use in a computed tomography system. The X-ray detector assembly comprises an array of detector cells coupled between two rails. A thermoelectric cooler is coupled to an end of each of the rails, and is controlled to alternatively heat or cool the detector array to maintain the array in a substantially isothermal and thermally stable condition. The detector assembly preferably includes both passive and active cooling devices and insulation materials for controlling the temperature of the detector assembly. An electrical heater coupled at the center of the detector array can be used in conjunction with the TEC's to control the temperature profile of the detector array, and to minimize changes in the temperature gradients.
摘要:
A thermal energy transfer device for use with an x-ray generating device or x-ray system including an anode assembly having a target, a cathode assembly positioned at a distance from the anode assembly configured to emit electrons that strike the target producing x-rays and residual energy in the form of heat, and a rotatable shaft supported by a bearing assembly. The thermal energy transfer device including a thermal gradient device positioned adjacent to and in thermal communication with one end of the shaft, the thermal gradient device operable for transferring heat away from that end of the shaft, and a fin structure positioned adjacent to and in thermal communication with the thermal gradient device, the fin structure operable for convectively cooling the thermal gradient device.
摘要:
A thermal energy storage and transfer assembly is disclosed for use in electron beam generating devices that generate residual energy. The residual energy comprises radiant thermal energy and kinetic energy of back scattered electrons. The thermal energy storage and transfer assembly absorbs and stores an amount of the residual energy to reduce the heat load on other components in the electron beam generating device. The thermal energy storage and transfer device comprises a body portion of a sufficient thermal capacity to permit the rate of transfer of the amount of the residual energy absorbed into the assembly to substantially exceed the rate of transfer of the amount of the residual energy out of the assembly. The assembly also comprises a heat exchange chamber filled with a circulating fluid that transfers the thermal energy out of the assembly. Additionally, in an x-ray generating device, an x-ray transmissive filter suitable for absorbing residual energy is positioned between the anode and an x-ray transmissive window. The filter reduces the exposure of the window to the residual energy. The filter may additionally comprise a coating layer that further reduces the exposure of the window to the residual energy.
摘要:
X-ray detector apparatus is provided for use in a CT imaging system having a rotatable gantry. The apparatus comprises a selected number of X-ray detector cells and two curved rails, which hold the detector cells in an array comprising an arcuate configuration and mount them onto the gantry for rotation therewith. Conduit segments are distributed along the rails, each conduit segment being proximate to a corresponding group of X-ray detector cells, and a quantity of selected working fluid and a porous wick structure is sealably enclosed in each conduit segment. The fluid is disposed to move along a conduit segment in gaseous form by means of convection, and to move in the opposing direction through the wick structure, in liquid form, by means of capillary action Heat is thereby transferred along a conduit segment to maintain a substantially isothermal condition among the detector cells proximate thereto.
摘要:
A cooling system includes a heat exchanger through which a refrigerant flows, and which rejects heat to a fluid, an evaporator, a first circuit having an expansion device, a second circuit having an expansion machine coupled to a compressor, and a set of valves arranged to direct the refrigerant through the first circuit, the second circuit, or both the first and second circuits based on ambient conditions.
摘要:
A computed tomography system comprises a gantry and an x-ray tube. The gantry rotates about a gantry axis of rotation. The x-ray tube is mounted to the gantry, and comprises a rotatable assembly having a tube axis of rotation. The tube axis of rotation is angularly displaced from the gantry axis of rotation by a tilt angle. Rotation of the x-ray tube about the gantry axis of rotation produces a first moment, and rotation of the rotatable assembly about the tube axis of rotation produces a second moment that opposes the first moment.
摘要:
An x-ray tube and x-ray system including an anode assembly having a shaft with a first end and a second end, a target connected to the first end of the shaft, and a rotor connected to the second end of the shaft. The anode assembly further having spaced-apart bearings rotatably supporting the shaft. The shaft, target, and rotor positioned relative to each other such that the center of gravity of the combination of the shaft, the target, and the rotor is positioned between the bearings. Additionally, the target and rotor may be flexibly interconnected allowing the beneficial use of gyroscopic effects.