| 摘要 |
PURPOSE:To obtain an X-ray-tube-current controlling device which can perform the controlling easily with a high stability and has a sufficient safety function by adopting an inverter-type heating system, and performing the controlling according to the indication of the control processor of an inverter. CONSTITUTION:In performing monitoring to prevent any excessively large current from flowing in an X-ray tube filament, an abnormality-indicating signal (d) is generated in order to prevent any excessively large current from flowing out during the detection of abnormality, thereafter being incorporated into an inverter circuit 8. For instance, during the detection of abnormality, a command signal is produced wherein the current of which can preheat the X-ray tube filament. A signal (c) corresponding to the actual current of the X-ray tube works as a feedback signal. The inverter circuit 8 performs feedback control so that the signal (c) coincides with a signal (b) by comparing their magnitudes. In addition, at the time of the generation of abnormality, it causes the preheating current to flow in the filament of an X-ray tube 10. The output of the inverter circuit 8 causes a filament current to be set through a transformer 94 thereby causing a given current to flow in the filament. |
