GENERATOR
An x-ray generator is the device that supplies electric power to the x-ray tube, It is not an electrical generator in the strict sense of the word, because by definition a generator converts mechanical energy into electrical energy. The x-ray generator modifies this energy to meet the needs of the x-ray tube. The tube requires electrical energy to meet the needs of the x-ray tube. The tube requires electrical energy for two purposes: to boil electrons from the filament and to accelerate these electrons from the cathode to the anode. The x-ray generator has a circuit for each of these functions, and we will refer to them as the filament and high-voltage circuits. Also, the generator has a timer mechanism, a third circuit, which regulates the length of the xray exposure.
The mechanism of an x-ray generator is usually continued in two separate compartments: a control panel or console and a transformer assembly. Control panels may be very simple or quite complex, and any attempt to describe a single panel or console would be of little value. The controls allow the operator to select the ap-propriate kVp, rnA, and exposure time for a particular radiographic examination. Meters measure the actual rnA and kVp during the exposure. One exposure button (standby) readies the x-ray tube for exposure by heating the filament and rotating the anode, and the other button starts the exposure. The timing mechanism terminates the exposure
The second component of the x-ray generator, the transformer assembly , is a grounded metal box filled with oil. It contains a low-voltage transformer for the filament circuit and a high-voltage transformer and a group of rectifiers for the high-voltage circuit. The potential differences in these circuits may be as high as 150,000 V, so the transformers and rectifiers are immersed in oil. The oil serves as an insulator and prevents sparking between
the various components. By definition, a transformer is a device that either increases or decreases the voltage in a circuit. A rectifier changes alternating current into direct current
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