A manual of practical X-ray work / by David Arthur and John Muir.

  • Davey Arthur
Date:
1909
Catalogue details

Licence: Public Domain Mark

Credit: A manual of practical X-ray work / by David Arthur and John Muir. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    CHAPTER III INTERMEDIATE APPARATUS Interrupters or Breaks—Induction Coils—Valve Tubes, etc. [Appended to this chapter will be found an explanation of the action of an induction-coil with vibrating break, and instructions for use, which we have by request dealt with in some detail.] For excitation of an X-ray tube, we have seen to be required an electric current of very high potential or electro-motive force. No source other than a static machine directly supplies current of sufficiently high potential; therefore, unless in the case of such machine, a transformer must be interposed between the source and the X-ray tube. For this purpose an induction-coil is ordinarily used. But the current supplied to an induction-coil must be a regularly interrupted current, and to produce such interruption an auxiliary piece of apparatus is usually employed, known as the interrupter or break. These two pieces of apparatus—coil and interrupter—should always be considered jointly, and designed mutually to suit each other. Different breaks produce very different ratfes of interruption, and no single coil can be expected to work efficiently with widely varying rate of interruption. Thus,'a €oil wound to suit a low rate cannot be ' saturated' by each fractional current sent to it by a break giving a much higher rate of interruption ; and, conversely, a coil wound to suit a high rate of interruption cannot respond efficiently to the longer periods of excitation allowed by a more slowly acting break. The duration of each contact, or ' make,' during which current is allowed to pass to the coil is also determined by the
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