X-ray diagnostic apparatus with an automatic exposure timer

Claim 1

An X-ray diagnostic installation comprising an X-ray tube housing having an X-ray tube mounted therewithin, an X-ray film cassette drawer disposed in spaced relation to said X-ray tube housing for receiving and holding a planar X-ray film cassette, a diaphragm housing disposed between said X-ray tube housing and said film cassette drawer and containing a primary X-ray focusing diaphragm and a light visor for illuminating a region of the body of a patient overlying said cassette drawer, an X-ray generator comprising an automatic X-ray exposure timer having a measuring probe adjustably positionable within said cassette drawer in parallel relation to the plane of the X-ray film cassette received therewithin, means operatively interconnecting said X-ray tube and said X-ray generator, said X-ray tube housing, said cassette drawer and said diaphragm housing being arranged in aligned relation with one another, shadow producing means adjustably positionable on said diaphragm housing in operative association with said light visor for producing an optically visual measuring area of selectively adjustable size and location on the body of the patient overlying said cassette drawer, first position determining means on said diaphragm housing for determining the position of said shadow producing means relative to said diaphragm housing, and second position determining means on said cassette drawer and on said measuring probe corresponding to said first position determining means for determining the position of said measuring probe relative to said cassette drawer and for positioning said measuring probe in alignment with the measuring area produced by said shadow producing means.