Abstract: A spot filmer for a diagnostic X-ray apparatus can be front or back loaded with two standard sizes of X-ray film cassettes. This versatility is achieved by the provision of a pair of cassette holding half trays or frames and a precision drive including stepper motors enabling the cassette frames to be driven in unison longitudinally and transversely and in opposite directions transversely to adjust for cassette sizes and to achieve firm holding of cassettes during transport and radiography. Mechanical stops are not required in the precision drive. A cassette back edge locator bar is connected by a parallel bar linkage to each cassette half tray or frame and the locator bar is advanced and retracted automatically in response to relative lateral movements of the frames by the precision drive. Compactness, strength and durability and high reliability of the mechanism are attained. The precision drive is compatible with computer controls.

Abstract: A tomographic system wherein a movable overhead support containing a tiltable X-ray source is non-mechanically coupled to an X-ray receptor beneath an examination table for effecting a desired type of tomographic sweep or scan under the direct control of a stored program microcomputer. Depending upon the parameters inputted to the computer by the operator, the computer enables self-centering control circuits for the source and receptor whereby they are independently brought into vertical alignment over the examination table and thereafter caused to move in opposite directions under precise control of synchronized and mathematically related pulse trains applied to respective stepper motors, first to a calculated reference position and then in predetermined mutual relationship to obtain a tomogram.

Abstract: A diagnostic X-ray system operative in response to control signals from a stored program digital computer to generate an X-ray beam and to produce an image of the object through which the X-ray beam passes. The computer which is preferably a microprocessor has a plurality of selectable programs stored in a digital memory and is operable to control a plurality of operations such as maximizing image quality in terms of resolution, verifying the available anode heat capacity, providing the necessary wait time between successive exposures in a tomographic series, storing the X-ray tube(s) histories, storing and recalling X-ray factors on an anatomic basis and, among other things, making a calculation and display of a pseudo-dose.

Abstract: A motorized device for rotating i.e. tilting the X-ray tube assembly in a linear and/or complex tomography radiographic system comprising the combination of a permanent magnet stepper motor coupled to a rotatable X-ray tube assembly through a helicon gear set and a spur gear set. The X-ray tube assembly incrementally rotates one angular step with each input drive pulse applied to the stepper motor from a pulse generator operated in accordance with a control input applied from an electronic control system in response to sensed positional change of the X-ray tube assembly. The stepper motor when unenergized is nevertheless adapted to provide a holding torque capability which eliminates the need for a separate brake assembly.

Abstract: A system for conducting circular as well as complex tomographic procedures utilizing apparatus which has no mechanical linkage between the X-ray source and the X-ray receptor. The path of travel of the X-ray source both circularly and linearly is sensed by electromagnetic radiation and more particularly by light radiation which is generated by a laser. The linear travel is sensed by means of reflected laser radiation directed to the X-ray source and fed to an interferometer. The circular travel, on the other hand, is sensed by means of a laser gyroscope also receiving light radiation from a laser. Optical energy sensing means is thus used to generate command signals which are coupled to respective drive motors which act to rotate and when desirable, translate the X-ray receptor so that its motion follows the motion, both orbital and linear, of the X-ray source for performing any desired type of tomographic procedure.

Abstract: A bucky translated under an X-ray table in radiographic apparatus of the linear tomography type wherein precise positioning with respect to the X-ray tubestand is achieved by a combination of a ball screw drive attached to the bucky and a permanent magnet stepper motor coupled thereto which incrementally rotates one step with each input drive pulse applied thereto from a pulse generator operated in accordance with a control input applied from an electronic control system in response to the sensed position change of the tubestand.

Abstract: A linear tomographic method and apparatus wherein an overhead tube-stand or X-ray tube unit is non-mechanically coupled to a bucky or X-ray film holder to produce linear tomographs. No physical attachment exists between the tube-stand and the bucky. The tube-stand position is sensed by electro-magnetic radiation and more particularly by light radiation which is generated by a laser and directed to a reflector attached to the tube-stand adjacent to the tube focal spot. Light energy is reflected therefrom and sensed by an interferometer which produces a tube-stand position signal which is used to generate a command signal to operate respective drive motors which translate the bucky in an opposite direction to the tube-stand and simultaneously rotate the X-ray tube so that the X-ray focal spot, center of film, and imaginary fulcrum point remain substantially colinear during a tomographic sweep.

Abstract: An eight bit binary address signal is generated in response to a selected time station, X-ray tube, focal spot and anode rotation speed which is then used to address a read only memory (ROM) pre-programmed with specific binary representations of exact values on the manufacturer's high set rating chart curves which represents the maximum power allowed for each selected type of X-ray exposure desired. Once the exposure parameters are selected, the read only memory outputs a unique binary digital signal which is fed into a digital to analog converter which in turn generates an equivalent analog voltage. This analog voltage of maximum allowable power is then compared against the power (kV .times. mA) selected to inhibit further operation if an unsafe condition exists or thereafter cause a proper adjustment to occur while permitting an X-ray exposure for a safe condition, thus allowing the radiologist to utilize the X-ray tube to its fullest capability.

Abstract: To overcome floor clearance problems, a tiltable X-ray table is tilted at an accelerated rate between level and upright positions by a variable ratio positive gear drive. Simultaneously the table is caused to translate at a constant or linear rate by primary drive means mounted directly on the movable table body or chassis. Thus, the ratio of table body translation to tilt is greater at the beginning of table body travel than at later stages of travel. Table body translation is effected by twin ball nut screw shaft assemblies carried by opposite sides of the table body or chassis.

Abstract: A shutter phase lock circuit for a pair of biplane cinecameras having multiframe speeds utilized in a diagnostic X-ray system wherein the cameras are driven by polarized synchronous motors. Each of the cameras have a rotating shutter which is mechanically coupled to a commutator which has a 50% duty cycle and produces a square wave output pulse. The pulses are compared provided that the same camera speed has been selected for both cameras and in the event that two pulses are out of phase by a predetermined phase angle taking into account compensation for mechanical errors, causes an error signal pulse to be produced whose pulse width is a function of the camera speed selected.

Abstract: An X-ray tube protective circuit wherein the selected exposure time and X-ray tube power are compared prior to operation to determine whether or not a condition exists which would exceed the anode rating of the tube and thereafter prevents operation while permitting an X-ray exposure for a safe condition. The subject invention is directed to a means for reducing the number of switch decks normally required in connection with a plurality of resistive voltage divider networks utilized to simulate the tube rating charts for the X-ray tube(s) utilized and comprises a plurality of resistive networks simulating rating chart curves mounted on a plug-in printed circuit board and coupled to a common time select switch deck by means of an isolating diode network.

Abstract: In an X-ray collimator including both "near" and "far" shutter mechanisms, the improvement comprising locating two pairs of independently movable near shutters within an outwardly extending lead cone. The cone is positioned against the X-ray generator tube window and as a result the near shutters are in closer proximity to the focal spot of a rotating anode disc of an X-ray tube than heretofore possible. The cone contains an aperture which defines the maximum size of the primary beam passing through the shutter mechanisms; however, the body of the cone and the closer positioning of the near shutters to the focal spot effectively controls and restricts secondary radiation which is emitted at angles different from the primary beam passing through the collimator.