Computerized tomography system

A drive system for non-mechanically linking the motions of an X-ray source and an X-ray receptor through a predetermined fulcrum point during a tomographic procedure comprising, in combination:

• first and second drive motors respectively coupled to and being operable to simultaneously move said X-ray source and said X-ray receptor in response to respective drive signals applied thereto;
• first circuit means responsive to a first digital control signal to generate and apply drive signals to said drive motor coupled to said X-ray source,
• second circuit means responsive to said second digital control signal to generate and apply drive signals to said drive motor coupled to said X-ray receptor;
• and
• digital control means comprising a stored program digital computer responsive to at least one selected input parameter for a predetermined operating sequence and being operable thereafter to generate said first and second digital control signals having a predetermined mathematical interrelationship based on a selected fulcrum height and the type of tomographic procedure desired, said stored program digital computer being operable in accordance with stored digital instructions and having a memory programmed with successive velocity data values of drive motor operation and additionally including means for periodically accessing said memory to apply said data values in a predetermined sequence to a selected one of said first and second circuit means and additionally including means for scaling said values by computer calculated factors based on said fulcrum point and tomographic procedure desired and to apply said factors selectively to the other of said first and second circuit means.

A drive system for non-mechanically linking the motions of an X-ray source and an X-ray receptor through a predetermined fulcrum point during a tomographic procedure comprising, in combination:

• a first stepper motor coupled to and operable to move said X-ray source, a second stepper motor respectively coupled to and operable to move said X-ray receptor, and a third stepper motor respectively coupled to and being operable to angularly rotate said X-ray source, said first, second and third stepper motors being operable in response to respective pulse signals applied thereto;
• a reference frequency signal source;
• first circuit means coupled to said reference frequency signal source and being responsive to a first digital control signal to generate and apply pulse signals to said first stepper motor coupled to said X-ray source;
• second circuit means coupled to said reference frequency signal source and being responsive to a second digital control signal to generate and apply pulse signals to said second stepper motor coupled to said X-ray receptor;
• third circuit means coupled to said reference frequency signal source and responsive to a third digital control signal to generate and apply pulse signals to said third stepper motor coupled to said X-ray source for providing angular rotation thereof;
• and
• digital control means responsive to at least one selected input parameter for a predetermined operating sequence and being operable thereafter to generate said first, second and third control signals having a predetermined mathematical interrelationship based on a fulcrum height and the type of tomographic procedure desired, said digital control means comprising a stored program digital computer operable in accordance with stored digital instructions and having a memory programmed with successive data values corresponding to the frequency of pulse signals to be applied to at least one of said stepper motors, said pulse signals being derived from said reference frequency signal source, including means for periodically accessing said memory to apply said values to a selected one of said first, second and third circuit means and additionally including means for scaling said values by factors based on said fulcrum point and the tomographic procedure desired and to apply said values thus scaled selectively to the other of said first, second and third circuit means to affect the frequency of the pulse signals applied to the respective stepper motors controlled thereby.

A drive system for non-mechanically linking the motions of an X-ray source and an X-ray receptor through a predetermined fulcrum point during a tomographic procedure comprising in combination:

• first and second drive motors respectively coupled to and being operable to simultaneously move said X-ray source and said X-ray receptor in response to respective first and second pulse trains applied thereto;
• digital control means responsive to at least one selected input parameter for a predetermined operating sequence and being operable thereafter to generate first and second digital control signals having a predetermined mathematical interrelationship based on a selected fulcrum height and the type of tomographic procedure desired;
• a fixed frequency signal source acting as a frequency reference;
• first circuit means coupled to said fixed frequency signal source and being operable in response to said first digital control signal to generate and apply said first pulse train to the stepper motor coupled to said X-ray source;
• second circuit means coupled to said fixed frequency signal source and being operable in response to said second digital control signal to generate and apply said second pulse train to the drive motor coupled to said X-ray receptor;
• said first and second circuit means respectively including first and second programmable frequency divider circuits coupled to said fixed frequency signal source, said first digital control signal being adapted to control the division of the frequency output of said first programmable frequency divider circuit and thereby generate said first pulse train and said second control signal being operable to control the frequency division of the frequency output of said second programmable frequency divider circuit and thereby generate said second pulse train.