Radiation therapy apparatus having retractable beam stopper
AssigneeVarian Associates, Inc.
InventorGeorge L. Coad
Life of this patent
Estimating the term…
Abstract
A translation mechanism for linearly moving a beam stopper in radiation therapy apparatus includes first and second arms pivotally mounted to a support and third and fourth arms pivotally mounted to the first and second arms. The third and fourth arms are attached to the beam stopper and can comprise part of the beam stopper. In one embodiment, the third and fourth arms include disc shaped portions stacked in axial alignment with a drive motor attached to one disc portion ahd having a drive shaft axially aligned with and coupled to the other portion whereby relative rotation of the disc portions effects linear translation of the beam stopper.
Claims20
Radiation therapy apparatus comprising a radiation source, support means for rotating said radiation source about a target area, beam stopper means retractably attached to said support means and positionable to receive radiation passing through the target area, said beam stopper means including first and second arms pivotally attached to said support means, third and fourth arms pivotally attached to said first and second arms, respectively, a beam stopper, means for attaching said third and fourth arms to said beam stopper, and drive means coupled to one of said arms whereby said arms rotate and said beam stopper translates linearly.
Radiation therapy apparatus comprising a radiation source, support means for rotating said radiation source about a target area, beam stopper means retractably attached to said support means and positionable to receive radiation passing through the target area, said beam stopper means including first and second arms pivotally attached to said support means, first and second members, each of said first and second members including a generally disc shaped portion and a peripheral attachment portion, means for rotatably attaching said peripheral attachment portions of said first and second members to said first and second arms, respectively, said disc shaped portions being rotatably stacked in axial alignment, drive means for pivoting said arms and rotating said members whereby said members are translated linearly.
For use with a radiation therapy machine and the like, a retractable beam stopper comprising first and second members, each member including a generally disc shaped portion and a peripheral attachment portion, said disc shaped portions being rotatably stacked in axial alignment, first and second arms, means for pivotally attaching end portions of each of said first and second arms to a peripheral attachment portion of each of said first and second members, respectively, means for pivotally attaching another end of each arm to support means, means mechanically coupling said first and second arms whereby pivoting one arm relative to said support means pivots the other arm relative to said support means, and drive means for pivoting said arms and rotating said disc shaped portions thereby linearly translating said beam stopper.
Dependencies are inferred from the claim text.