Patent ID: 6819743
Filing Date: 2004-11-16
Classification: A61N,G21K

Abstract:
A multi-leaf collimator apparatus comprising a first leaf plate driving body provided on a first side of the collimator and a second leaf plate driving body provided on a second side of the collimator, the first and second leaf plate driving bodies each including a plurality of movable leaf plates, the plurality of leaf plates of said leaf plate driving body on the first side and the plurality of leaf plates of said leaf plate driving body on the second side being disposed in an opposing relation to form an irradiation field of a radiation beam between the opposing leaf plates, wherein:each of said first and second leaf plate driving bodies comprises a leaf plate moving device for moving said leaf plates by engaging with said plurality of leaf plates and transmitting a driving force to said engaged leaf plates, a driving force transmitting/cutoff device having a first motion moving each of said plurality of leaf plates to positions where each of said leaf plates engages with said leaf plate moving device and a second motion detaching each of said leaf plates from said leaf plate moving device, and a control device for engaging said plurality of leaf plates with said leaf plate moving device by controlling said driving force transmitting/cutoff device and canceling engagements between a leaf plate arrived at a predetermined position in said plurality of leaf plates and said leaf plate moving device by controlling said driving force transmitting/cutoff device.