Radiation therapy apparatus
A radiation therapy apparatus includes: an annular gantry; an irradiation unit which is provided on the gantry and configured to radiate radiation; a support which supports the gantry; a rotation-driving mechanism which is provided between the gantry and the support and rotates the gantry around a horizontal central axis of the gantry. The rotation-driving mechanism includes: annular rails that are provided on the gantry; and sliding members which are provided on regions of the support that correspond to a lower half of the gantry, slidably guide the rails, and receive at least a load of the gantry in a vertical direction.
1. A radiation therapy apparatus comprising:
an annular gantry;
an irradiation unit which is provided on the gantry and configured to radiate radiation;
a support which supports the gantry;
a rotation-driving mechanism which is provided between the gantry and the support and rotates the gantry around a central axis of the gantry, wherein the rotation-driving mechanism comprises:
annular rails that are provided on the gantry;
first sliding members which are provided on regions of the support that correspond to a lower half at a lower side than a horizontal central axis of the gantry to slidably guide the annular rails and receive at least a load in a vertical direction of the gantry; and
a turning mechanism which supports the support to be turnable about a vertical axis, wherein the turning mechanism comprises:
a base installed on a floor;
turning rails which are provided on one of the base and the support and continue in a circumferential direction centering on the vertical axis;
turning guides which are provided on the other of the base and the support and are slidable along the turning rails; and
an accommodating portion formed in the base, in which at least a portion of the gantry is accommodated between inner circumferential sides of the turning rails.
2. The radiation therapy apparatus according to claim 1 , wherein the rotation-driving mechanism further comprises second sliding members which are provided at positions of the support which are laterally offset with respect to a vertical lower position of the central axis of the gantry to slidably guide the annular rails and restrict displacement of the gantry in a horizontal direction.
3. The radiation therapy apparatus according to claim 2 , wherein the first sliding members and the second sliding members are symmetrically disposed in line with respect to a vertical axis passing through the central axis of the gantry.