Medical image diagnostic apparatus

1. A medical image diagnostic apparatus comprising:

a gantry having a bore along a vertical direction;

a plurality of columns that movably support the gantry along the vertical direction, with one end of the bore facing a floor surface and the gantry being interposed between the plurality of columns;

a plurality of gantry drive motors that move the gantry along the vertical direction;

a plurality of position detectors that detect a plurality of support positions at which the gantry is supported in each of the plurality of columns; and

gantry control circuitry that determines whether or not movement of the gantry along the vertical direction is possible, based on information regarding misalignment between the plurality of support positions.

2. The medical image diagnostic apparatus according to claim 1 , wherein

the gantry control circuitry determines the movement is impractical when the misalignment information between the plurality of support positions in the vertical direction exceeds a threshold, and

the gantry drive motors stop the movement in response to a determination that the movement is impractical.

3. The medical image diagnostic apparatus according to claim 2 , wherein

the gantry drive motors interlock the gantry after stopping the movement so that the gantry is not moved.

4. The medical image diagnostic apparatus according to claim 2 , further comprising a display for notifying an operator of a warning regarding the misalignment information in response to the determination that the movement is impractical.

5. The medical image diagnostic apparatus according to claim 3 , further comprising

a gantry input interface that is provided on at least one of the plurality of columns, that accepts a release instruction to release an interlock of the gantry in a state where the gantry is interlocked, and that accepts a movement instruction to move the gantry, wherein

the gantry drive motors ascend the gantry in accordance with the movement instruction that is input after the release instruction.

6. The medical image diagnostic apparatus according to claim 2 , wherein

the gantry control circuitry determines whether or not the misalignment information is included in a range that is defined by the threshold and a small threshold smaller than the threshold, and

the gantry drive motors change a moving speed of the plurality of support positions so as to eliminate the misalignment information and moves the gantry, if it is determined that the misalignment information is included in the range and imaging for a subject is not in progress.

7. The medical image diagnostic apparatus according to claim 6 , further comprising a memory that stores, when it is determined that the misalignment information is included in the range, position misalignment information including the misalignment information and a point in time when the misalignment information occurs.

8. The medical image diagnostic apparatus according to claim 1 , wherein

the position detectors

are a plurality of encoders located in the plurality of columns, and/or a plurality of gantry detection sensors that are located at a position included in one horizontal plane in the plurality of columns and that detect whether or not part of the gantry arrives at a detection region in the horizontal plane,

output, if the position detectors are the plurality of encoders, encoder values to the gantry control circuitry as information related to the plurality of support positions, and

output, if the position detectors are the plurality of gantry detection sensors, timing of detecting part of the gantry to the gantry control circuitry as information related to the plurality of support positions.

9. A medical image diagnostic apparatus, comprising:

a gantry having a bore along a vertical direction;

a plurality of columns that movably support the gantry along the vertical direction, with one end of the bore facing a floor surface and the gantry being interposed between the plurality of columns;

a plurality of gantry drive motors that move the gantry along the vertical direction;

a plurality of load detectors that respectively detect a plurality of loads related to movement of the gantry in the gantry drive motor; and

gantry control circuitry that determines whether or not movement of the gantry along the vertical direction is possible based on load information regarding the plurality of loads.