An irradiation apparatus attached to a rotary gantry includes a middle housing unit and a lower housing unit. Touch sensor apparatuses are attached to a middle housing unit, and touch sensor apparatuses are attached to a lower housing unit. The touch sensor apparatus includes a cover, a pair of cover support apparatuses for attaching the cover to a support member of the middle housing unit, and a sensor unit attached to each cover support apparatus. When the cover comes into contact with a bed and moves toward the support member during rotation of the irradiation apparatus, a link such as a cover support apparatus activates the sensor unit, and a contact signal is output. The touch sensor apparatuses also function in the same manner.