CT scanner

Claim 1

A CT scanner for producing transverse layer images of a patient comprising: a rotating frame having a hole which permits insertion of the patient, and which can rotate around the patient; a stationary base for supporting the rotating frame; a radiation source mounted on said rotating frame for exposing fan-shaped radiation beams on the patient; a radiation detector set on the rotating frame for detecting the fan-shaped radiation beams permeating the patient; a power source securely set at the sationary base for generating a first voltage power; a high voltage generator built on the rotating frame for transforming a first voltage power to a second voltage power larger than the first voltage power and for impressing the second voltage power on the radiation source; a cable member for conducting the first voltage power from the power source to the high voltage generator; and a cable-handling device for handling the cable member to permit the rotation of the rotating frame, the cable-handling device comprising a ring-shaped housing having an outer peripheral member and an inner peripheral member for holding the cable member wound between the outer peripheral member and the inner peripheral member, either of which is disposed on and rotatable with the rotating frame and the other of which is fixed at the stationery base; the cable-handling device also comprising a plurality of rollers each having a rotating shaft and being arranged in the housing in its circumferential direction, with the axis of the roller aligned with that of the housing, the cable member being wound around the inner peripheral member of the ring-shaped housing at least once in a first direction, wound about half the periphery of a prescribed one of the rollers, and wound at least once around the outside of the rollers in a second direction opposite to the first direction, and the end portions of the cable member facing the outer and inner peripheral members being fixed thereto; the cable-handling device further comprising a ring-shaped coupling member extending about the inner peripheral member of the ring-shaped housing, which is in engagement with the shafts of the rollers to position the rollers in the housing so as to surround the inner peripheral member, the ring-shaped coupling member being freely movable relative to the outer and inner peripheral members, and an auxiliary roller having a rotating shaft, arranged in the housing with the axis of the auxiliary roller aligned with that of the housing, and engaged with the ring-shaped coupling member, the auxiliary roller defining the locus of the cable member between the auxiliary roller and the prescribed one of the rollers.