Abstract: An automatic positioning device for helical tomotherapy plan verification is provided. The device includes a base located on a treatment bed of helical tomotherapy equipment, a lifting platform fixedly connected to a top of the base, a three-dimensional verification phantom fixedly connected to other ends of the two support rods, and an early warning component. A bearing platform is fixedly connected to a top of the lifting platform, a moving platform is arranged on the bearing platform, and ends of two support rods are fixedly connected to a side, close to the treatment bed, of the moving platform. The three-dimensional verification phantom extends into a treatment aperture through the moving platform. The early warning component includes two early warning pieces respectively arranged on the two support rods.

Abstract: Disclosed is a large-current and low-voltage servo motor, which includes: a housing with a mounting space inside; a stator assembly including a stator core arranged in the mounting space, and an inner circumference of the stator core being provided with stator slots for receiving coils, a coil winding being received in the stator slots, and the coil winding being a three-phase coil winding; and a rotor assembly including a rotor core, the stator core being sleeved on an outer peripheral surface of the rotor core, a plurality of magnetic steels of an arc shape being adsorbed on an outer peripheral surface of the rotor core, each magnetic steel having an inner arc surface and an outer arc surface eccentrical to the inner arc surface, and the plurality of magnetic steels are sequentially distributed to form alternate N and S polarities.