Abstract: Provided is a focusing assembly including a focusing barrel and a barrel retaining ring; the focusing barrel includes a first sleeve, a second sleeve, and a third sleeve that are sequentially sleeved from inside to outside of the focusing barrel; the first sleeve is provided with a lens mounting portion for mounting a focusing lens, a first end of the second sleeve is provided with a display screen mounting portion for mounting a display screen, a second end of the second sleeve is detachably connected to the barrel retaining ring, the first end and the second end being opposite ends of the second sleeve; and the lens mounting portion and the display screen mounting portion are configured such that the relative position thereof in a focusing direction of the focusing assembly is adjustable.

Abstract: A brushless direct current motor and a dual clutch transmission employing the motor are provided. The motor includes a stator including stator core and a winding wound around the stator core, and a rotor rotatable relative to the stator. The rotor includes a shaft, a rotor core fixed to the shaft, and a plurality of permanent magnets. The rotor core is fixed to the shaft and includes a plurality of accommodations arranged along a circumferential direction of the rotor. Each of the accommodations substantially extends along a radial direction and an axial direction of the rotor. The permanent magnets are respectively arranged at corresponding accommodations. A relationship of an axial length Lr of the rotor core, an axial length Lm of each of the permanent magnets, and an axial length Ls of the stator core is Lm>Lr?Ls.

Abstract: A brushless direct current motor and a dual clutch transmission employing the motor are provided. The motor includes a stator including stator core and a winding wound around the stator core, and a rotor rotatable relative to the stator. The rotor includes a shaft, a rotor core fixed to the shaft, and a plurality of permanent magnets. The rotor core is fixed to the shaft and includes a plurality of accommodations arranged along a circumferential direction of the rotor. Each of the accommodations substantially extends along a radial direction and an axial direction of the rotor. The permanent magnets are respectively arranged at corresponding accommodations. A relationship of an axial length Lr of the rotor core, an axial length Lm of each of the permanent magnets, and an axial length Ls of the stator core is Lm>Lr?Ls.