Abstract: A stator, a motor, and an electric vehicle are provided. The stator includes: a housing, where the housing has an accommodation space, and an oil inlet is disposed on the housing; a ring-shaped iron core punching sheet, where the iron core punching sheet is disposed in the accommodation space, and abuts against an inner wall of the housing; a spacer sleeve, where the spacer sleeve is sleeved in the iron core punching sheet, an outer surface of the spacer sleeve abuts against a side that is of the tooth part and that faces away from the yoke part, and a slot opening of the stator slot fits with the spacer sleeve to form a third cooling channel; and a flow guiding assembly, where the flow guiding assembly is disposed in the accommodation space. The three-layer oil-injection cooling design can improve a heat dissipation capability of the stator.

Abstract: A braking mode switching apparatus includes a braking mode selection component, a transmission member, a stopper, a driver, and a motion control component. The braking mode selection component can move between a first position corresponding to a first braking mode and a second position corresponding to a second braking mode. The transmission member has a first transmission portion and a second transmission portion. The stopper includes a first stopper portion and a second stopper portion. The motion control component is configured to abut against the first stopper portion in response to a case in which the driver is powered on, where the braking mode selection component is located in the first position; and abut against the second stopper portion in response to a case in which the driver is not powered on, where the braking mode selection component is located in the second position.

Abstract: A parking mechanism that includes a wheel disc, a wedge disc, and a drive assembly. An axis of the wheel disc and an axis of the wedge disc both are aligned with an axis of a motor shaft. A wedge groove with an opening facing the wheel disc is formed on a surface of the wedge disc facing the wheel disc, and a movable part in contact with the wheel disc is disposed in the wedge groove. In a direction from a bottom of the wedge groove to the wheel disc, a groove depth at a first end of the wedge groove is greater than a size of the movable part, and a groove depth at a second end of the wedge groove is less than the size of the movable part. The parking mechanism can provide stepless variable parking force.

Abstract: An electronic mechanical brake system and a vehicle. The electronic mechanical brake system includes a brake pedal, an electronic brake mechanism, a mechanical brake mechanism, a brake, and a switch mechanism with a first state and a second state. The electronic brake mechanism includes a controller and an electronic signal sensor. The controller, the electronic signal sensor, and the brake are electrically connected. When the switch mechanism is in the first state, the electronic signal sensor is configured to receive a braking signal of the brake pedal and transmit the braking signal to the controller. The controller controls the brake to brake based on the braking signal. The electronic mechanical brake system can improve driving safety. In addition, reliability of the mechanical brake system is high, and costs are low.

Abstract: A ring light source system for an interferometer with adjustable ring radius and ring radial width may comprise a laser light source, an expander and collimator optical system, an adjustable aperture, a binary phase grating, a variable-focus optical system, and a spatial filter. The expander and collimator optical system is configured to convert a light beam from the light source into a parallel light beam. The adjustable aperture is configured to adjust a diameter of the parallel light beam. The light beam with the diameter adjusted by the adjustable aperture is incident perpendicularly onto the binary phase grating, followed by the variable-focus optical system. The filter is positioned on a back focal plane of the variable-focus optical system, and is configured to receive a ring light source. The ring radius and radial width of the light source are adjustable by adjusting a focus length f1 of the variable-focus optical system.

Abstract: A ring light source system for an interferometer with adjustable ring radius and ring radial width may comprise a laser light source, an expander and collimator optical system, an adjustable aperture, a binary phase grating, a variable-focus optical system, and a spatial filter. The expander and collimator optical system is configured to convert a light beam from the light source into a parallel light beam. The adjustable aperture is configured to adjust a diameter of the parallel light beam. The light beam with the diameter adjusted by the adjustable aperture is incident perpendicularly onto the binary phase grating, followed by the variable-focus optical system. The filter is positioned on a back focal plane of the variable-focus optical system, and is configured to receive a ring light source. The ring radius and radial width of the light source are adjustable by adjusting a focus length f1 of the variable-focus optical system.