A motor and a rotating shaft cooling device thereof are disclosed. A rotating shaft of the motor is formed with an annular space. A shaft has a front end and a rear end. The shaft is a blind tube formed with a channel communicating with the annular space through a plurality of nozzles. The distance between the nozzles and the rear end is less than one-half of the length of the shaft. A cooling fluid flows through the nozzles to form a jet array to impinge on the inner wall of the rotating shaft to cool the rotating shaft, and flows back in the annular space to enhance the cooling effect, increase the heat exchange area, and improve the cooling effectiveness of the rotating shaft.

A motor and a rotating shaft cooling device thereof are disclosed. A rotating shaft of the motor is formed with an annular space. A shaft has a front end and a rear end. The shaft is a blind tube formed with a channel communicating with the annular space through a plurality of nozzles. The distance between the nozzles and the rear end is less than one-half of the length of the shaft. A cooling fluid flows through the nozzles to form a jet array to impinge on the inner wall of the rotating shaft to cool the rotating shaft, and flows back in the annular space to enhance the cooling effect, increase the heat exchange area, and improve the cooling effectiveness of the rotating shaft.

A structure for sealing an electric motor so that it is not affected by the humidity from the environment it is placed in, while at the same time the heat generated within the structure is removed into the environment preventing long term motor damage.

A structure for sealing an electric motor so that it is not affected by the humidity from the environment it is placed in, while at the same time the heat generated within the structure is removed into the environment preventing long term motor damage.

An electric hydrofoil board having a submersion-cooled powertrain is provided. A powertrain assembly, which includes a motor housed in a motor assembly and an electronic speed controller housed in a nose cone assembly that is fastened to the motor assembly, is attached to a lower end of a mast of the hydrofoil board so that the powertrain assembly remains submerged at all times during normal use of the hydrofoil board in a body of water. The flow of water around the powertrain assembly during normal use cools heat-generating components of the electronic speed controller and motor.

An electric hydrofoil board having a submersion-cooled powertrain is provided. A powertrain assembly, which includes a motor housed in a motor assembly and an electronic speed controller housed in a nose cone assembly that is fastened to the motor assembly, is attached to a lower end of a mast of the hydrofoil board so that the powertrain assembly remains submerged at all times during normal use of the hydrofoil board in a body of water. The flow of water around the powertrain assembly during normal use cools heat-generating components of the electronic speed controller and motor.

A motor includes a rotor that is rotatable about a central axis and a stator that radially opposes the rotor with a gap interposed therebetween. The stator includes a stator core that includes an annular core back surrounding the central axis and a tooth extending to a radially inner side from the core back, and a coil that is wound around the tooth. The stator core includes at least one hole penetrating in an axial direction of the central axis, and a slit including a space connecting the hole and a radially outer side of the stator core. A heat pipe is held in the hole and extends in an axial direction along the hole, and an adhesive is between the hole and the heat pipe.

A motor includes a rotor that is rotatable about a central axis and a stator that radially opposes the rotor with a gap interposed therebetween. The stator includes a stator core that includes an annular core back surrounding the central axis and a tooth extending to a radially inner side from the core back, and a coil that is wound around the tooth. The stator core includes at least one hole penetrating in an axial direction of the central axis, and a slit including a space connecting the hole and a radially outer side of the stator core. A heat pipe is held in the hole and extends in an axial direction along the hole, and an adhesive is between the hole and the heat pipe.

A planar member for a stator stack comprises a stator yoke defining a central longitudinal axis, a first surface facing radially outward, and a second surface facing radially inward, a tooth extending radially inwards from the second surface, a first tooth tip extending circumferentially from a radially inward end of the tooth, a second tooth tip extending circumferentially from the radially inward end of the tooth, a first slot portion defined between the first tooth tip and the second surface, a second slot portion defined between the second tooth tip and the second surface, and a slot cooling fin extending radially from the stator yoke into the first slot portion.

A planar member for a stator stack comprises a stator yoke defining a central longitudinal axis, a first surface facing radially outward, and a second surface facing radially inward, a tooth extending radially inwards from the second surface, a first tooth tip extending circumferentially from a radially inward end of the tooth, a second tooth tip extending circumferentially from the radially inward end of the tooth, a first slot portion defined between the first tooth tip and the second surface, a second slot portion defined between the second tooth tip and the second surface, and a slot cooling fin extending radially from the stator yoke into the first slot portion.