Proposed is an air gap adjustment apparatus. The apparatus is for enabling an air gap between the inner surface of a stator and the outer surface of a rotor, which are installed in an inner space of a housing, to be uniform overall. A plurality of fastening holes are formed so as to surround a shaft through hole of an end plate constituting the housing. A fastener, which has passed through a bearing housing of a bearing, is fastened to each fastening hole so as to mount the bearing to the end plate. An adjusting member body of an adjusting member, which has passed through the bearing housing, is positioned in an adjusting member seating part which is formed at the entrance of each fastening hole. The adjusting member rotates about the adjusting member body so that a head part may adjust the position of the bearing.

The present invention provides a handheld electric tool and a motor assembly for a handheld electric tool. The handheld electric tool of the present invention comprises a housing, a working member, a motor and a motor support. The motor support comprises a first part positioned at a far-side end of the motor and fixedly connected to the housing, and a second part extending from the first part into the interior of the motor and fixedly connected to a stator of the motor. The second part is provided with a first through-hole for a rotor shaft of the motor to pass through, and an output end of the rotor shaft extends through the first through-hole and drives the working member to move. The handheld electric tool provided in the present invention can prevent excessive transmission of motor vibration to the housing, and can pump fluid through the motor to cool components in the housing. Furthermore, the motor assembly of the present invention has an ingenious layout, making the machine as a whole smaller and more lightweight.

A rotor includes a shaft extending in an axial direction, a cylindrical magnet portion provided at an outer peripheral portion of the shaft, a cylindrical scattering-prevention member provided so as to cover an outer peripheral surface of the magnet portion, a first balancing member provided at one end of the magnet portion in the axial direction, and a second balancing member provided at the other end of the magnet portion in the axial direction from which one end side of the shaft extends in the axial direction and having a diameter smaller than the inner diameter of the scattering-prevention member and the second balancing member has an end surface in contact with the magnet portion, the end surface being not surrounded by the scattering-prevention member.

A brushless motor includes a stator assembly and a rotor assembly one coaxially disposed around the other. The rotor assembly includes a spindle and a rotor yoke coaxially disposed around the spindle. At least two magnet receiving grooves for receiving magnets are formed in an inner wall of the rotor yoke in a circumferential direction, the magnets are inserted into the magnet receiving grooves, and a magnetism isolating gap is formed between the at least two magnet receiving grooves. Through the external-rotor design, the size and weight of the motor are effectively reduced, the working efficiency of the motor is effectively improved under the same power, the life of a lithium battery is further prolonged, the energy conversion requirement is met, and user experience is improved.

A miniature handheld electric traction device including a shell, a power supply part, a power motor, a reduction gear set, a braking part and a winding drum, wherein the power motor, the reduction gear set and the winding drum are arranged in the shell; the power motor is linked with the winding drum through the reduction gear set; a surface of the winding drum is wound with a traction rope; the reduction gear set includes a planetary gear; the sun gear of the planetary gear is coaxial with the winding drum; the power motor or the motor shaft of the power motor is inserted into the inner ring of the winding drum; the motor shaft is linked with the planetary gear.

A high-efficiency, high specific power electric motor/generator for aircraft use provides a cantilevered external rotor removed from load thrust. and vibration by an isolator and hearing set between the rotor and stator reducing material demands and weight otherwise required for stiffness to preserve close rotor/stator proximity.

An electric motor includes: a rotor including a first rotor core and a second rotor core; and a stator. A minimum distance from the first rotor core to the stator is shorter than a minimum distance from the second rotor core to the stator. A maximum radius of the first rotor core is longer than a maximum radius of the second rotor core. A shape of a first thin-wall part of the first rotor core and a shape of a second thin-wall part of the second rotor core are the same.

Provided is an axial gap type motor employing a non-rare earth magnet, and a water pump using same. The axial gap type motor for a water pump (EWP) comprises: a rotor rotatably supported on a fluid flow passage between a pump cover and a body case; a stator arranged in a lower space formed by the body case and an upper cover, so as to generate a rotating magnetic field, thereby rotating the rotor; and a partition arranged on the body case in order to separate the rotor from the stator. The rotor can use a ferrite magnet, which is a non-rare earth magnet.

The motor includes a shaft, a cartridge including a plurality of bearings that support the shaft, and a sleeve that surrounds the bearings, and a housing including a bottom portion for receiving an impact from outside and an attaching portion provided in the bottom portion. The bottom portion of the housing extends in a direction intersecting with respect to a longitudinal direction of the shaft, and the cartridge is removably attached to the attaching portion.

A rotor bearing assembly for an underwater generator of a fluid flow power plant includes a hollow cylindrical bearing carrier configured to be inserted into an interior of a rotor and releasably connected to the rotor such that they rotate together and an axle journal extending into an interior of the bearing carrier and rotatably supporting the bearing carrier. The bearing the axle journal and the bearing carrier are configured as an installation unit such that a portion of the bearing carrier is insertable into the rotor interior and removable from the rotor interior while attached to the axle journal. Also a generator including the rotor bearing assembly.