Provided is a brushless direct currency (BLDC) motor and a manufacturing method thereof, and more particularly, a brushless direct currency (BLDC) motor including a rotor rotated to drive an impeller and capable of reducing a defective rate of the motor due to a rotational imbalance by controlling a shape of a magnet portion included in the rotor, and a manufacturing method thereof.

A rotor for connection to a stationary member for use in an electric machine is provided. The rotor includes a body defining a center of rotation of the body. The body further defines a first surface extending in a direction generally perpendicular to the center of rotation. The rotor also includes a magnet connected to the body and an adhesive. The adhesive is positioned between the magnet and the body. The adhesive is adapted to assist in securing the magnet to the body. The first surface of the body is adapted to permit removal of material from the body and to assist in balancing the rotor.

A motor includes a rotor having a rotation shaft, a rotor core fixed with respect to the rotation shaft, a magnet attached to the rotor core, and a bearing attached to the rotation shaft. The magnet constitutes a first magnetic pole, and a part of the rotor core constitutes a second magnetic pole. The motor also includes an annular stator surrounding the rotor from outside in a radial direction about a center axis of the rotation shaft, a bearing holding member holding the bearing, and a resin portion covering the stator and the bearing holding member.

The disclosure relates to an electric machine and an assembling method for an electric machine. The electric machine includes: a shaft assembly including a first shaft, a second shaft coaxially disposed within an inner circumference of the first shaft, and a bearing disposed between the first shaft and the second shaft; a first revolving body coaxially connected to the first shaft, wherein the first revolving body includes an annular first adapter bracket, and a tubular structural portion extending in an axial direction is disposed at an inner circumference of the first adapter bracket; a second revolving body coaxially connected to the second shaft and disposed around an outer circumference of the first revolving body; and a guiding assembly disposed between the tubular structural portion and the first shaft to restrict a movement of the first revolving body relative to the first shaft in a circumferential direction and a radial direction.

The disclosure relates to an electric machine and an assembling method for an electric machine. The electric machine includes: a shaft assembly including a first shaft, a second shaft coaxially disposed within an inner circumference of the first shaft, and a bearing disposed between the first shaft and the second shaft; a first revolving body coaxially connected to the first shaft, wherein the first revolving body includes an annular first adapter bracket, and a tubular structural portion extending in an axial direction is disposed at an inner circumference of the first adapter bracket; a second revolving body coaxially connected to the second shaft and disposed around an outer circumference of the first revolving body; and a guiding assembly disposed between the tubular structural portion and the first shaft to restrict a movement of the first revolving body relative to the first shaft in a circumferential direction and a radial direction.

A motor includes an annular core formed by stacking a plurality of electromagnetic steel sheets; end plates disposed at both ends of the core in an axial direction; a balance weight disposed on a side of one of the end plates, the side being opposite the core; and a spacer disposed between the one of the end plates and the balance weight, the spacer being configured to create a space between the one of the end plates and the balance weight. The motor is entirely fastened by allowing at least one of a plurality of rivets arranged in a circumferential direction of the core to pass through the core and the end plates in the axial direction, and allowing remaining at least one rivet to pass through the core, the end plates, the spacer, and the balance weight in the axial direction.

A rotor is provided with injected fixing bars having functional pins formed in a single piece and includes a bar and two or more functional pins. The functional pins include one or more fixing regions for tying of one or more rotor packages of plates of the rotor. A process is for manufacturing the rotor and a rotary electric machine can include the rotor.

A miniature step motor is constructed with a permanent magnet rotor and a hybrid stator assembly. The rotor, mounted for rotation on an axial shaft, has one or more rotor sections or pieces with a pair of magnetic poles on opposed circumferential surfaces of each piece. The stator assembly, with an inner diameter to receive the rotor, is formed from a stack of bipolar phase-stators positioned in different axial planes, each phase-stator interacting with a rotor section via a two-dimensional magnetic flux path that is independent of every other phase-stator in the stack. The at least one rotor section and the phase-stators have different amounts of rotor-stator rotational offsets at specified angles 180°/N relative to each other about the axial shaft, where N is the number of motor phases. The phase-stators can be mutually offset from one another, or the rotor sections can be mutually offset.

An EC motor for an electric hand tool having a stator in which a rotor is rotatably mounted, which comprises a rotor lamination stack, which has a passage opening and is formed of individual laminations, and a rotor shaft which is cast in the passage opening of the rotor lamination stack by means of a casting compound, and having a plurality of permanent magnets, which are received in the pockets formed in the rotor lamination stack. An annular channel, which is connected to the pockets in a fluid-conducting manner via radial channels, each of which is formed of a plurality of channel sections formed in adjacent laminations of the rotor lamination stack, is formed between the rotor shaft and the wall of the passage opening for supplying the casting compound from the annular channel to the pockets. A method is also provided for producing a rotor for an EC motor.

A method for producing an electric motor includes: connecting a first phase coil of three-phase coils to a positive side of a source of electrical power for magnetizing; passing an electric current through the three-phase coils in a state where a center of a magnetic pole of a rotor is rotated a first angle with respect to a center of a magnetic pole of the first phase coil; switching a connection with the positive side of the source of electrical power from the first phase coil to a second phase coil; and passing an electric current through the three-phase coils in a state where the center of the magnetic pole of the rotor is rotated a second angle with respect to a center of a magnetic pole of the second phase coil.