A reciprocating tool includes a motor, a reciprocating member, and a crank mechanism. The motor is disposed in a housing. The reciprocating member projects from the housing. The crank mechanism converts rotation of a rotation shaft of the motor into reciprocation of the reciprocating member. The crank mechanism rotates around an axis in a lateral direction by rotation transmission from the rotation shaft, and the crank mechanism includes a crank member having an eccentric pin, a connecting rod coupling the eccentric pin to the reciprocating member, and a balancer coupled to the eccentric pin, and the balancer is supported by the eccentric pin alone in the housing.

A reciprocating tool includes a motor, a reciprocating member, and a crank mechanism. The motor is disposed in a housing. The reciprocating member projects from the housing. The crank mechanism converts rotation of a rotation shaft of the motor into reciprocation of the reciprocating member. The crank mechanism rotates around an axis in a lateral direction by rotation transmission from the rotation shaft, and the crank mechanism includes a crank member having an eccentric pin, a connecting rod coupling the eccentric pin to the reciprocating member, and a balancer coupled to the eccentric pin, and the balancer is supported by the eccentric pin alone in the housing.

An oscillating power tool with an electric motor is provided, including an armature shaft with an armature and a fan wheel, including an eccentric arranged on the armature shaft at one end thereof, a first balancing mass for balancing an unbalance of the eccentric and possibly an eccentric bearing, being arranged in the proximity of the eccentric or the eccentric bearing, respectively, however, at an axial distance, further including a second balancing mass for balancing a couple unbalance caused by the axial distance between the eccentric and the eccentric bearing, respectively, and the first balancing weight, wherein the second balancing mass is arranged on the armature shaft at the side facing away from the eccentric or the eccentric bearing. Also a method for balancing such an electric motor is provided.

An oscillating power tool with an electric motor is provided, including an armature shaft with an armature and a fan wheel, including an eccentric arranged on the armature shaft at one end thereof, a first balancing mass for balancing an unbalance of the eccentric and possibly an eccentric bearing, being arranged in the proximity of the eccentric or the eccentric bearing, respectively, however, at an axial distance, further including a second balancing mass for balancing a couple unbalance caused by the axial distance between the eccentric and the eccentric bearing, respectively, and the first balancing weight, wherein the second balancing mass is arranged on the armature shaft at the side facing away from the eccentric or the eccentric bearing. Also a method for balancing such an electric motor is provided.

An electromagnetic propulsion unit for a land-based wheeled or tracked vehicle is provided. The propulsion unit includes a rotor stack, a rotor shaft, and a balancing plate assembly. The balancing plate assembly include a base plate fixating the rotor stack to the rotor shaft, where the base plate includes an air channel that axially extends through the base plate and a planar channel formed between the rotor stack and the base plate and in fluidic communication with the air channel.

An electromagnetic propulsion unit for a land-based wheeled or tracked vehicle is provided. The propulsion unit includes a rotor stack, a rotor shaft, and a balancing plate assembly. The balancing plate assembly include a base plate fixating the rotor stack to the rotor shaft, where the base plate includes an air channel that axially extends through the base plate and a planar channel formed between the rotor stack and the base plate and in fluidic communication with the air channel.

An electric compressor includes a housing, a drive shaft, a motor, a movable scroll, and a fixed block. The fixed block is fixed to the housing and disposed between the motor and the movable scroll. The motor includes a stator and a rotor. The rotor has an introduction passage that is formed through the rotor in an axial direction of the drive shaft. The drive shaft includes a balance weight that is disposed between the fixed block and the motor and extends to a position where the balance weight covers at least a part of the introduction passage in a radial direction of the drive shaft in a view in the axial direction. The introduction passage includes a first passage located outward of the balance weight in a circumferential direction of the rotor and the drive shaft, and a second passage facing the balance weight in the axial direction.

An electric compressor includes a housing, a drive shaft, a motor, a movable scroll, and a fixed block. The fixed block is fixed to the housing and disposed between the motor and the movable scroll. The motor includes a stator and a rotor. The rotor has an introduction passage that is formed through the rotor in an axial direction of the drive shaft. The drive shaft includes a balance weight that is disposed between the fixed block and the motor and extends to a position where the balance weight covers at least a part of the introduction passage in a radial direction of the drive shaft in a view in the axial direction. The introduction passage includes a first passage located outward of the balance weight in a circumferential direction of the rotor and the drive shaft, and a second passage facing the balance weight in the axial direction.

A compressor includes a shaft that is arranged along a rotation axis, a compression unit that drives along with rotation of the shaft, a rotor core that is fixed to the shaft, a plurality of permanent magnets that are embedded inside the rotor core, and a stator that causes the rotor core to rotate about the rotation axis, wherein a plurality of eccentric holes for adjusting balance when the shaft rotates are formed in the rotor core, and the plurality of eccentric holes are formed on an inner side of the polygonal region for which midpoints of sides at a side of the rotation axis among sides formed by side surfaces of the plurality of permanent magnet in a cross section perpendicular to the rotation axis serve as vertices.

A compressor includes a shaft that is arranged along a rotation axis, a compression unit that drives along with rotation of the shaft, a rotor core that is fixed to the shaft, a plurality of permanent magnets that are embedded inside the rotor core, and a stator that causes the rotor core to rotate about the rotation axis, wherein a plurality of eccentric holes for adjusting balance when the shaft rotates are formed in the rotor core, and the plurality of eccentric holes are formed on an inner side of the polygonal region for which midpoints of sides at a side of the rotation axis among sides formed by side surfaces of the plurality of permanent magnet in a cross section perpendicular to the rotation axis serve as vertices.