Abstract: In an electric motor, a first magnet and a second magnet are accommodated in magnet accommodating apertures of a rotor core. On outer circumferential core portions that exist on a radially outer side of the magnet accommodating apertures, two slits as a pair of first slits, and two slits that are respectively adjacent to each of the first slits are disposed circumferentially outside the pair of first slits as a pair of second slits. The outer circumferential core portions include: a first magnetic portion that exists between the pair of first slits; and a pair of second magnetic portions that respectively exist between the first slits and the second slits. An inter-magnet space portion that exists between the first magnet and the second magnet is positioned within a range of the first magnetic portion in the circumferential direction of the rotor.

Abstract: A driving device drives a motor having coils. The driving device includes a converter to generate a bus voltage, an inverter to convert the bus voltage to an AC voltage and supply the AC voltage to the coils, and a connection switching unit to switch a connection state of the coils. The bus voltage generated by the converter is switched in accordance with the connection state of the coils.

Abstract: A stator core includes a first core portion including a plurality of first plates stacked in a first direction; a second core portion including a plurality of second plates stacked in the first direction; and a third core portion including a plurality of third plates stacked in at least one direction orthogonal to the first direction, the third core portion being sandwiched between the first core portion and the second core portion. The third core portion has a yoke portion formed of a subset of the plurality of third plates stacked in a second direction orthogonal to the first direction.

Abstract: A stator includes a first core including a plurality of non-oriented electromagnetic steel sheets that is stacked and having an insertion hole penetrating the plurality of non-oriented electromagnetic steel sheets in an axial direction of the stator and a second core arranged in the insertion hole and including a plurality of oriented electromagnetic steel sheets that is stacked. The first core has a thin-wall part adjoining the second core, and a conditional expression of 0.5tm?ta?2tm is satisfied, where ta denotes a thickness of the thin-wall part when the first core is viewed in the axial direction and tm denotes a sheet thickness of one non-oriented electromagnetic steel sheet in the plurality of non-oriented electromagnetic steel sheets.

Abstract: A rotor includes a cylindrical a rotor core having a plurality of magnet insertion holes extending along a central axis of the cylindrical shape and permanent magnets inserted into the magnet insertion holes, respectively. A slit extending along the central axis is provided between an outer circumferential surface of the rotor core and at least one of the magnet insertion holes. The slit inner lines extend toward the outer circumferential surface of the rotor core from the apex of the slit, the apex being located on a side of the magnet insertion holes. The slit outer line connects side ends of the slit inner lines located on a side opposite to the apex.

Abstract: A driving device includes a connection switching unit to switch a connection state of coils between a first connection state and a second connection state in which a line voltage is lower than in the first connection state, a controller to control a motor and the connection switching unit, and a rotation speed detector to detect a rotation speed of the motor. When the connection state of the coils is the first connection state and the rotation speed detected by the rotation speed detector becomes higher than or equal to a first rotation speed, the controller causes the motor to rotate at a second rotation speed higher than the first rotation speed, and then causes the connection switching unit to switch the connection state of the coils from the first connection state to the second connection state.

Abstract: A driving device includes a connection switching unit that switches connection condition of a coil between Y connection and delta connection, an inverter, and a control device that controls a carrier frequency of the inverter. The carrier frequency is set at a first carrier frequency when the connection condition of the coil is the Y connection. The carrier frequency is set at a second carrier frequency when the connection condition of the coil is the delta connection.

Abstract: A driving device includes an inverter to output a voltage to coils, a connection switching unit to switch a connection state of the coils between a Y connection and a delta connection, and a controller. The controller causes the inverter to stop outputting, when the connection state of the coils is the Y connection and a current value of the inverter reaches a first threshold A, or when the connection state of the coils is the delta connection and the current value of the inverter reaches a second threshold B. The first threshold A and the second threshold B satisfy B<?3×A.

Abstract: Provided is an interior permanent magnet motor, including: a stator; and a rotor, in which an outline of each of magnet insertion holes includes a radially inner-side line, a radially outer-side line, a pair of side lines, a pair of first round portions, and a pair of second round portions, in which a thin portion is formed between an outer peripheral surface of the rotor and each of the side lines, in which each of the first round portions is provided between a corresponding end of the corresponding radially outer-side line and a corresponding end of the corresponding side line, and in which each of the second round portions is provided between a corresponding end of the corresponding radially inner-side line and a corresponding end of the corresponding side line.

Abstract: A stator includes a yoke portion, and a tooth portion located inside the yoke portion in a radial direction. A fracture surface ratio of an inner surface of the tooth portion in the radial direction is lower than a fracture surface ratio of a side surface of the yoke portion.

Abstract: A rotor of a permanent-magnet-embedded electric motor includes an annular rotor core having a plurality of magnet insertion holes formed in a circumferential direction, and permanent magnets inserted into the magnet insertion holes, respectively. The rotor core is formed by alternately stacking a first core block and a second core block in an axial direction of the rotor core, the first core block not having slits between each of the magnet insertion holes and a circumferential surface of the rotor core, and the second core block having the slits between each of the magnet insertion holes and the circumferential surface of the rotor core. One of the slits and one end of the permanent magnet are arrayed in a radial direction, and the other slit and the other end of the permanent magnet are arrayed in the radial direction.

Abstract: An air conditioner includes a compressor having a compressor motor including coils, an indoor fan having a fan motor, a connection switching unit that switches a connection state of the coils between a first connection state and a second connection state in which a line voltage is lower than a line voltage in the first connection state, and a controller that controls the compressor motor, the fan motor, and the connection switching unit. The controller provides a stop period during which rotation of the compressor motor stops before the connection switching unit switches the connection state of the coils, and rotates the fan motor for at least a time period within the stop period.

Abstract: A driving device is used with a compressor including a motor including coils. The driving device drives the motor. The driving device includes an inverter connected to the coils, a connection switching unit to switch a connection state of the coils between a first connection state and a second connection state, a controller to control the inverter and the connection switching unit, and a compressor state detection unit to detect a state of the compressor. When the connection state of the coils is the first connection state, the controller controls the motor based on a first detection value detected by the compressor state detection unit and a first threshold. When the connection state of the coils is the second connection state, the controller controls the motor based on a second detection value detected by the compressor state detection unit and a second threshold.

Abstract: A driving device drives a motor having coils. The driving device includes a converter to generate a bus voltage, an inverter to convert the bus voltage to an AC voltage and supply the AC voltage to the coils, and a connection switching unit to switch a connection state of the coils. The bus voltage generated by the converter is switched in accordance with the connection state of the coils.

Abstract: A stator core includes a first core portion including a plurality of first plates stacked in a first direction; a second core portion including a plurality of second plates stacked in the first direction; and a third core portion including a plurality of third plates stacked in at least one direction orthogonal to the first direction, the third core portion being sandwiched between the first core portion and the second core portion. The third core portion has a yoke portion formed of a subset of the plurality of third plates stacked in a second direction orthogonal to the first direction.

Abstract: A motor includes a stator, a rotor including a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other. The rotor core has a first magnet holding portion in the magnet insertion hole, and a second magnet holding portion at an end of the magnet insertion hole in a circumferential direction. The rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction. Relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets is represented by A, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C.

Abstract: A stator includes a winding and a plurality of split core parts arranged annularly in a circumferential direction around an axis line. Each of the plurality of split core parts includes a yoke part, a tooth part, a connection part including a curved surface, and a first insulator provided on an end part of the tooth part. The first insulator includes a first protruding part protruding beyond the curved surface.

Abstract: A driving device drives a motor having coils. The driving device includes a connection switching unit to switch a connection state of the coils, a temperature sensor to detect a room temperature, and a controller to switch the connection state of the coils based on a detected temperature by the temperature sensor.

Abstract: An air conditioner includes a signal receiving unit to receive an operation instruction signal, a compressor including a motor including coils, an inverter connected to the coils, a connection switching unit to switch a connection state of the coils between a first connection state and a second connection state, and a controller to control the inverter and the connection switching unit. When the signal receiving unit receives an operation stop signal, the connection switching unit switches the connection state of the coils from the first connection state to the second connection state.

Abstract: A stator includes: a stator core including a first core part formed by at least one first sheet and a second core part provided on a side face of the first core part and formed by at least one second sheet; and a winding wound around an outer periphery of the first core part and the second core part.