A brushless motor, comprising: a stator having a three-phase winding; a rotor that has a permanent magnet and that is rotated in a state of facing the stator; an inverter that has a plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) and is configured to supply an AC current to the three-phase wiring by turning on or turning off the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2); and a control part configured to control an ON or OFF state of the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) by switching a power distribution pattern that represents a change of a power distribution state of each phase of the three-phase wiring in response to a rotation of the rotor to a low-speed power distribution pattern in use for a low-speed power distribution control or a high-speed power distribution pattern in use for a high-speed power distribution control, characterized in that the control part is configured to switch the power distribution pattern to the low-speed power distribution pattern in a case where a rotation speed of the rotor is less than a predetermined threshold value, and the control part switches the power distribution pattern to the high-speed power distribution pattern when a state in which a load of the rotor is within a predetermined range is continued for a predetermined period of time in a case where the rotation speed of the rotor is equal to or more than the threshold value, the control part is configured to control a duty ratio to be equal to or less than a predetermined limit value by using a pulse width modulation such that a rotation speed of the rotor becomes a predetermined target value when controlling the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) to be in an ON or OFF state, the control part is configured to set a high-speed power distribution control switching timer value to a predetermined value when the duty ratio for allowing the rotation speed of the rotor to be the target value is greater than or equal to the predetermined limit value, the control part is configured to reduce the high-speed power distribution control switching timer value according to the number of times that the duty ratio is less than the limit value, and the control part is configured to determine that a state in which the load of the rotor is within the predetermined range is continued for the predetermined period of time when the high-speed power distribution control switching timer value is equal to zero. a stator having a three-phase winding; a rotor that has a permanent magnet and that is rotated in a state of facing the stator; an inverter that has a plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) and is configured to supply an AC current to the three-phase wiring by turning on or turning off the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2); and a control part configured to control an ON or OFF state of the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) by switching a power distribution pattern that represents a change of a power distribution state of each phase of the three-phase wiring in response to a rotation of the rotor to a low-speed power distribution pattern in use for a low-speed power distribution control or a high-speed power distribution pattern in use for a high-speed power distribution control, the control part is configured to switch the power distribution pattern to the low-speed power distribution pattern in a case where a rotation speed of the rotor is less than a predetermined threshold value, and the control part switches the power distribution pattern to the high-speed power distribution pattern when a state in which a load of the rotor is within a predetermined range is continued for a predetermined period of time in a case where the rotation speed of the rotor is equal to or more than the threshold value, the control part is configured to control a duty ratio to be equal to or less than a predetermined limit value by using a pulse width modulation such that a rotation speed of the rotor becomes a predetermined target value when controlling the plurality of switching elements (11u1, 11u2, 11v1, 11v2, 11w1, 11w2) to be in an ON or OFF state, the control part is configured to set a high-speed power distribution control switching timer value to a predetermined value when the duty ratio for allowing the rotation speed of the rotor to be the target value is greater than or equal to the predetermined limit value, the control part is configured to reduce the high-speed power distribution control switching timer value according to the number of times that the duty ratio is less than the limit value, and the control part is configured to determine that a state in which the load of the rotor is within the predetermined range is continued for the predetermined period of time when the high-speed power distribution control switching timer value is equal to zero.