Abstract: A brushless motor (18) which supplies currents to coils (U1, U2, V1, V2, W1, and W2) and rotates a rotor (27), the brushless motor comprising a control apparatus (37) which switches and selectively executes: first energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at first timing, and to continue the energization for a first period to control the rotation number of the rotor (27); and second energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at second timing advanced by an electric angle with respect to the first timing, and to continue the energization for a second period longer than the first period to control the rotation number of the rotor (27).

Abstract: Since a shape of a stator 44 is made mirror symmetric with respect to a rotor 45 as a 4-pole/6-slot type, rotational deflection of the rotor 45 can be suppressed. As the minimum number of poles and the minimum number of slots, which can suppress the rotational deflection of the rotor 45, a frequency of magnetic noises approaches a frequency of mechanical noises. Thus, it is possible to integrate the whole noises generated by the DR-side wiper motor 21 into a low frequency range thereof, and to make the acoustic sensitivity (dB) of a vehicle interior smaller. Since the stator 44 is fixed inside a housing 40 and mounting legs fixed to a vehicle body fixed portion are provided in the housing 40, the stator 40, which is a source of the magnetic noises, can be fixed to a vehicle via only the housing 40. Therefore, a brushless wiper motor with quietness improved further can be designed.

Abstract: A motor control apparatus that controls a brushless motor which operates a wiper arm so as to swing, the motor control apparatus including: a position detection part that detects a rotation position of a rotor; and a control part that performs a sine wave drive of the brushless motor at a time of a low output mode in which an output of the brushless motor is low and that, at a time of a high output mode in which an output is higher than an output at the time of the low output mode, allows a power distribution angle to be an angle that is larger than 120 degrees and distributes power to the brushless motor at a timing when a predetermined electric angle is advanced with reference to the rotation position of the rotor.

Abstract: A brushless motor (18) which supplies currents to coils (U1, U2, V1, V2, W1, and W2) and rotates a rotor (27), the brushless motor comprising a control apparatus (37) which switches and selectively executes: first energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at first timing, and to continue the energization for a first period to control the rotation number of the rotor (27); and second energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at second timing advanced by an electric angle with respect to the first timing, and to continue the energization for a second period longer than the first period to control the rotation number of the rotor (27).

Abstract: Since a shape of a stator 44 is made mirror symmetric with respect to a rotor 45 as a 4-pole/6-slot type, rotational deflection of the rotor 45 can be suppressed. As the minimum number of poles and the minimum number of slots, which can suppress the rotational deflection of the rotor 45, a frequency of magnetic noises approaches a frequency of mechanical noises. Thus, it is possible to integrate the whole noises generated by the DR-side wiper motor 21 into a low frequency range thereof, and to make the acoustic sensitivity (dB) of a vehicle interior smaller. Since the stator 44 is fixed inside a housing 40 and mounting legs fixed to a vehicle body fixed portion are provided in the housing 40, the stator 40, which is a source of the magnetic noises, can be fixed to a vehicle via only the housing 40. Therefore, a brushless wiper motor with quietness improved further can be designed.

Abstract: A motor case (31) in which a stationary portion (35) is fixed, and a gear case (41) in which a gear mechanism (SD) is accommodated are made of aluminium, most heat generated from the stationary portion (35) at the time of actuation of a brushless wiper motor (20) can be directly dissipated outside from the motor case (31). That is, compared with conventional technique, heat transmitted to the motor case (31) can be efficiently dissipated outside, and the motor case (31) does not reach high temperature. Therefore, as a matter of course, reduction in size and weight can be achieved, suppression of electromagnetic noise can be achieved, and heat-resistance strength can be enhanced. Expensive components capable of resisting high temperatures are not required, and reduction in manufacturing cost can be achieved.

Abstract: Since a shape of a stator 44 is made mirror symmetric with respect to a rotor 45 as a 4-pole/6-slot type, rotational deflection of the rotor 45 can be suppressed. As the minimum number of poles and the minimum number of slots, which can suppress the rotational deflection of the rotor 45, a frequency of magnetic noises approaches a frequency of mechanical noises. Thus, it is possible to integrate the whole noises generated by the DR-side wiper motor 21 into a low frequency range thereof, and to make the acoustic sensitivity (dB) of a vehicle interior smaller. Since the stator 44 is fixed inside a housing 40 and mounting legs fixed to a vehicle body fixed portion are provided in the housing 40, the stator 40, which is a source of the magnetic noises, can be fixed to a vehicle via only the housing 40. Therefore, a brushless wiper motor with quietness improved further can be designed.

Abstract: Since a shape of a stator 44 is made mirror symmetric with respect to a rotor 45 as a 4-pole/6-slot type, rotational deflection of the rotor 45 can be suppressed. As the minimum number of poles and the minimum number of slots, which can suppress the rotational deflection of the rotor 45, a frequency of magnetic noises approaches a frequency of mechanical noises. Thus, it is possible to integrate the whole noises generated by the DR-side wiper motor 21 into a low frequency range thereof, and to make the acoustic sensitivity (dB) of a vehicle interior smaller. Since the stator 44 is fixed inside a housing 40 and mounting legs fixed to a vehicle body fixed portion are provided in the housing 40, the stator 40, which is a source of the magnetic noises, can be fixed to a vehicle via only the housing 40. Therefore, a brushless wiper motor with quietness improved further can be designed.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: A brushless motor (18) which supplies currents to coils (U1, U2, V1, V2, W1, and W2) and rotates a rotor (27), the brushless motor comprising a control apparatus (37) which switches and selectively executes: first energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at first timing, and to continue the energization for a first period to control the rotation number of the rotor (27); and second energization control to start energization to the coils (U1, U2, V1, V2, W1, and W2) at second timing advanced by an electric angle with respect to the first timing, and to continue the energization for a second period longer than the first period to control the rotation number of the rotor (27).

Abstract: A motor case (31) in which a stationary portion (35) is fixed, and a gear case (41) in which a gear mechanism (SD) is accommodated are made of aluminium, most heat generated from the stationary portion (35) at the time of actuation of a brushless wiper motor (20) can be directly dissipated outside from the motor case (31). That is, compared with conventional technique, heat transmitted to the motor case (31) can be efficiently dissipated outside, and the motor case (31) does not reach high temperature. Therefore, as a matter of course, reduction in size and weight can be achieved, suppression of electromagnetic noise can be achieved, and heat-resistance strength can be enhanced. Expensive components capable of resisting high temperatures are not required, and reduction in manufacturing cost can be achieved.

Abstract: A brushless motor comprises: a stator 21 having armature coils 21a, 21b, and 21c; a rotor 22 which is rotated by a revolving magnetic field; and a switching element 30a, wherein the brushless motor has a rotation number control unit 33 which switches between low-speed and high-speed mode, wherein in the low-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at predetermined energization timing and controls a duty ratio to control the rotation number of the rotor 22, and in the high-speed mode, the rotation number control unit 33 supplies current to the armature coils 21a, 21b, and 21c at energization timing advanced from the energization timing for the low-speed mode, thereby performing field weakening control of weakening the revolving magnetic field from that of the low-speed mode to control the rotation number of the rotor 22.

Abstract: In an electric motor, permanent magnets are disposed on flat sections of a peripheral wall of the yoke, which is formed to be polygonal seen in plan view in the axial direction, a first bearing section which rotatably supports one end of the rotary shaft is integrally formed on a bottom part of the yoke, and a brush holder accommodating section capable of accommodating a brush holder unit that holds the brushes is integrally formed at an opening of the yoke.