Washing machine drive system
A washing machine drive system is provided. A washing machine drive system according to an aspect of the present disclosure includes a housing, a motor stator coupled to the housing, a rotor facing the motor stator, an output shaft bearing-coupled to the housing, a planetary gear set coupled to the rotor and spline-coupled to an outer peripheral surface of the output shaft, a clutch stator coupled to the motor stator, and a clutch actuator spline-coupled to an outer peripheral surface of the planetary gear set so as to be vertically movable and facing the clutch stator, in which the clutch stator includes first to third coils arranged in parallel in a vertical direction, the clutch actuator is fixed to the rotor and transmits rotational force of the rotor to the output shaft at a 1:1 ratio when current is supplied to the first coil, the clutch actuator is fixed to the clutch stator, reduces the rotational force of the rotor at a gear ratio of n:1, and transmits the reduced rotational force to the output shaft when current is supplied to the third coil, and the clutch actuator is disengaged from the rotor or the clutch stator when current is supplied to the second coil.
1 . A washing machine drive system comprising:
a housing;
a motor stator to couple to the housing;
a rotor to face the motor stator;
an output shaft to bearing-couple to the housing;
a planetary gear set to couple to the rotor and to spline-couple to an outer surface of the output shaft;
a clutch stator to couple to the motor stator; and
a clutch actuator to spline-couple to an outer surface of the planetary gear set, and the clutch actuator is configured to be movable and face the clutch stator,
wherein the clutch stator includes a first coil, a second coil and a third coil arranged in a first direction,
the clutch actuator is configured such that:
when current is supplied to the first coil, the clutch actuator is to be fixed to the rotor and a rotational force of the rotor is provided to the output shaft at a 1:1 ratio,
when current is supplied to the third coil, the clutch actuator is to be fixed to the clutch stator, the rotational force of the rotor is reduced at a gear ratio of n:1, and the reduced rotational force is provided to the output shaft, and
when current is supplied to the second coil, the clutch actuator is to disengage from the rotor or the clutch stator.
2 . The washing machine drive system of claim 1 , wherein the planetary gear set includes:
a sun gear to couple to the rotor,
a plurality of pinion gears to couple to an outer surface of the sun gear, and the plurality of pinion gears are spaced apart in a circumferential direction,
a ring gear having an inner surface to couple to the plurality of pinion gears and having an outer surface to spline-couple to the clutch actuator, and
a carrier to couple to the plurality of pinion gears and to spline-couple to the outer surface of the output shaft.
3 . The washing machine drive system of claim 2 , wherein the planetary gear set includes a sun gear bearing arranged between the carrier and the sun gear.
4 . The washing machine drive system of claim 3 , wherein the sun gear bearing overlaps the first and second coils in a second direction perpendicular to a longitudinal direction of the output shaft.
5 . The washing machine drive system of claim 2 , wherein the planetary gear set includes a ring gear bearing arranged between the carrier and the ring gear.
6 . The washing machine drive system of claim 2 , wherein a center area of the plurality of pinion gears is arranged between the first coil and the second coil in a second direction perpendicular to a longitudinal direction of the output shaft.
7 . The washing machine drive system of claim 2 , wherein the plurality of pinion gears overlap the first and second coils in a second direction perpendicular to a longitudinal direction of the output shaft, and the plurality of pinion gears do not overlap the third coil in the second direction.
8 . The washing machine drive system of claim 2 , wherein
an upper surface of the ring gear overlaps the third coil in a second direction perpendicular to a longitudinal direction of the output shaft, and
a lower surface of the ring gear is arranged below the first coil.
9 . The washing machine drive system of claim 1 , wherein the clutch actuator includes a first clutch portion disposed on an upper surface of the clutch actuator,
the clutch stator includes a second clutch portion disposed on a surface facing the upper surface of the clutch actuator, and
when current is supplied to the third coil, the first clutch portion is to couple to the second clutch portion.
10 . The washing machine drive system of claim 9 , wherein the clutch actuator includes a third clutch portion disposed on a lower surface of the clutch actuator,
the rotor includes a fourth clutch portion disposed on a surface facing the lower surface of the clutch actuator, and
when current is supplied to the first coil, the third clutch portion is to couple to the fourth clutch portion.
11 . The washing machine drive system of claim 1 , wherein the clutch actuator includes a clutch coupling portion to spline-connect to the planetary gear set, and a clutch magnet disposed in the clutch coupling portion and to face the clutch stator,
when current is supplied to the first coil and then the supply of current is stopped, coupling of the clutch actuator and the rotor is maintained,
when current is supplied to the third coil and then the supply of current is stopped, coupling of the clutch actuator and the clutch stator is maintained, and
when current is supplied to the second coil and then the supply of current is stopped, decoupling of the clutch actuator and the rotor or the clutch stator is maintained.
12 . The washing machine drive system of claim 11 , wherein a length of the clutch magnet is between 1.8 and 2.2 times a length of each of the first coil, the second coil and the third coil.
13 . The washing machine drive system of claim 1 , wherein the clutch stator includes a stator coupling portion to couple to the motor stator, and a first core, a second core and a third core arranged in the stator coupling portion and arranged in the first direction or parallel to the first direction,
the first coil is arranged in the first core, the second coil is arranged in the second core, and the third coil is arranged in the third core, and
the first, second, and third cores are each formed in a same shape, and the first, second, and third coils are each formed in a same shape.
14 . The washing machine drive system of claim 13 , wherein the stator coupling portion includes a circumferential portion that extends inwardly in a circumferential direction from an upper surface of the stator coupling portion,
a second clutch portion is arranged on a lower surface of the circumferential portion, and
the second clutch portion overlaps the clutch actuator in the first direction or parallel to the first direction.
15 . The washing machine drive system of claim 13 , wherein the clutch actuator includes a clutch coupling portion to spline-couple to the planetary gear set, and a clutch magnet disposed in the clutch coupling portion and to face the clutch stator,
when current is supplied to the first coil, the clutch magnet is to overlap the first coil, the second coil, the first core, and the second core in a second direction,
when current is supplied to the second coil, the clutch magnet is to overlap the second coil, the first core, the second core and the third core in the second direction, and
when current is supplied to the third coil, the clutch magnet is to overlap the second coil, the third coil, the second core, and the third core in the second direction.
16 . The washing machine drive system of claim 13 , wherein the clutch actuator includes a clutch coupling portion to spline-couple to the planetary gear set, and a clutch magnet disposed in the clutch coupling portion and to face the clutch stator,
when current is supplied to the first coil, a center region of the clutch magnet is to overlap an upper region of the first coil in a second direction,
when current is supplied to the second coil, the center region of the clutch magnet is to overlap a center region of the second coil in the second direction, and
when current is supplied to the third coil, the center region of the clutch magnet is to overlap a lower region of the third coil in the second direction.
17 . The washing machine drive system of claim 1 , wherein the clutch actuator and the clutch stator are disposed between the planetary gear set and the motor stator in a second direction perpendicular to a longitudinal direction of the output shaft.
18 . The washing machine drive system of claim 1 , wherein the rotor includes a rotor case including a disk portion having a center to be shared with the output shaft and a cylindrical portion that extends upward from a radially outer side of the disk portion, and a rotor magnet disposed in the cylindrical portion and to face the motor stator, and
the rotor magnet is to overlap the second and third coils in a second direction perpendicular to a longitudinal direction of the output shaft, and the rotor magnet does not overlap the first coil in the second direction.
19 . A washing machine drive system comprising:
a housing;
a motor stator to couple to the housing;
a rotor to face the motor stator;
a shaft to couple to the housing;
a planetary gear set to couple to the rotor and to couple to the shaft;
a clutch stator to couple to the motor stator; and
a clutch actuator to couple to the planetary gear set, and the clutch actuator is configured to be movable and face the clutch stator,
wherein the clutch stator includes a first coil, a second coil and a third coil,
based on current at the first coil, a rotational force of the rotor is to be provided to the shaft at a 1:1 ratio,
based on current at the third coil, a reduced rotational force of the rotor at a gear ratio of n:1 is to be provided to the shaft, and
based on current at the second coil, the clutch actuator is to disengage from the rotor or the clutch stator.
20 . The washing machine drive system of claim 19 , wherein the clutch actuator includes a first clutch portion disposed on an upper surface of the clutch actuator and a third clutch portion disposed on a lower surface of the clutch actuator,
the clutch stator includes a second clutch portion facing the upper surface of the clutch actuator,
the rotor includes a fourth clutch portion facing the lower surface of the clutch actuator,
based on current at the third coil, the first clutch portion is to couple to the second clutch portion, and
based on current at the first coil, the third clutch portion is to couple to the fourth clutch portion.