Laundry treating appliance

Patent metadata

Field	Value
Publication number	US-11976403-B2
Application number	US-202017621480-A
Country	US
Kind code	B2
Filing date	Jun 12, 2020
Priority date	Jun 21, 2019
Publication date	May 7, 2024
Grant date	May 7, 2024

Abstract

A laundry treating appliance having a tub, rotatable drum, at least one transmitter coil, at least one ring shaped housing on the drum perimeter and having an annular channel therein and at least one balancing unit disposed in the channel. The balancing unit has a receiver coil configured to receive wireless power from the transmitter coil and an actuator powered by the receiver coil, a sensing element to detect a position of the balancing unit in the housing, a balancing control unit configured to control the positioning of the balancing unit by driving the transmitter coil to send power to the receiver coil to operate the actuator on a friction force element to change the friction between the housing and the balancing unit.

First claim

The invention claimed is:

1. A laundry treating appliance comprising:
a tub,
a drum rotatably mounted inside the tub to rotate about a drum axis;
at least one transmitter coil configured to supply wireless electrical power;
at least one ring shaped housing mounted centred to the drum on a perimeter of the drum, the at least one ring shaped housing having an annular channel defined therein;
at least one balancing unit disposed in the annular channel and free to move under action of gravitational and/or inertial forces, the balancing unit having:
at least one receiver coil configured to receive power wirelessly from the transmitter coil,
an actuator configured to receive the power from the receiver coil,
a friction force element operatively positioned between the actuator and the at least one ring shaped housing,
a sensing element configured to detect a position of the at least one balancing unit in the housing, and
a balancing control unit configured to drive the transmitter coil to control a position of the at least one balancing unit in the at least one ring shaped housing,
wherein the actuator when powered from the transmitter coil via the receiver coil acts on the friction force element to change a friction force between the ring shaped housing and the balancing unit, thereby effecting a movement of the balancing unit in the annular channel.

2. The laundry treating appliance of claim 1 , wherein the balancing control unit is configured to drive the transmitter coil to control the position of the at least one balancing unit in the at least one ring shape housing based on one or more of: the position of the at least one balancing unit in the housing, an unbalance level of the drum, a drum position, and a drum speed.

3. The laundry treating appliance according to claim 1 , wherein:
the transmitter coil comprises transmitter coil windings arranged around a transmitter winding axis that is coaxial to the drum axis; and
each at least one receiver coil comprises respective receiver coil windings arranged around a respective receiver coil axis that is perpendicular to and extends radially to the drum axis, and wherein a projection of the receiver coil windings in a direction of the drum axis overlaps the transmitter coil windings.

4. The laundry treating appliance according to claim 3 , wherein the receiver coil windings and the transmitter coil windings are equidistant from the drum rotation axis in a direction radial to the drum rotation axis.

5. The laundry treating appliance according to claim 1 , wherein the friction element comprises a balancing unit wheel, and the actuator is configured to change a braking force of the balancing unit wheel.

6. The laundry treating appliance according to claim 1 , wherein the friction element comprises a portion of the actuator configured to push on one side of the housing.

7. The Laundry treating appliance according to claim 1 , wherein the friction element comprises a balancing unit wheel, and the actuator comprises an electromagnetic brake having an armature plate configured to act on a hub of the balancing unit wheel.

8. The laundry treating appliance according to claim 7 , wherein the friction element comprises a balancing unit wheel, and the actuator comprises an electrically-controlled clutch connecting a hub of the balancing unit wheel with a geared drive system.

9. The laundry treating appliance according to claim 1 , wherein the friction element comprises a balancing unit wheel, and the actuator comprises an electromagnetic actuator having a pin configured to engage a side opening in the balancing unit wheel.

10. The laundry treating appliance according to claim 1 , wherein the sensing element comprises at least one coil positioned on a stationary part of the appliance and configured to detect a voltage induced in the transmitter coil by the balancing unit receiver coil current.

11. The laundry treating appliance according to claim 1 , wherein the sensing element comprises an accelerometer positioned in the balancing unit, and wherein the position of the at least one balancing unit is calculated by a direction of a gravitational force.

12. The laundry treating appliance according to claim 1 , wherein the sensing element comprises a first accelerometer in a first balancing unit and the position of the at least one balancing unit in the housing is determined by a phase difference between a respective acceleration vector of the first accelerometer and a respective acceleration vector of a second accelerometer in a second balancing unit.

13. The laundry treating appliance according to claim 1 , wherein the at least one receiver coil comprises a plurality of receiver coils configured to form a resonant circuit.

14. The laundry treating appliance according to claim 13 , wherein a first balancing unit comprises at least one receiver coils configured to form a first resonant circuit having a first resonance frequency, and a second balancing unit comprises at least one receiver coil configured to form a second resonant circuit having a second resonance frequency, wherein the second resonance frequency is different from the first resonance frequency.

15. The laundry treating appliance according to claim 1 , wherein the transmitter coil is configured to transfer at wireless electrical power at at least two different power levels.

16. A method to control a laundry treating appliance comprising a tub, a drum rotatably mounted inside the tub to rotate about a drum axis, at least one transmitter coil configured to supply wireless electrical power, at least one ring shaped housing mounted centred to the drum on a perimeter of the drum, the at least one ring shaped housing having an annular channel defined therein, and at least two balancing units disposed in the annular channel and free to move under action of gravitational and/or inertial forces, wherein each balancing unit has at least one receiver coil configured to receive wireless power from the transmitter coil, wherein the two balancing units receiver coils are configured to resonate at different frequencies, and each has an actuator that, when powered from the transmitter coil, acts on a friction force element to change a friction force between the ring shaped housing and the balancing unit enabling or braking the balancing unit movement in the annular channel, a sensing element configured to detect the position of the balancing units in the housing, a balancing control unit configured to manage the positioning of the at least one balancing unit and to drive the transmitter coil based on the positions of the at least two balancing units, the unbalance level and or position estimated by a sensing element and the drum speed,
the method comprising:
rotating the drum at a constant speed that is higher than a predetermined laundry satellization speed to thereby brake the balancing units in the housing by friction between the friction force elements and the housing;
estimating the balancing units positions from the sensing element detection times or phase difference and the drum rotation period; and
moving one balancing unit forward or backward with respect the drum rotation direction, by operating the balancing control unit to reduce the friction force with the housing by transferring wireless power at the selected balancing unit receiver coils resonance frequency to power its actuator means, when its instantaneous speed component parallel to the gravitational force, during the drum rotation has the same direction of the gravitational force or opposite direction.

Assignees

• Electrolux Appliances AB

Inventors

• Chiriatti Antonio

Classifications

• D06F37/22 Primary

  in machines with a receptacle rotating or oscillating about a horizontal axis · CPC title

• D06F23/02

  and rotating or oscillating about a horizontal axis · CPC title

• D06F33/48

  Preventing or reducing imbalance or noise · CPC title

• D06F33/76

  Preventing or reducing imbalance or noise · CPC title

• D06F34/10

  Power supply arrangements, e.g. stand-by circuits · CPC title