Hybrid RF/conventional clothes dryer

Patent metadata

Field	Value
Publication number	US-11066778-B2
Application number	US-201916694633-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Oct 30, 2015
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

The present application encompasses methods and apparatus for heating a load such as clothes immersed in a medium such as water during a heating period. A method embodiment of the present invention comprises heating the load and medium within an enclosure by subjecting said load and medium to heated air originated from a conventional energy source; and applying heat to said load and medium within the enclosure via an AC electrical field, embodied as a capacitor, originated from an RF power source.

First claim

What is claimed is:

1. An apparatus for heating a load including an absorbed medium, comprising:
a conventional energy source configured to heat air and to supply the heated air into an enclosure that accommodates the load and medium therein;
a radio frequency (RF) energy source configured to apply heat to the load and medium within the enclosure via an alternating current (AC) electrical field embodied as a capacitor;
a valve configured to, based on the RF energy source being turned on to perform RF dielectric heating of the enclosure, be opened to allow air heated by recovered heat from the RF energy source to be supplied to the enclosure; and
an air blower configured to suction air out of the enclosure and to generate an output air flow, wherein the enclosure is located between the valve and the air blower.

2. The apparatus of claim 1 , further comprising:
a heat recovery plenum configured to absorb heat from the RF energy source; and
coupled to the heat recovery plenum, means for imparting heated air from proximate the heat recovery plenum into the enclosure.

3. The apparatus of claim 1 , wherein the load comprises clothes to be dried.

4. The apparatus of claim 1 , wherein the RF energy source is a solid state RF signal generator configured to operate at a single frequency.

5. The apparatus of claim 1 , wherein the apparatus is controlled by taking realtime RF impedance measurements to determine load and medium status including moisture level, and by controlling parameters of the RF energy source and the conventional energy source in realtime based upon the realtime RF impedance measurements.

6. The apparatus of claim 1 , wherein a power level of at least one of the conventional energy source or the RF energy source is varied during a heating period.

7. The apparatus of claim 6 , wherein the power level is varied by turning at least one of the conventional energy source or the RF energy source off.

8. The apparatus of claim 1 , wherein a rate of air flow through the enclosure is varied by controlling speed of the blower.

9. The apparatus of claim 1 , wherein a heating period is broken into discrete phases, and each phase comprises activating at least one of the conventional energy source or the RF energy source.

10. The apparatus of claim 1 , wherein the air flow through the enclosure is used to recover heat produced by temperature increases in at least one of the load, medium, and RF power source.

11. The apparatus of claim 1 , wherein:
the enclosure is configured to rotate during at least a portion of a heating period;
the heating period is broken into phases; and
each phase comprises at least one of a different speed or a direction to a rotation of the enclosure.

12. The apparatus of claim 1 , wherein the air heated by the recovered heat from the RF energy source is applied to the load and medium within the enclosure.

13. The apparatus of claim 12 , wherein:
heated air from the conventional energy source and recovered heated air from the RF energy source are each sent to the enclosure via a dedicated air channel; and
air flow within at least one air channel is regulated.

14. The apparatus of claim 13 , wherein the air flow within at least one air channel is regulated by opening or closing a valve situated within each air channel.

15. The apparatus of claim 13 , wherein a heating period is broken into phases, and each phase comprises forcing a different rate of air flow through two dedicated air channels.

16. The apparatus of claim 1 , wherein a duration and other parameters of a heating period are controlled by a preselected algorithm based upon desired results, wherein the desired results include at least one of speed, efficiency, and degree of care to be accorded to the load.

17. The apparatus of claim 16 , wherein the other parameters include at least one of power levels of each of the conventional energy source or the RF energy source, flow of heated air from the conventional energy source, and flow of recovered heated air from the RF energy source.

18. The apparatus of claim 1 , wherein the apparatus is controlled based upon at least one of estimates of power, time, energy, temperature at an input to a drum, temperature at an output to the drum, realtime RF sensing, or empirical data from previous RF measurements.

19. The apparatus of claim 1 , wherein the RF energy source is configured to:
perform the dielectric heating of the enclosure by applying an RF waveform to the medium absorbed in the load to thereby vaporize the medium; and
discharge heat to an outside of the enclosure during the performance of the dielectric heating, and
wherein the recovered heat from the RF energy source includes at least a portion of the heat discharged from the RF energy source during the performance of the dielectric heating.

20. An apparatus for heating a load including an absorbed medium, comprising:
a conventional energy source configured to heat air and to supply the heated air into an enclosure that accommodates the load and medium therein;
an air valve configured to, based on the conventional energy source being turned on, be opened to allow air heated by the conventional energy source to be supplied to the enclosure;
a radio frequency (RF) energy source configured to apply heat to the load and medium within the enclosure via an alternating current (AC) electrical field embodied as a capacitor; and
an air blower configured to suction air out of the enclosure and to generate an output air flow, wherein the enclosure is located between the air valve and the air blower,
wherein the RF energy source performs RF dielectric heating of the enclosure.

Assignees

• Lg Electronics Inc
• Cool Dry Inc

Inventors

• D'Anna Pablo E
• Wisherd David S
• Wohl Michael Andrew
• Decker Edward Herman
• Cox Gary Lynn

Classifications

• D06F2103/64

  Radiation, e.g. microwaves · CPC title

• D06F2105/28

  Electric heating · CPC title

• D06F2103/38

  Time, e.g. duration · CPC title

• F26B3/04

  the gas or vapour circulating over or surrounding the materials or objects to be dried (F26B3/14 takes precedence) · CPC title

• D06F2103/44

  Current or voltage · CPC title