Fan airflow monitoring system in an appliance

Patent metadata

Field	Value
Publication number	US-9535425-B2
Application number	US-201213473191-A
Country	US
Kind code	B2
Filing date	May 16, 2012
Priority date	May 16, 2012
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

An independent monitoring system and method for measuring the airflow rate in an appliance and determining its sufficiency is provided. An airflow detection system that monitors airflow rate (velocity) in an appliance is separate from the primary appliance control system and can determine whether a sufficient flow of air through air passageways occurs during operation of the appliance. An appliance component or subsystem can be controlled (e.g. activated or deactivated) by the airflow monitoring system based on the detected airflow rate.

First claim

What is claimed is:

1. An appliance, comprising:
an ambient air passageway defined in the appliance, the ambient air passageway configured to direct circulating ambient air around at least part of a chamber of the appliance;
a fan in communication with the ambient air passageway, the fan configured to selectively cause the ambient air to circulate through the ambient air passageway;
an appliance control system configured to control a speed of the fan based on an operating mode of the appliance; and
an airflow monitoring system in communication with the ambient air passageway, the airflow monitoring system configured to autonomously control a subsystem of the appliance based on a measured airflow rate within the ambient air passageway, the airflow monitoring system including
an airflow measuring device disposed at least partly within the ambient air passageway, the airflow measuring device configured to measure air velocity and determine the measured airflow rate through the ambient air passageway, and
an airflow monitoring controller configured to control the subsystem of the appliance based on the measured airflow rate by the airflow measuring device and compare the measured airflow rate by the airflow measuring device with a dynamic predetermined value of airflow velocity, where the dynamic predetermined value is dynamically determined according to a commanded fan speed;

wherein the appliance control system and the airflow monitoring system are both operably coupled to the subsystem of the appliance.

2. An appliance as in claim 1 , wherein the fan includes a multiple speed fan.

3. An appliance as in claim 1 , wherein the airflow monitoring controller is further configured to
control the subsystem of the appliance based on whether the measured airflow rate is less than or greater than the predetermined value.

4. An appliance as in claim 3 , wherein the airflow monitoring controller, upon determining that the measured airflow rate is less than the predetermined value, produces at least one of a visual indication signal, an audio indication signal, and an error signal to the appliance control system indicating that the measured airflow rate is less than the predetermined value.

5. An appliance as in claim 4 , wherein the error signal provided to the appliance control system indicating whether the measured airflow rate is less than the predetermined value causes the appliance control system to initiate at least one of a visual indicator, an audio indicator, and deactivation of power to at least a subsystem of the appliance.

6. An appliance as in claim 1 , wherein the commanded fan speed is provided to the airflow monitoring system by the appliance control system.

7. An appliance as in claim 1 , wherein the airflow monitoring system further comprises a fan speed detector in communication with the power signal to the fan, and the airflow monitoring system determines the commanded fan speed based on an output of the fan speed detector.

8. An appliance as in claim 1 , wherein the airflow monitoring system further comprises a power control device and the power control device controls the subsystem of the appliance based on the measured airflow rate by the airflow measuring device.

9. An appliance as in claim 8 , wherein the power control device disengages the subsystem of the appliance if the measured airflow rate by the airflow measuring device is less than the predetermined value.

10. An appliance as in claim 1 , wherein the airflow monitoring system is disposed separately from the appliance control system within the appliance.

11. A method for controlling one or more subsystems of an appliance based on a measured airflow rate around at least part of a chamber of the appliance, comprising
monitoring the measured airflow rate circulating through an ambient air passageway at an airflow monitoring system, where a fan circulates ambient air through the ambient air passageway at the measured airflow rate based on commands from an appliance control system according to an appliance operating mode, including determining the measured airflow rate at an airflow measuring device and comparing the measured airflow rate by the airflow measuring device with a dynamic predetermined value of airflow velocity, where the dynamic predetermined value is dynamically determined according to a commanded fan speed; and
autonomously controlling a the one or more subsystems of the appliance based on the measured airflow rate using the airflow monitoring system,
wherein the appliance control system and the airflow monitoring system are both operably coupled to the one or more subsystems of the appliance.

12. A method as in claim 11 , wherein monitoring the measured airflow rate circulating through the ambient air passageway at the airflow monitoring system comprises:
determining a speed the fan is operating at to circulate ambient air through the ambient air passageway; and
communicating the measured airflow rate and the fan speed to an airflow monitoring controller.

13. A method as in claim 12 , wherein determining the speed the fan is operating at to circulate ambient air through the ambient air passageway comprises receiving a commanded fan speed signal at the airflow monitoring system from the appliance control system.

14. A method as in claim 12 , wherein determining the speed the fan is operating at to circulate ambient air through the ambient air passageway comprises detecting a fan speed at the airflow monitoring system using a fan speed detector.

15. A method as in claim 12 , wherein controlling the appliance based on the measured airflow rate using the airflow monitoring system comprises:
controlling the appliance when the measured airflow rate is less than the predetermined value.

16. A method as in claim 15 , wherein controlling the appliance when the measured airflow rate is less than the predetermined value comprises deactivating the one or more subsystems of the appliance using a power control device.

17. A method as in claim 11 , wherein the predetermined value is based on a speed of the fan.

18. A method as in claim 11 , further comprising initiating an error indication based on the measured airflow rate.

19. A method as in claim 18 , wherein initiating an error indication based on the measured airflow rate comprises
sending an error signal from the airflow monitoring system to the appliance control system when the measured airflow rate is less than a predetermined value; and
initiating a remedial action at the appliance control system after the appliance control system receives the error signal.

20. A method as in claim 19 , wherein initiating a remedial action at the appliance control system comprises initiating at least one of a visual indicator, an audio indicator, and deactivation of power to at least part of the appliance.

Assignees

• Bach James Carter
• Burt Ashley Wayne
• Haier Us Appliance Solutions Inc

Inventors

• Bach James Carter
• Burt Ashley Wayne

Classifications

• G05D23/19

  characterised by the use of electric means {(G05D23/1393 takes precedence)} · CPC title

• G05D7/0682 Primary

  using a plurality of flow sources · CPC title

• F24F2011/0038

  Mechanical Engineering · mapped topic

• F24F2110/30

  Velocity · CPC title