Motor controller for draft inducer motor in a furnace and method of use

Patent metadata

Field	Value
Publication number	US-11268694-B2
Application number	US-201816037543-A
Country	US
Kind code	B2
Filing date	Jul 17, 2018
Priority date	Jul 17, 2018
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

A motor controller for a draft inducer motor that operates an inducer blower in a furnace is provided. The motor controller includes a communication interface operable to receive a signal from a system controller. The signal represents a command to operate the draft inducer motor. The motor controller includes a processor operable to operate the draft inducer motor in accordance with a predefined motor speed profile during at least one of an ignition stage and a combustion stage of the furnace.

First claim

What is claimed is:

1. A motor controller for a draft inducer motor that operates an inducer blower in a furnace, said motor controller comprising:
a memory configured to store a predefined motor speed profile, wherein the predefined motor speed profile defines a first ramping time period comprising a first stored duration, an ignition stage time period comprising a second stored duration, a first motor speed for the ignition stage time period, a second ramping time period comprising a third stored duration, and a second motor speed for a combustion stage, and wherein a value of the first motor speed is determined based on a size of the furnace;
a communication interface operable to receive a signal from a system controller, the signal representing a command to operate the draft inducer motor; and
a processor operable to operate the draft inducer motor in accordance with the predefined motor speed profile during at least one of 1) the first ramping time period and the ignition stage time period, and 2) the second ramping time period and the combustion stage of the furnace.

2. The motor controller of claim 1 , wherein said communication interface comprises an input terminal configured to be coupled to a relay of the system controller, said input terminal operable to receive the signal from the system controller.

3. The motor controller of claim 2 , wherein said input terminal is operable to receive at least one of a discrete signal, a serial signal, a parallel signal, an analog signal, and a digital communication signal.

4. The motor controller of claim 1 , wherein said processor, in operating the draft inducer motor in accordance with the predefined motor speed profile, is further operable to:
ramp a speed of the draft inducer motor up to the first motor speed over a first ramping time period to cause the inducer blower to generate airflow through an inlet duct of the furnace;
maintain the speed of the draft inducer motor at the first motor speed for a second time period, the second time period representing the ignition stage time period, during the ignition stage of the furnace;
ramp a speed of the draft inducer motor up to the second motor speed over a third time period, the third time period representing the second ramping time period, upon completion of the second time period; and
maintain the speed of the draft inducer motor at the second motor speed upon completion of the third time period during the combustion stage of the furnace.

5. The motor controller of claim 4 , wherein the first motor speed is lower than a steady-state combustion speed, wherein the first motor speed is a speed at which the draft inducer motor operates to facilitate gas ignition in a burner compartment of the furnace.

6. A motor controller for a draft inducer motor that operates an inducer blower in a furnace, said motor controller comprising:
a memory configured to store a predefined motor speed profile, wherein the predefined motor speed profile defines a first ramping time period, an ignition stage time period, a first motor speed for the ignition stage time period, and a second ramping time period, and a second motor speed for a combustion stage, and wherein a value of the first motor speed is determined based on a size of the furnace;
a communication interface operable to receive a signal from a system controller, the signal representing a command to operate the draft inducer motor; and
a processor operable to operate the draft inducer motor in accordance with the predefined motor speed profile during at least one of 1) the first ramping time period and the ignition stage time period, and 2) the second ramping time period and the combustion stage of the furnace.

7. The motor controller of claim 6 , wherein the value of the first motor speed is within a range of 1,000-3,000 revolutions per minute (RPM).

8. The motor controller of claim 4 , wherein the second motor speed is a steady-state combustion speed that corresponds to an airflow at which the furnace is designed to operate.

9. The motor controller of claim 8 , wherein the value of the second motor speed is within a range of 4,000-6,000 RPM.

10. The motor controller of claim 1 , wherein said processor is further operable to power off the draft inducer motor when the signal is no longer received from the system controller.

11. The motor controller of claim 1 , wherein said communication interface comprises a wireless module configured to receive wireless programming signals from an external programming computer device.

12. The motor controller of claim 11 , wherein the wireless programming signals include the predefined motor speed profile.

13. The motor controller of claim 12 , wherein the predefined motor speed profile is programmed into the memory while the draft inducer motor is on an assembly line during manufacture or while the draft inducer motor is packaged for shipment.

14. The motor controller of claim 11 , wherein the wireless programming signals are at least one of Bluetooth signals, Bluetooth low energy signals, near field communications (NFC) signals, and infrared signals.

15. A method of controlling a draft inducer motor that operates an inducer blower in a furnace, said method comprising:
storing, in a memory, a predefined motor speed profile, wherein the predefined motor speed profile defines a first ramping time period comprising a first stored duration, an ignition stage time period comprising a second stored duration, a first motor speed for the ignition stage time period, a second ramping time period comprising a third stored duration, and a second motor speed for a combustion stage, and wherein a value of the first motor speed is determined based on a size of the furnace;
receiving, by a communication interface of a motor controller a signal from a system controller, the signal representing a command to operate the draft inducer motor; and
operating, by a processor of the motor controller, the draft inducer motor in accordance with the predefined motor speed profile during at least one of 1) the first ramping time period and the ignition stage time period, and 2) the second ramping time period and the combustion stage of the furnace.

16. The method of claim 15 , further comprising:
coupling an input terminal of the communication interface to a relay of the system controller; and
receiving, by the input terminal, the signal from the system controller, wherein the signal includes at least one of a discrete signal, a serial signal, a parallel signal, an analog signal, and a digital communication signal.

17. The method of claim 15 , wherein operating the draft inducer motor in accordance with the predefined motor speed profile, further comprises:
ramping, by the processor, a speed of the draft inducer motor up to the first motor speed over a first ramping time period to cause the inducer blower to generate airflow through an inlet duct of the furnace;
maintaining, by the processor, the speed of the draft inducer motor at the first motor speed for a second time period, the second time period representing the ignition stage time period, during the ignition stage of the furnace;
ramping, by the processor, a speed of the draft inducer motor up to the second motor speed over a third time period, the third time period representing the second ramping time period, upon completion of the second time period; and
maintaining, by the processor, the speed of the draft inducer motor at the second motor speed upon completion of the third time period during the combustion stage of the furnace.

18. A furnac

Assignees

• Regal Beloit America Inc

Inventors

• Scroggins Devan
• Mullin Paul Steven

Classifications

• F23N3/085 Primary

  using electrical or electromechanical means · CPC title

• F23N2237/02

  two or more burners · CPC title

• F23N2225/06

  for determining flow · CPC title

• F23N2241/02

  Space-heating · CPC title

• F23N2227/02

  Starting or ignition cycles · CPC title