Vehicle heater and controls therefor

Patent metadata

Field	Value
Publication number	US-11319916-B2
Application number	US-201716089320-A
Country	US
Kind code	B2
Filing date	Mar 30, 2017
Priority date	Mar 30, 2016
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

A heater comprises a combustion chamber and a jacket extending about the combustion chamber. There is a fan having an output which communicates with the combustion chamber to provide combustion air. There is also a fuel delivery system having a variable delivery rate. A burner assembly is connected to the combustion chamber. The burner assembly has a burner mounted thereon adjacent the combustion chamber. The burner receives fuel from the fuel delivery system. There is an exhaust system extending from the combustion chamber. An oxygen sensor is positioned in the exhaust system to detect oxygen content of exhaust gases. There is a control system operatively coupled to the oxygen sensor and the fuel delivery system. The control system controls the delivery rate of the fuel delivery system according to the oxygen content of the exhaust gases.

First claim

What is claimed is:

1. A burner comprising:
a nozzle having an outlet and a disparager assembly, wherein the disparager assembly includes an outer barrel having a threaded inner wall portion and an inner rod having a threaded outer wall portion, wherein the threaded inner wall portion of the outer barrel and the threaded outer wall portion of the inner rod have different thread pitches and define a tortuous flow path on an outer side of the threaded outer wall portion of the inner rod, wherein the outer side of the threaded outer wall portion of the inner rod faces the threaded inner wall portion of the outer barrel, wherein the tortuous flow path is between the threaded inner wall portion of the outer barrel and the threaded outer wall portion of the inner rod, and wherein the tortuous flow path is positioned to convey fuel to the outlet of the nozzle.

2. A heater for a liquid, the heater comprising:
a combustion chamber;
a jacket operable to receive the liquid, the jacket extending about the combustion chamber;
a blower assembly having an output communicating with the combustion chamber, the blower assembly operable to provide combustion air to the combustion chamber;
a fuel delivery system including a fuel pump; and
a burner assembly connected to the combustion chamber, the burner assembly having the burner of claim 1 mounted thereon adjacent the combustion chamber, the burner operable to receive the fuel from the fuel delivery system;
wherein the tortuous flow path is positioned to convey the fuel between the fuel delivery system and the outlet of the nozzle.

3. The heater as claimed in claim 2 , further including:
an exhaust system extending from the combustion chamber and operable to discharge, from the heater, exhaust gases produced by combustion in the combustion chamber;
an oxygen sensor positioned in the exhaust system and operable to detect oxygen content of the exhaust gases; and
a control system operatively coupled to the oxygen sensor, the blower assembly and the fuel delivery system, the control system operable to control at least:
a variable combustion air delivery rate of the combustion air from the blower assembly according to a desired heat output level of the heater and independently of the oxygen content of the exhaust gases, the desired heat output level selected from a plurality of different selectable heat output levels of the heater; and
a variable fuel delivery rate of the fuel delivery system according to the oxygen content of the exhaust gases.

4. The heater as claimed in claim 3 , wherein the control system is operable to provide a closed loop feedback control.

5. The heater as claimed in claim 3 , wherein the fuel delivery system includes a proportional control valve, the control system operable to control the fuel delivery rate of the fuel delivery system via the proportional control valve.

6. The heater as claimed in claim 3 , wherein the blower assembly comprises a blower and a blower motor operable to power the blower, and wherein the control system is operable to control at least a speed of the blower motor according to the desired output level of the heater and independently of the oxygen content of the exhaust gases.

7. The heater as claimed in claim 3 , further including:
an air compressor, the nozzle being an atomizing nozzle connected to the air compressor to receive compressed air therefrom and the nozzle being connected to the fuel delivery system to receive the fuel therefrom, the atomizing nozzle operable to utilize the compressed air received from the air compressor to deliver an atomized spray of the fuel into the combustion chamber;
wherein the control system is further operable to control at least a pressure of the compressed air from the air compressor according to the desired output level of the heater and independently of the fuel delivery rate.

8. The heater as claimed in claim 2 , further including an air compressor, the nozzle being an atomizing nozzle connected to the air compressor to receive compressed air therefrom and the nozzle being connected to the fuel delivery system to receive the fuel therefrom, the atomizing nozzle operable to utilize the compressed air received from the air compressor to deliver an atomized spray of the fuel into the combustion chamber.

9. The heater as claimed in claim 8 , wherein the air compressor has an electric drive motor operable to cause the air compressor to produce the compressed air in response to rotation of an output shaft of the electric drive motor, the output shaft of the electric drive motor being rotationally coupled to the fuel pump by a magnetic coupling operable to transfer a torque from the output shaft of the electric drive motor to the fuel pump to power the fuel pump in response to the rotation of the output shaft of the electric drive motor.

10. The heater as claimed in claim 9 , wherein the magnetic coupling includes:
a drive cup coupled to the output shaft of the electric drive motor of the air compressor for rotation in response to the rotation of the output shaft of the electric drive motor of the air compressor; and
a shaft follower within and magnetically coupled to the drive cup and connected to the fuel pump by a shaft such that the rotation of the output shaft of the electric drive motor powers the fuel pump.

11. The heater as claimed in claim 2 , wherein the combustion chamber has a wall with a plurality of apertures extending therethrough and communicating with the blower assembly to deliver the combustion air along the combustion chamber.

12. The heater as claimed in claim 11 , wherein the wall of the combustion chamber is a double wall, the double wall including a cylindrical inner wall portion, a cylindrical outer wall portion which extends about and is spaced-apart from the inner wall portion, and a space extending between the inner wall portion and the outer wall portion, the space being operatively connected to the blower assembly to receive the combustion air therefrom, the plurality of apertures extending through the inner wall portion.

13. The heater as claimed in claim 2 , further including an air swirler operable to cause the combustion air to swirl prior to entry into the combustion chamber.

14. The heater as claimed in claim 13 , wherein the air swirler has radially extending fins.

15. The heater as claimed in claim 13 , wherein the air swirler has axially extending fins.

16. The heater as claimed in claim 2 , wherein the combustion chamber has a first end and a second end, the heater further including:
a first set of spaced-apart fins extending from the combustion chamber to the jacket to promote heat transfer therebetween, the first set of spaced-apart fins comprising a plurality of axially and radially extending fins; and
a second set of spaced-apart fins extending from the combustion chamber to the jacket and from near the first end of the combustion chamber partway towards the second end of the combustion chamber, the second set of spaced-apart fins comprising a plurality of axially and radially extending fins, each of the fins of the second set of spaced-apart fins being disposed between two adjacent fins of the first set of fins.

17. The heater as claimed in claim 2 , further including a control system, wherein the jacket includes a first temperature sensor and a second temperature sensor, the control system operable to detect the presence or absence of a flame by comparing a temperature of the liquid at the first temperature sensor and a temperature of the liquid at the second temperature sensor.

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Assignees

• Marine Canada Acquisition Inc

Inventors

• Strang Kenneth
• Wilnechenko Bruce
• Thomas Korbin
• Strankman Daine

Classifications

• F23D11/10

  the spraying being induced by a gaseous medium, e.g. water vapour · CPC title

• F24H9/1836

  using fluid fuel · CPC title

• F01P2060/18

  Heater · CPC title

• F23N5/265

  using electronic means · CPC title

• F23N5/006

  the detector being sensitive to oxygen · CPC title