Carbon monoxide detecting system for internal combustion engine-based machines

Patent metadata

Field	Value
Publication number	US-11905894-B2
Application number	US-202217572428-A
Country	US
Kind code	B2
Filing date	Jan 10, 2022
Priority date	Mar 31, 2017
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

An internal combustion engine-based system includes an internal combustion engine. The internal combustion engine-based system includes an engine interrupt connected to the engine. The engine interrupt is configured to selectively stop the operation of the engine. The internal combustion engine-based system includes a controller in communication with the engine interrupt. The internal combustion engine-based system includes a carbon monoxide detector in communication with the controller. The controller uses the engine interrupt to stop the operation of the engine when the carbon monoxide detector provides the controller with signals that are representative of a carbon monoxide level proximate the internal combustion engine that together form a trend of building carbon monoxide amounts over a set time interval.

First claim

What is claimed is:

1. A portable generator comprising:
an internal combustion engine that generates mechanical power;
a chassis assembly supporting the internal combustion engine and having a handle for transporting the portable generator;
an alternator that receives the mechanical power from the internal combustion engine and transforms at least a majority of the mechanical power into electrical energy;
an output interface that provides the electrical energy to an external device for powering the external device;
an engine interrupt connected to the internal combustion engine, wherein the engine interrupt is configured to selectively stop the operation of the internal combustion engine;
a controller in communication with the internal combustion engine and the engine interrupt; and
a carbon monoxide detector in communication with the controller, wherein the carbon monoxide detector provides the controller with signals that are representative of a carbon monoxide level proximate the internal combustion engine;
wherein the controller uses the engine interrupt to stop the operation of the engine under one of at least two shut down conditions, both of which are evaluated by the controller, including:
a first shutdown condition in which the controller identifies a magnitude value of the signals over a set time interval, and in which the magnitude value exceeds a predetermined shutoff threshold value; and
a second shutdown condition in which the controller calculates, for signal values exceeding a minimum noise threshold, a trend line having a rate of change value over a set time interval, and in which the rate of change value is one or both of a positive value or a value that exceeds a predetermined rate of change threshold value.

2. The portable generator of claim 1 , wherein the rate of change is a slope or an acceleration of the trend line.

3. The portable generator of claim 1 , wherein the magnitude value corresponds to a mean, median, or mode of the signals received over the second time interval.

4. The portable generator of claim 1 , wherein the first shutdown condition includes a plurality of sequentially evaluated magnitude values over a plurality of corresponding time intervals.

5. The portable generator of claim 4 , wherein the first shutdown condition includes:
a first magnitude threshold value evaluated over a first set time interval; and
a second magnitude threshold value evaluated over a second set time interval.

6. The portable generator of claim 5 , wherein the first magnitude threshold value is between 650 and 750 parts per million and the first set time interval is between 0 and 45 seconds, and wherein the second magnitude threshold value is between 300 and 400 parts per million and the second set time interval is between 5 and 15 minutes.

7. The portable generator of claim 1 , wherein the second shutdown condition includes a plurality of sequentially evaluated rate of change values over a plurality of corresponding time intervals.

8. The portable generator of claim 7 , wherein the second shutdown condition includes:
a first rate of change threshold value evaluated over a first set time interval; and
a second rate of change threshold value evaluated over a second set time interval.

9. The portable generator of claim 8 , wherein the first rate of change threshold value is between 5 and 15 parts per million per second squared and the first set time interval is between 0 and 1 second, and wherein the second magnitude threshold value is between 0.5 and 1.5 parts per million per second squared and the second set time interval is between 15 and 45 seconds.

10. The portable generator of claim 1 , wherein the controller monitors carbon monoxide levels and uses a regression analysis to determine the trend line of monitored carbon monoxide levels, and wherein a signal is sent to the engine interrupt by the controller when the slope of a regression line computed by the regression analysis is positive over the set time interval.

11. The portable generator of claim 1 , wherein the first set time interval is between about 15 seconds and about 60 minutes.

12. The portable generator of claim 1 , wherein the controller is a PID controller.

13. The portable generator of claim 1 , wherein the carbon monoxide detector automatically ceases the operation of the internal combustion engine when communication between the carbon monoxide detector and the controller is interrupted.

14. The portable generator of claim 1 , further comprising a secondary sensor in communication with the controller, wherein the secondary sensor is at least one of a carbon monoxide sensor, a temperature sensor, a humidity sensor, a proximity sensor, an accelerometer, and a timer.

15. The portable generator of claim 1 , wherein the controller alters or both of the minimum noise threshold and the predetermined slope threshold that indicates the trend of building carbon monoxide amounts over the set time interval based on historic signals received from the carbon monoxide detector.

16. The portable generator of claim 1 , wherein the carbon monoxide detector is integrated with the internal combustion engine so that, if the carbon monoxide detector is tampered with, the internal combustion engine ceases to operate.

17. A method of operating an internal combustion engine-based system of a portable generator, the method comprising:
detecting a carbon monoxide level proximate an internal combustion engine using a carbon monoxide detector;
activating a shutdown action under one of at least two shut down conditions, both of which are evaluated by a controller, including:
a first shutdown condition in which a magnitude value of detected carbon monoxide signals, over a set time interval, exceeds a predetermined shutoff threshold value; and
a second shutdown condition in which, for signal values exceeding a minimum noise threshold, a rate of change value determined from the detected carbon monoxide signals, over a set time interval, is one or both of a positive value or a value that exceeds a first predetermined rate of change threshold value.

18. The method of claim 17 , wherein the rate of change threshold value of the carbon monoxide level is an acceleration of the carbon monoxide level.

19. The portable generator of claim 17 , wherein the second shutdown condition includes:
a first rate of change threshold value evaluated over a first set time interval; and
a second rate of change threshold value evaluated over a second set time interval.

20. The method of claim 19 , wherein the first rate of change threshold value is between 5 and 15 parts per million per second squared and the first set time interval is between 0 and 1 second, and wherein the second magnitude threshold value is between 0.5 and 1.5 parts per million per second squared and the second set time interval is between 15 and 45 seconds.

21. The method of claim 17 , further comprising activating at least one of a visual and audio alarm when the at least one predetermined shutoff threshold or the predetermined rate of change threshold value is exceeded.

22. The method of claim 17 , further comprising determining whether the at least one predetermined shutoff threshold or the predetermined rate of change threshold value is exceeded by additionally using signals received from an additional sensor.

23. The method of claim 17 , further comprising determining whether the at least one predetermined shutoff threshold or the pre

Assignees

• Generac Power Systems Inc

Inventors

• Wischstadt Gregory A
• Schroeder Adam M
• Horn Mitchell L
• Schmidt Brandon
• Cole Kevin
• Tesch Tod R

Classifications

• F02D17/04 Primary

  rendering engines inoperative or idling, e.g. caused by abnormal conditions (dependent on lubricating conditions F01M1/22; dependent on cooling F01P5/14) · CPC title

• F02B63/048

  Portable engine-generator combinations · CPC title

• F02B77/086

  Sensor arrangements in the exhaust, e.g. for temperature, misfire, air/fuel ratio, oxygen sensors · CPC title

• F02D41/042 Primary

  for stopping the engine · CPC title

• F02D41/1453

  the characteristics being a CO content or concentration · CPC title