Switching fuel rail for a diesel fuel engine

Patent metadata

Field	Value
Publication number	US-12085050-B2
Application number	US-202218049719-A
Country	US
Kind code	B2
Filing date	Oct 26, 2022
Priority date	Oct 26, 2022
Publication date	Sep 10, 2024
Grant date	Sep 10, 2024

Abstract

An internal combustion engine system is described herein. The system uses a switching rail in combination with a first fuel rail to operate the internal combustion engine of the system. The first fuel rail receives the first fuel for combustion within one or more of the combustion cylinders of the internal combustion engine. The switching rails are configured to receive either the first fuel or a second fuel. A controller is used to operate a switching valve that, depending on the position of the switching valve, routes or directs either the second fuel or the first fuel from their respective fuel tanks. In a switching condition, such as startup, shutdown, or when the second fuel is not available, the controller can use the first fuel as the alternate source of fuel provided through the switching rail.

First claim

What is claimed is:

1. An internal combustion engine comprising:
a plurality of combustion cylinders, each of the plurality of combustion cylinders having a pilot injector for injecting a first fuel, from a first fuel rail, directly into each of the plurality of combustion cylinders, and a primary injector for injecting a second fuel or the first fuel, from a switching rail, directly into each of the plurality of combustion cylinders,
a first fuel supply of the first fuel;
a second fuel supply of the second fuel, wherein the second fuel is ignitable in the plurality of combustion cylinders based on a compression-ignition of the first fuel;
the first fuel rail for providing the first fuel to the pilot injector of each of the plurality of combustion cylinders;
the switching rail configured to provide either the second fuel or the first fuel to the primary injector of each of the plurality of combustion cylinders; and
a switching valve selectable to receive and route the second fuel from a second fuel tank in a first position of the switching valve and selectable to receive and route the first fuel from a first fuel tank to primary feed lines of the switching rail in a second position of the switch valve, wherein in the first position the second fuel is provided to the switching rail rather than the first fuel, and wherein in the second position the first fuel is provided to the switching rail rather than the second fuel.

2. The internal combustion engine of claim 1 , wherein the first fuel comprises diesel and the second fuel comprises methanol.

3. The internal combustion engine of claim 1 , further comprising a controller configured to:
detect a switching condition of the internal combustion engine; and
transmit a switching signal to the switching valve to switch from an intake of the second fuel into the primary feed lines to an intake of the first fuel into the primary feed lines.

4. The internal combustion engine of claim 3 , wherein the controller is further configured to:
detect a switching condition of the internal combustion engine has cleared; and
transmit a switching signal to the switching valve to switch from an intake of the first fuel into the primary feed lines to an intake of the second fuel into the primary feed lines.

5. The internal combustion engine of claim 3 , wherein the switching condition comprises a startup of the internal combustion engine or a shutdown of the internal combustion engine.

6. The internal combustion engine of claim 3 , wherein the switching condition comprises a loss of an availability of the second fuel or a selection of the first fuel as the second fuel.

7. The internal combustion engine of claim 3 , wherein the controller is further configured to transmit one or more injector signals during the switching condition, wherein the switching signal instructs the pilot injector and the primary injector of each of the plurality of combustion cylinders to open and close at various times and lengths of time based on the switching condition.

8. The internal combustion engine of claim 3 , wherein the controller is further configured to:
detect a pressure of the switching rail;
determine that the pressure is above a setpoint; and
transmit a pressure control signal to a pressure valve to vent the switching rail.

9. The internal combustion engine of claim 1 , further comprising a return valve configurable to provide unused second fuel from the switching rail to the second fuel tank or the first fuel to the first fuel tank.

10. The internal combustion engine of claim 1 , further comprising a gas valve that, when opened provides an inert gas to the switching rail to force at least a portion of either the second fuel or the first fuel in the switching rail out of the switching rail.

11. A method of operating an internal combustion engine, comprising:
monitoring, by a controller, the internal combustion engine, wherein the internal combustion engine comprises a plurality of combustion cylinders, each of the plurality of combustion cylinders having a pilot injector for injecting a first fuel, from a first fuel rail, directly into each of the plurality of combustion cylinders, and a primary injector for injecting a second fuel or the first fuel, from a switching rail, directly into each of the plurality of combustion cylinders;
detecting, by the controller, a switching condition;
modifying, by the controller, the switching rail from receiving second fuel to receiving the first fuel rather than receiving the second fuel;
detecting, by the controller, that the switching condition has cleared; and
modifying, by the controller, the switching rail from receiving the first fuel to receiving the second fuel rather than receiving the first fuel.

12. The method of claim 11 , wherein the switching condition comprises a startup of the internal combustion engine, a shutdown of the internal combustion engine, or a loss of an availability of the second fuel.

13. The method of claim 11 , wherein the first fuel comprises diesel and the second fuel comprises methanol.

14. The method of claim 11 , wherein modifying, by the controller, a switching rail from receiving a second fuel to receiving a first fuel comprises transmitting, by the controller, a switching signal to a switching valve to switch from an intake of the second fuel into primary feed lines to an intake of the first fuel into the primary feed lines.

15. The method of claim 11 , wherein modifying, by the controller, the switching rail from receiving the first fuel to receiving the second fuel comprises transmitting a switching signal to a switching valve to switch from an intake of the first fuel into primary feed lines to an intake of the second fuel into the primary feed lines.

16. The method of claim 11 , further comprising:
detecting a pressure of the switching rail;
determining that the pressure is above a setpoint; and
transmitting a pressure control signal to a pressure valve to vent the switching rail.

17. A controller for controlling an internal combustion engine, the controller comprising:
a memory storing computer-executable instructions; and
a processor in communication with the memory, the computer-executable instructions causing the processor to perform acts comprising:
monitoring the internal combustion engine, wherein the internal combustion engine comprises a plurality of combustion cylinders, each of the plurality of combustion cylinders having a pilot injector for injecting a first fuel, from a first fuel rail, directly into each of the plurality of combustion cylinders, and a primary injector for injecting a second fuel or the first fuel, from a switching rail, directly into each of the plurality of combustion cylinders;
detecting a switching condition;
modifying the switching rail from receiving the second fuel to receiving the first fuel rather than receiving the second fuel;
detecting that the switching condition has cleared; and
modifying the switching rail from receiving the first fuel to receiving the second fuel rather than receiving the first fuel.

18. The controller of claim 17 , wherein the computer-executable instructions for modifying the switching rail from receiving the second fuel to receiving the first fuel comprises computer-executable instructions that, when executed by the processor, cause the processor to perform acts comprising transmitting a switching signal to a switching valve to switch from an intake of the second fuel into primary feed lines to an intake of the first fuel into the primary feed lines.

Assignees

• Caterpillar Inc

Inventors

• Kim Hoisan
• Kim Arnold Myoungjin
• Coldren Dana Ray
• Schroeder Eric Lee

Classifications

• F02D19/0613 Primary

  Switch-over from one fuel to another (F02D19/081 takes precedence) · CPC title

• F02D19/0694

  operating with a plurality of fuels · CPC title

• F02D41/0027

  the fuel being gaseous (non-electrical control F02D19/02) · CPC title

• F02D41/0025

  Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures · CPC title

• F02D19/0615

  being initiated by automatic means, e.g. based on engine or vehicle operating conditions · CPC title