SELF-IGNITING GASEOUS FUEL INJECTOR FOR INTERNAL COMBUSTION ENGINE

INJECTEUR DE CARBURANT GAZEUX AUTO-INFLAMMABLE POUR MOTEUR A COMBUSTION INTERNE

English Abstract

A self-igniting gaseous fuel injector, comprising a fuel injector and a
radical
generator in this invention, injects a fuel to combustion chamber (cylinder)
of an internal
combustion engine at prescribed variable or non-variable pressure and
quantities and
predetermined timing intervals through single or multiple ports. The radical
generator
produces radicals/ions at predetermined timing and concentrations by breaking
the fuel
molecules before injection of the fuel into the cylinder and it reacts and
ignites itself with
the cylinder air or prescribed cylinder mixture as it enters into the cylinder
with or
without external igniting sources which can be located in an appropriate part
of the
cylinder. The radical generator can be electrical spark discharge type or
plasma reactor
type or electric-magnetic type (including micro-wave type) that is primarily
used to break
molecules of the fuel into radicals/ions at prescribed amounts and timing. The
fuel can be
gaseous fuels or liquid fuel vapors or mixtures of gaseous fuels or mixtures
of gaseous
fuels and liquid fuel vapors. The radical generator is positioned at
prescribed location
and in predetermined shape in the fuel injection system.
11

Claims

CLAIMS
1. A method of a fuel supply for an internal combustion engine, comprising the
steps of providing a source of a fluid fuel and radical/ion in predetermined
quantities and predetermined ways which are determined in correspondence
with sensed operational parameter of the internal combustion engine so as to
provide fuel and radical/ion mixture to be supplied to the internal combustion
engine.
2. A method as defined in claim 1; wherein said sensing of an operational
parameter includes a sensing selected from the group consisting of sensing an
engine coolant temperature, an intake air temperature, an engine speed, a
manifold pressure, a fuel pressure, a battery voltage, an exhaust gas oxygen
composition, a knocking, a mass air flow and an exhaust gas recirculation.
3. A method as defined in claim 1; and further comprising providing a fuel
metering means for the fuel located downstream of said source and a regulator
so as to provide the fuel at predetermined pressure.
4. A method as defined in claim 1; and further comprising a pressure boosting
pump and or evaporator if the fuel is supplied in liquid form.
5. A method as defined in claim 1; wherein said radical/ion are generated by
breaking the fuel molecules into various radical and or ion which are more
prompt to chemical reaction and provide ignition of the fuel and oxidant
mixture, and said radical/ion generator may be consist of a radical/ion
generator unit and a power supply unit.
6. A method as defined in claim 5; further comprising a system that provides a
necessary quantities at predetermined time of radical and or ion in order to
provide ignition of the fuel in the combustion chamber of the internal
combustion engine.
7. A method as defined in claim 5; wherein said radical/ion generator system
may be of various types such as a thermal or non thermal plasma type, a
microwave type and, a spark discharge type that are capable to provide
predetermined amount of such radical and or ion at predetermined time and
duration.
8. A method as defined in claim 1; and further comprising an injection nozzle
or
injector to provide the fuel and radical/ion mixture into the cylinder of the
engine at predetermined pressure and temperature and predetermined ways.
6

9. A method as defined in claim 1; and further comprising a provision to
supply
an additive in order to reduce the power requirement of and improve
efficiency of radical and or ion generator.
10. A method as defined in claim 1; and further comprising providing
assistance
from such as glow plug, or heat surface or spark igniter to ignite the fuel
and
radical/ion mixture in the combustion chamber in the internal combustion
engine.
11. A system of a fuel supply for an internal combustion engine, comprising
the
steps of providing a source of a fluid fuel and radical/ion in predetermined
quantities and predetermined ways which are determined in correspondence
with sensed operational parameter of the internal combustion engine so as to
provide fuel and radical/ion mixture to be supplied to the internal combustion
engine.
12. A system as defined in claim 11; wherein said sensing of an operational
parameter includes a sensing selected from the group consisting of sensing an
engine coolant temperature, an intake air temperature, an engine speed, a
manifold pressure, a fuel pressure, a battery voltage, an exhaust gas oxygen
composition, a knocking, a mass air flow and an exhaust gas recirculation.
13. A system as defined in claim 11; and further comprising providing a fuel
metering means for the fuel located downstream of said source and a regulator
so as to provide the fuel at predetermined pressure.
14. A system as defined in claim 11; and further comprising a pressure
boosting
pump and or evaporator if the fuel is supplied in liquid form.
15. A system as defined in claim 11; wherein said radical/ion are generated by
breaking the fuel molecules into various radical and or ion which are more
prompt to chemical reaction and provide ignition of the fuel and oxidant
mixture, and said radical/ion generator may be consist of a radical/ion
generator unit and a power supply unit.
16. A system as defined in claim 15; further comprising a system that provides
a
necessary quantities at predetermined time of radical and or ion in order to
provide ignition of the fuel in the combustion chamber of the internal
combustion engine.
17. A system as defined in claim 15; wherein said radical/ion generator system
may be of various types such as a thermal or non thermal plasma type, a
microwave type and, a spark discharge type that are capable to provide
predetermined amount of such radical and or ion at predetermined time and
duration.
7

18. A system as defined in claim 11; and further comprising an injection
nozzle
or injector to provide the fuel and radical/ion mixture into the cylinder of
the
engine at predetermined pressure and temperature and predetermined ways.
19. A system as defined in claim 11; and further comprising a provision to
supply
an additive in order to reduce the power requirement of and improve
efficiency of radical and or ion generator.
20. A system as defined in claim 11; and further comprising providing
assistance
from such as glow plug, or heat surface or spark igniter to ignite the fuel
and
radical/ion mixture in the combustion chamber in the internal combustion
engine.
8

Description

CA 02307927 2001-08-13
Title of'Invention: Self igniting gaseous fuel injector for internal
combustion engine
Inventor: Shiva Om Bade Shrestha
#12, 8_540 Silver Spring Road N. W.
Calgary, AB, T3B 4J6
Canada
Phone: 403 - 2$9 3724
Email:sobadeshrestha(aOhotmail.com
Description of the Invention
Field of~the invention:
This invention relates to fuel injector for internal combustion engines for
delivering particularly gaseous fuel to an engine.
Background of the invention:
Fuel injection system is used to deliver fuel to internal combustion engines.
Majority of injection systems is designed to deliver liquid conventional fuels
such as
gasoline and diesel fuels. Engines that runs in alternative fuels such as
natural gas and
propane have been also developed. Majority of these alternative fuel engines
is spark
ignition type or dual fuel engine type that runs on diesel and a gaseous fuel
such as
propane or natural gas. Generally, in dual fuel engines, diesel fuel is used
as a pilot
igniter for gaseous fuel mixture inside the engine cylinder. In these engines,
the gaseous
fuel is either injected through the same injector as of diesel or a separate
injector or a
injector that is located at intake manifold or intake valve. Conversion kits
have also been
developed for converting gasoline or diesel (liquid fuel) engines to natural
gas or propane
(gaseous fuel). Generally these conversion kits comprise a fuel/air mixer
system for
delivering the gaseous fuel to the engine cylinder.
Disclosure of the Invention:
The present invention of a new concept of fuel injectors that provides a self
igniting gaseous fuel at the predetermined pressure, ways and parts of
injection of a fuel
into an engine cylinder is disclosed. This avoids the necessity of injecting
diesel fuel to
provide pilot into a dual fuel engine which is a general case. Hence, there
will be no need
to have two separate fuel supply systems in these engines and the engine will
run just like
a diesel engine (compression ignition engine) only with gaseous fuel
injection.
The present invention of a self igmiting gaseous fuel injector is comprised of
a
fuel injector and a radical generator. The fuel injector injects a fuel to
combustion
chamber (cylinder) of an internal combustion engine at prescribed variable or
non-
variable pressure and quantities and predetermined timing intervals through
single or
multiple ports. The radical generator produces radicals at predetermined
timing and
concentrations by breaking the fuel molecules before injection of the fuel
into the

CA 02307927 2001-08-13
cylinder so that it can react and ignite itself with the cylinder air or
prescribed cylinder
mixture as it enters into the cylinder with or without external igniting
sources which can
be located in an appropriate part of the cylinder. 'the radical generator can
be electrical
spark discharge type or plasma reactor type or electric-ma~,n~etic type
(including micro-
wave type) that is primarily used to break molecules of the fuel into radicals
at prescribed
amounts and timing. The fuel can be gaseous fuels or liquid fuel vapors or
mixtures of
gaseous fuels or mixtures of gaseous fuels and liquid fuel vapors. The radical
generator is
positioned at prescribed location and in predetermined shape in the fuel
injection system.
2

CA 02307927 2001-08-13
BRIEF DESCRIPTION OF THE DRA WINGS
Figure 1 is a view schematically showing a specific system for fuel supply
of an internal combustion engine in accordance with the present invention,
which
operates with the use of an inventive method; and
Figure 2 is a view schematically showing a basic system for fuel supply of
an internal combustion engine in accordance with the present invention which
operates
with the use of an inventive method.
3

CA 02307927 2001-08-13
DISCRIPTION OF PREFFERED EMBODIMENTS
A fuel supply system in accordance with the present invention which operates
in
accordance with the inventive method is used for supplying fuel to an internal
combustion engine, for example a compression ignition or a dual fuel engine 9.
The
system includes a high pressure fuel tank 1 for storing fluid fuel such as
natural gas or
hydrogen or propane or any gaseous fuel. A control valve or similar device 3
controls
supply of the fuel from the gas tank 1 to the internal combustion engine. The
engine is
provided with intake manifold system 7 with throttle 7 (optional) and an
exhaust system
10. In the case of modern closed loop engine, the exhaust system 10 includes
an exhaust
gas oxygen sensor which outputs an information about oxygen content in the
exhaust
gases on a signal line. Although it is illustrated as a closed-loop control
system, the
electronic control unit 6 in accordance with the present invention can be used
to operate
with engines which are opened-looped and do not have an exhaust gas oxygen
sensor.
The engine in accordance with the present invention is equipped with fuel
injection system which includes a radical/ion generator 4 and a injector or a
nozzle 5.
However, the preferred embodiment is described with a direct-in-cylinder
injection
system it may equally be suited to operate with a carbureted or an intake
manifold
inj ection.
The electronic unit 6 accepts inputs from several sensors including from
operator
accelerator paddle 1 I and it outputs control signals to valve 3 and or
injector 5 which can
be formed as normally closed fuel-gas control solenoid valve. It also outputs
control
signals to the radical and or ion generator control module 4. In principle,
the radical and
or ion generator and the injector may incorporated in one unit. During the
operation the
electronic control unit may receive signals from an engine coolant temperature
sensor, an
intake air temperature sensor, an engine speed sensor, a throttle position
sensor
(optional), a manifold pressure sensor, a fuel pressure sensor, an accelerator
pedal sensor
and a battery voltage sensor. For optimal perfornlance it is preferable that
the electronic
control unit also receives input from one or several other sensors such as
exhaust gas
oxygen sensor, a mass air flow sensor, a barometric sensor, and an exhaust gas
recirculation sensor if the engine has exhaust recirculation capabilities.
Also other sensors
can be used for sensing other operating parameters.
As shown in Figure 1, the electronic control unit receives a number of signals
from sensors which monitor selected operating conditions the engine 9, and in
turn sends
a signal to the control valves 3 and a signal to radical/ion generator 4 and
or injector or
nozzle if needed which supply the compressed high pressure gaseous fuel to the
cylinder.
A pressure regular 2 may be used to supply the fuel at predetermined pressure.
As the
fuel is supplied at or near top dead center, a high pressure fuel system is
needed. In case,
if fuel pressure available in the tank is not enough, a pressuring system may
be included.
If liquified gaseous fuel is supplied a liquid pressure pump and evaporator
may be
incorporated. The output signal from the electronic control unit 6 to the
valve 3 and
radical/ion generator and or injector may be a pulse-width modulation signal
over a fuel
4

CA 02307927 2001-08-13
injection fuel line to control the injection of the fuel. However other types
of control
methods and other forms of fuel delivery may be utilized.
The duration of opening and the time of opening for the control valve 3 and or
radical/ion generator 4 and or injector 5 are determined by a series of
computations
performed by the electronic control unit 6, using as inputs the signals
delivered by the
various sensors described above. The activation of the radical/ion generator
allows to
break down the molecule of fuel into many types of radicals and ion particles
that ignites
as it enters into the engine cylinder and helps ignite the fuel injected. This
provides the
uniqueness of this invention that no spark ignition system is needed and the
fuel can be
ignited as diesel fuel in compression ignition type engines. For an example,
this avoids
the use of diesel pilot in dual fuel engines and these engines can be run on
the gaseous
fuel just as diesel engines. The radical/ion generator may consist of a power
supply unit
and a radical/ion producer such as a plasma generator, a micro-wave-producer
and or a
powerful spark discharge. T'o reduce the power requirement and improve the
effectiveness of radical/ion generator an additive may be used in the fuel
supply system.
While the invention has been illustrated and described as embodied in method
of
and system for fuel supply for an internal combustion engine, it is not
intended to be
limited to the details shown, since various modifications and structural
changes may be
made without departing in any way from the spirit of the present invention.
Without further analysis, the following will so fully reveal the gist of the
present
invention that others can, by applying current knowledge, readily adapt it for
various
applications without omitting features that, from the standpoint of prior art,
fairly
constitute essential characteristics of the generic or specific aspects of
this invention.
What is claimed as new and desired to be protected by Letters of Patent is set
forth in the appended claims.