Internal combustion engine
An internal combustion engine includes a pre-chamber. In another aspect, pressure within a pre-chamber is equal to or greater than pressure within a main combustion chamber at least prior to ignition in the main combustion chamber. In yet another aspect, internal combustion engine control software automatically controls pressure within a turbulent jet ignition pre-chamber, controls a valve-actuator to admit a fuel-air charge into the pre-chamber, and causes an igniter to initiate combustion in the pressurized pre-chamber. This also permits the rate of combustion to be controlled in the primary chamber regardless of the air-fuel ratio or the diluent fraction in the main chamber. Another aspect employs a pre-chamber purge pump with separate air and fuel injection.
1. An internal combustion engine comprising:
a pre-chamber including multiple apertures which are always open between the pre-chamber and main combustion chamber;
a main combustion chamber connected to the pre-chamber via the apertures;
an igniter operably releasing energy in the pre-chamber;
at least one injector having an outlet connected to the pre-chamber, the at least one injector supplying fuel separately from air, in an unmixed state, into the pre-chamber;
the air being injected into the pre-chamber prior to injection of the fuel to purge the pre-chamber of any prior combustion particles;
a first mixture of the air and the fuel combusting in the pre-chamber which thereafter ignites a second fuel air mixture in the main combustion chamber through the apertures; and
the pre-chamber having an internal pressure equal to or greater than that of the main combustion chamber at least prior to ignition in the main combustion chamber;
a first cam causing an air valve to move for an air purge pump; and
a second cam causing a supplemental piston to move fresh air from the purge pump into the pre-chamber.
2. The engine of claim 1 , wherein:
the igniter is at least partially located in the pre-chamber; and
an internal hollow volume of the purge pump is at least twice an internal hollow volume of the pre-chamber.
3. The engine of claim 2 , further comprising:
a main driving piston linearly moveable within the main combustion chamber and being connected to a crank shaft;
timing of at least the air valve associated with air flow from the purge pump being controlled by movement of the crank shaft.
4. The engine of claim 1 , further comprising springs being coaxially aligned with an elongated centerline axis of the purge pump.
5. The engine of claim 1 , wherein the purge pump and the pre-chamber are linearly located between the cams and the main combustion chamber.
6. The engine of claim 1 , wherein the pre-chamber has a constant volume.
7. The engine of claim 1 , further comprising pressure sensors associated with the pre-chamber and main combustion chamber operably sending signals to an electronic controller which uses the signals to automatically control the pressure and combustion timing of a subsequent cycle in the pre-chamber, and to automatically control timing of injection of the air separately from injection of the fuel into the pre-chamber.
8. The engine of claim 1 , further comprising oil acting on a valve to control valve opening of the purge pump, and a spring biasing a portion of the purge pump.
9. A method of operating an internal combustion engine in an automotive vehicle, the method comprising:
(a) pressurizing a constant volume pre-chamber, with a source external to a main piston chamber, to at least that of the main piston chamber connected therewith by multiple apertures which are always open;
(b) supplying a fuel into the pre-chamber through a fuel port;
(c) moving a valve of a purge pump due to rotation of a cam;
(d) supplying air to the purge pump and supplying air from the purge pump into the pre-chamber through an air port separate from the fuel port and at least partially prior to step (b);
(e) creating ignition energy in the pre-chamber to ignite the fuel and air in the pre-chamber;
(f) supplying fuel and air into the main piston chamber;
(g) moving combusted material from the pre-chamber through at least one of the apertures;
(h) moving a supplemental piston in the purge pump due to rotation of another cam;
(i) igniting the fuel and air in the main piston chamber with reacting mixture flowing through the apertures of the pre-chamber; and
(j) linearly moving an entire main driving piston away from the pre-chamber, within the main piston chamber.
10. The method of claim 9 , further comprising oil acting on the valve to control valve opening of the purge pump, and a spring biasing a portion of the purge pump.
11. The method of claim 9 , further comprising essentially completely combusting the fuel and air which is a 1.0 (a) or leaner fuel-air mixture in the main piston chamber.
12. The method of claim 9 , further comprising:
sensing pressure in the main piston chamber; and
automatically changing at least one of: a fuel-air ratio in the pre-chamber, a quantity of the fuel and air in the pre-chamber, ignition timing in the pre-chamber, injection timing of the air versus the fuel in the pre-chamber, or pressure in the pre-chamber.
13. The method of claim 9 , further comprising:
sensing ionization in the main piston chamber; and
automatically changing at least one of: a fuel-air ratio in the pre-chamber, a quantity of the fuel and air in the pre-chamber, ignition timing in the pre-chamber, injection timing of the air versus the fuel in the pre-chamber, or pressure in the pre-chamber.