Internal combustion engine and a process for its operation

Claim 2

In a reciprocating internal combustion engine having for each cylinder an inlet valve, single induction channel means from atmosphere to the inlet valve for fuel and air delivery to the cylinder, a spark plug, and a unitary combustion chamber, an improvement which comprises: a. means for injecting fuel into the induction channel means at a preselected location to form a coherent combustible cloud in a formation zone therein during the periods of time that the inlet valve is closed, the amount of fuel injected by the injection means effecting an air-to-fuel ratio in the combustion chamber determined on the basis of a homogeneous charge that just prior to the occurrence of spark is too lean to burn; b. the induction channel means providing a space for a cloud free zone for air between the zone of cloud formation and the spark plug such that upon opening of the inlet valve the cloud will be inducted into the combustion chamber serially with air ahead of it for presence of the cloud at the spark plug when spark occurs and presence of the previously inducted air in a fuel-lean zone in the combustion chamber outside the cloud when spark occurs; and c. the induction channel means and the combustion chamber having a configuration to avoid substantial dissipation of the cloud during the time of the cloud's formation and induction into the combustion chamber to the spark plug until spark occurs so that the combustion chamber just prior to the occurrence of spark has a heterogeneous makeup of fuel and air with the cloud being fuel-rich relative to stoichiometric and the gases in the fuel-lean zone being fuel lean.

Claim 3

The improvement claimed in claim 1 wherein the injection means includes means for varying the amount of injected fuel in the cloud, whereby the fuel-to-air ratio is varied and the power of the engine is varied.

Claim 4

In a four-cycle internal combustion engine having at least one cylinder, a piston disposed for reciprocation in the cylinder, a unitary combustion chamber defined by the top of the piston and the cylinder when the piston is at approximately its uppermost position therein, a spark plug for initiating combustion in the combustion chamber, an inlet valve for admitting fuel and air into the combustion chamber, and an exhaust valve for exhausting products of combustion from the combustion chamber, an improvement for each cylinder which comprises: a. induction channel means serially communicating atmosphere with the combustion chamber through the inlet valve for supplying the cylinder with fuel and air; b. means for injecting fuel into the induction channel means in a zone upstream from the inlet valve during the time between inlet valve openings to develop a fuel-rich combustible cloud in the induction channel means, the injection means injecting an amount of fuel which effects an air-to-fuel ratio in the combustion chamber determined on the basis of a homogeneous charge and just prior to the occurrence of spark which is too lean to burn; c. a space in the induction channel means between the zone where the fuel-rich cloud is formed and the spark plug forming a cloud free zone without combustible gases and for assuming presence of the fuel-rich cloud at the spark plug at spark; d. the induction channel means and the cylinder having a configuration to avoid substantial dissipation of the cloud during the formation and subsequent induction of the cloud into the combustion chamber and during the time that the cloud is in the combustion chamber at least until spark occurs so that just prior to the occurrence of spark a heterogeneous charge is in the combustion chamber defined, relative to stoichiometric, by a fuel-rich cloud and a fuel lean zone of gases outside the cloud, the injection means effecting the injection of an amount of fuel which gives an overall fuel-to-air ratio on the combustion chamber that would be too lean to burn; and e. means for varying the power of the engine without throttling intake air.

Claim 5

In a four-cycle internal combustion engine having at least one cylinder, a piston disposed for reciprocation in the cylinder, a unitary combustion chamber defined by the top of the piston and the cylinder when the piston is at approximately its uppermost position therein, a spark plug for initiating combustion in the combustion chamber, an inlet valve for admitting fuel and air into the combustion chamber, and an exhaust valve for exhausting products of combustion from the combustion chamber, an improvement for each cylinder which comprises: a. induction channel means serially communicating atmosphere with the combustion chamber through the inlet valve for supplying the cylinder with fuel and air; b. means for injecting fuel into the induction channel means in a zone upstream from the inlet valve during the time between inlet valve openings to develop a fuel-rich combustible cloud in the induction channel means, the injection means injecting an amount of fuel which effects an air-to-fuel ratio in the combustion chamber determined on the basis of a homogeneous charge and just prior to the occurrence of spark which is too lean to burn; c. a space in the induction channel means between the zone where the fuel-rich cloud is formed and the spark plug forming a cloud free zone without combustible gases and for assuming presence of the fuel-rich cloud at the spark plug at spark; d. the induction channel means and the cylinder having a configuration to avoid substantial dissipation of the cloud during the formation and subsequent induction of the cloud into the combustion chamber and during the time that the cloud is in the combustion chamber at least until spark occurs so that just prior to the occurrence of spark a heterogeneous charge is in the combustion chamber defined, relative to stoichiometric, by a fuel-rich cloud and a fuel lean zone of gases outside the cloud, the injection means effecting the injection of an amount of fuel which gives an overall fuel-to-air ratio on the combustion chamber that would be too lean to burn; and e. means for varying the power of the engine without throttling intake air.

Claim 6

The improvement claimed in claim 3 wherein the power varying means includes: means for reducing the amount of fuel in the cloud to reduce fuel-to-air ratio of the engine.

Claim 7

The improvement claimed in claim 4 wherein the power varying means includes means for recirculating exhaust gases into the combustion chamber through the induction channel means, the recirculating means including an injector for injecting exhaust gas into the induction channel means during the time that the inlet valve is closed and forming a cloud of exhaust gases at a location for induction into the combustion chamber into a preselected position therein at spark.

Claim 8

The improvement claimed in claim 5 wherein the power varying means includes means for varying the point in time at which spark occurs during a cycle.

Claim 9

The improvement claimed in claim 3 wherein the means for varying the power includes: means for varying the amount of fuel injected into the induction channel means between a predetermined minimum and a predetermined maximum, the predetermined minimum being at a power output of the engine above no load operation; and means for retarding the spark of the engine for power outputs of the engine below that produced at the predetermined minimum.

Claim 10

In a four-cycle, spark ignition, reciprocating internal combustion engine having at least one cylinder, a piston disposed for reciprocation in the cylinder, an inlet and an exhaust valve for the cylinder, a unitary combustion chamber in the cylinder, and a spark plug for igniting a charge of fuel and air in the combustion chamber, an improvement in the induction system for each cylinder which comprises: a. induction pipe means serially communicating atmosphere with the combustion chamber through the inlet valve; b. means for injecting fuel into the induction pipe in a fuel injection zone during the time that the inlet valve is closed to form a combustible cloud in the zone, the induction pipe means providing a space for a cloud free zone for air between the zone of cloud formation and the spark plug; c. the space between the fuel injection zone and the spark plug being such that the cloud will be inducted into the cylinder with air serially ahead of it during the time that the inlet valve is open and be at the spark plug when spark occurs; d. the induction pipe means and the cylinder preventing substantial dissipation of the cloud during the cloud's formation, induction into the cylinder and arrival at the spark plug when spark occurs; e. means for varying the fuel-to-air ratio between a predetermined richness and a predetermined leanness by varying the quantity of fuel injected into the induction pipe means, the predetermined lean fuel-to-air ratio corresponding to a power output above no load operation; and f. means for retarding the spark for power outputs between no load and the power output corresponding to the predetermined lean fuel-to-air ratio.

Claim 11

In a four-cycle, spark ignition, reciprocating internal combustion engine having at least one cylinder, a piston disposed for reciprocation in the cylinder, an inlet and an exhaust valve for the cylinder, a unitary combustion chamber in the cylinder, and a spark plug for igniting a charge of fuel and air in the combustion chamber, an improvement in the induction system for each cylinder which comprises: a. induction pipe means serially communicating atmosphere with the combustion chamber through the inlet valve; b. means for injecting fuel into the induction pipe in a fuel injection zone during the time that the inlet valve is closed to form a combustible cloud in the zone, the induction pipe means providing a space for a cloud free zone for air between the zone of cloud formation and the spark plug; c. the space between the fuel injection zone and the spark plug being such that the cloud will be inducted into the cylinder with air serially ahead of it during the time that the inlet valve is open and be at the spark plug when spark occurs; d. the induction pipe means and the cylinder preventing substantial dissipation of the cloud during the cloud's formation, induction into the cylinder and arrival at the spark plug when spark occurs; e. means for varying the fuel-to-air ratio between a predetermined richness and a predetermined leanness by varying the quantity of fuel injected into the induction pipe means, the predetermined lean fuel-to-air ratio corresponding to a power output above no load operation; and f. means for retarding the spark for power outputs between no load and the power output corresponding to the predetermined lean fuel-to-air ratio.

Claim 14

The method claimed in claim 9 including the steps of: a. forming a cloud of relatively inert substance in the induction channel of each cylinder separate from the cloud of fuel and upstream from the inlet valve during the periods of time between openings of the inlet valve; and b. inducting the cloud of inert substance into the combustion chamber during the induction step; whereby the location of the two clouds in the cylinder is determined by their relative positions initially along the induction channel.

Claim 15

The method claimed in claim 9 including the step of varying the power of the engine by changing the amount of fuel in the cloud and thereby the fuel-to-air ratio.

Claim 16

The method claimed in claim 11 wherein the inducted air is not throttled.

Claim 17

The method claimed in claim 11 wherein the power varying step includes changing the time at which spark occurs.

Claim 18

The method claimed in claim 13 including the steps of: a. forming a cloud of relatively inert substance in the induction channel of each cylinder separate from the cloud of fuel upstream from the inlet valve during the time between inlet valve openings; and b. inducting the cloud of inert substance into the cylinder during the induction step.

Claim 19

The method claimed in claim 14 wherein the inducted air is not throttled.