Device for reducing the emission of pollution responsible products by external carburation engines during the deceleration periods

Claim 3

A device according to claim 1, wherein are provided in combination means switching off the ignition in said cylinder during the deceleration periods.

Claim 4

A device according to claim 1, wherein said duct admitting non-carburetted air opens in the inlet pipe of said cylinder at such a point thereOf that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is smaller than one third of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 5

A device according to claim 1, wherein said duct admitting non-carburetted air opens in the inlet pipe of said cylinder in close vicinity to said means for intermittent closure.

Claim 6

A device according to claim 1, wherein is provided means for simultaneously controlling the cutting off of the idling fuel supply circuit and the opening of said duct admitting non-carburetted air, during the deceleration periods, and vice-versa apart from the deceleration periods.

Claim 7

A device according to claim 5, wherein said means for simultaneous control consists of a two-position electrovalve connected to means for detecting the deceleration periods.

Claim 8

A device according to claim 1, wherein said means for completely suppressing during the deceleration periods the flow of carburetted air feeding said cylinder includes a throttle valve controlling said flow, adapted to completely obturate said inlet pipe of said cylinder during the deceleration periods and a device obturating said fuel supply circuit which provides for the idling operation of said engine.

Claim 9

An external carburation engine, including carburation means supplied with air and fuel, said carburation means opening into at least one cylinder through an inlet pipe provided with at least one device for intermittent closure and comprising an idling fuel supply circuit, and comprising in combination a throttle valve controlling the flow rate of carburetted air through said inlet pipe, and having a position of complete obturation of said inlet pipe during the idling and deceleration periods of the engine, a conduit supplying a carburetted mixture to the engine at idling speed, said conduit opening into said inlet pipe downstream of said throttle valve with respect to the direction of flow of the gases through said inlet pipe, and including means for cutting off the flow of carburetted mixture through said conduit exclusively during the deceleration periods of the engine, and means for admitting non-carburetted air into said cylinder during the deceleration periods through an additional duct opening in said inlet pipe downstream of said throttle valve with respect to the air flow through said inlet pipe, wherein said duct admitting non-carburetted air opens into said inlet pipe at such a point that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is at most equal to one half of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 10

An external carburation engine, including carburation means supplied with air and fuel, said carburation means opening into at least one cylinder through an inlet pipe provided with at least one device for intermittent closure and comprising an idling fuel supply circuit, and comprising in combination a throttle valve controlling the flow rate of carburetted air through said inlet pipe, and having a position of complete obturation of said inlet pipe during the idling and deceleration periods of the engine, a conduit supplying a carburetted mixture to the engine at idling speed, said conduit opening into said inlet pipe downstream of said throttle valve with respect to the direction of flow of the gases through said inlet pipe, and including means for cutting off the flow of carburetted mixture through said conduit exclusively during the deceleration periods of the engine, and means for admitting non-carburetted air into said cylinder during the deceleration periods through an additional duct opening in said inlet pipe downstream of said throttle valve with respect to the air flow through said inlet pipe, wherein said duct admitting non-carburetted air opens into said inlet pipe at such a point that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is at most equal to one half of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 11

An engine according to claim 8, wherein said means for simultaneous control consists of a two-position electrovalve connected to means for detecting the deceleration periods.

Claim 12

An engine according to claim 8, wherein said means for completely suppressing during the deceleration periods the flow of carburetted air feeding said cylinder includes a throttle valve controlling said flow, adapted to completely obturate said inlet pipe of said cylinder during the deceleration periods and a device obturating said fuel supply circuit which provides for the idling operation of said engine.

Claim 13

An engine according to claim 8, including a circuit for the idling operation of the engine and for the transition between the idling and the normal operation of the engine, wherein are provided means for successively effecting during the deceleration periods the closing of the throttle valve and that of said idling and transition circuit and effecting conversely the opening of said idling and transition circuit prior to that of said throttle valve during a return to the normal operating conditions of the engine, after a deceleration.

Claim 14

An engine according to claim 8, wherein are provided in combination means interrupting the ignition during the deceleration periods.

Claim 15

A process for reducing the emission of pollution responsible products from the external carburation engines during the deceleration periods, applicable to the engines having at least one inlet pipe for carburetted mixture connected to carburation means and including a throttle valve, said pipe opening out in at least one cylinder through an inlet orifice provided with means for intermittent closure, this engine including an idling fuel circuit, wherein are performed substantially simultaneously the following operations during the deceleration periods of the engine: a. completely suppressing the flow of carburetted mixture supplied to said cylinder, and b. introducing non-carburetted air into said pipe at such a point thereof that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is at most equal to one half of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 16

A process for reducing the emission of pollution responsible products from the external carburation engines during the deceleration periods, applicable to the engines having at least one inlet pipe for carburetted mixture connected to carburation means and including a throttle valve, said pipe opening out in at least one cylinder through an inlet orifice provided with means for intermittent closure, this engine including an idling fuel circuit, wherein are performed substantially simultaneously the following operations during the deceleration periods of the engine: a. completely suppressing the flow of carburetted mixture supplied to said cylinder, and b. introducing non-carburetted air into said pipe at such a point thereof that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is at most equal to one half of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 17

A process according to claim 13, wherein the introduction of non-carburetted air into said inlet pipe is effected at such a point thereof that the volume of that part of the inlet pipe of said cylinder comprised between this point and said means for intermittent closure is smaller than one third of the volume of the inlet pipe of said cylinder comprised between said carburation means and said means for intermittent closure.

Claim 18

A process according to claim 13, wherein the introduction of non-carburetted air into said cylinder is effected in the immediate vicinity of said means for intermittent closure.

Claim 19

A process according to claim 13, applied to an engine provided with a circuit for the idling operation and for the transition between the idling and the normal operative conditions of the engine, wherein are effected during a deceleration successively the closing of the throttle valve and of said idling and transition circuit and wherein, conversely, the opening of said idling and transition circuit is effected prior to the opening of the throttle valve, during the return to the normal operating conditions of the engine after a deceleration.

Claim 20

A process according to claim 13, wherein the ignition is interrupted during the deceleration periods.