This invention relates to a device for saving fuel during deceleration of a motor vehicle.
During deceleration of motor vehide, the throttle is closed and high vacuum is created at the intake manifold/intake pipe, causing more fuel to flow into the combustion chamber which will be waste as exhaust emission. Apart from this, since there is no power requirement during deceleration the extra fuel
supply is unnecessary and since the throttle is closed during deceleration there is no airflow, and the combustion will be poor as a result of a rich fuel mixture.
It is therefore an object of this invention to propose a device for saving fuel during deceleration periods of a motor vehicle. Additionally, the said device results in smooth running of the vehicle during deceleration.
The device for saving fuel during deceleration of a motor vehicle, according to this invention, comprises means for directly connecting the air filter and pipe intake of the engine of the said vehicle, whenever said means is activated by the vacuuin created in the intake manifold on closing of the throttle, such that more air is allowed to flow to pipe intake of the engine and thereby substantially reduce the said vacuum in the said manifold and thus substantially reduce the fuel drawn from the carburetor of the said engine, the diaphragm the a filter reverting to its normal state under spring force.

This invention will now be described with reference to the accompanying drawings which illustrate, by way of example, and not by way of limitation, in the single Figure therein, one of possible embodiments of the device proposed herein.
In the embodiment illustrated, means are provided for directly connecting the air filter F and pipe intake P of the engine of the said vehicle bypassing the carburetor C, whenever said means is activated by the vacuum created in the intake manifold as a result of closing of the throttle of the engine. Thus more air is allowed to flow to pipe intake P and thereby substantially reduce the said vacuum in the said manifold and thus substantially reduce the fuel drawn from the carburetor of the said engine.
In the embodiment illustrated the said means are

exemplified as consisting of a spring-loaded diaphragm D (spring being indicated by S) in the air control valve A, said diaphragm sensing the vacuum in the intake manifold and flexing under vacuum pressure to open the said valve to allow more air to flow to the pipe intake, bypassing the carburetor C. This air flow substantially reduces, if not eliminates, the said vacuum in the said manifold and thus substantially reduces the fuel drawn from the carburetor of the said engine,
Once the vacuum is reduced, or eliminate4 the diaphragm reverts to its normal state under spring force.

The terms and expressions in this specification are of description and not of limitation, surface it will be appreciated that various other embodiments of this invention are possible without departing from the scope and ambit of this invention.

We Claim:
1. A device for saving fuel during deceleration of a
motor vehicle comprising means for directly
connecting the air filter and pipe intake of the engine
of the said vehicle, whenever said means is activated
by the vacuum created m the intake manifold on
closing of the throttle, such that more air is allowed to
flow to pipe intake of the engine and thereby
substantially reduce the said vacuum in the said
manifold and thus substantially reduce the fuel
drawn from the carburetor of the said engine, the
diaphragm there a filter reverting to its normal state under spring force.
2. A device as claimed in Claim 1 wherein the means consist of a spring loaded diaphragm provided for the air control valve, said diaphragm sensing the vacuum in the intake manifold and flexing under vacuum pressure to open the said valve and allow more air to flow to the pipe intake,
3. A device for saving fuel during deceleration of a motor vehicle substantially as herein described with reference to, and as illustrated in, the accompanying drawings.