FUEL SAVING APPARATUS

Abstract: Fuel saving apparatus for a combustion engine having a combustion air intake region where air is introduced into the engine for subsequent mixing with combustion fuel and an exhaust gas region where combustion products are exhausted from the engine, the apparatus comprising a container for holding a supply of water, a flow passageway disposed between the container and the air intake region for fluid flow from the container to the air intake region, the flow passageway passing through the exhaust gas region so that, in use, water flows in the flow passageway from the container to the exhaust gas region where it is generated into steam and the steam thereafter flows in the flow passageway to the air intake region for entrainment into intake air flowing into the air intake region of the engine.

Description: TITLE FUEL SAVING APPARATUS DESCRIPTION The present invention relates generally to apparatus for reducing engine fuel consumption, and in particular to such apparatus for generating and delivering steam to the combustion fuel of an internal combustion engine in order to reduce the fuel consumed by that engine. The apparatus is applicable to liquid or gas fuel engines, such as petrol, diesel and LPG gas engines, installed in vehicles including landcraft, watercraft, and aircraft. It is to be appreciated, however, that the apparatus of the invention is not limited to that application. FIELD OF THE INVENTION It is well recognised that the inclusion of a measured quantity of steam in fuel delivered to an internal combustion engine can improve overall fuel economy. One such arrangement is disclosed in Australian patent appli- cation 68960/81 where water from a supply tank flows in a fluid passage passing through the engine exhaust gases where the water is heated so as to generate steam, and the resulting steam is then delivered into previously mixed combustion fuel and air flowing into the engine cylinders. The water flow and thus steam generated is regulated by means of a manually or automatically actu¬ ated valve, with the steam being drawn into the fuel-air mixture, tomix therewith under a suction effect created by the mixture flow. An expected disadvantage of this arrangement is that the suction effect is excessive, so that sometimes water will be drawn into the fuel-air mixture before it has been heated to steam by the exhaust gases. Water so introduc¬ ed will adversely affect fuel consumption and thus engine performance. In addition, the water may find its way into ' the engine oil sump and other engine components increasing the possibility of engine corrosion or other deterioration. A further disadvantage with this arrangement is that close monitoring of the valve is required to ensure that only predetermined regulated quantities of water are delivered for heating by the exhaust gases. In that regard-, valve adjustment will be necessary as the temper¬ ature of the engine, and in particular the temperature of the exhaust gases, vary. Where the valve is manually actuated, constant valve adjustment can be tiresome, whilst automatic actuation can complicate and thus add_ considerable expense to the overall arrangement. SUMMARY OF THE INVENTION It is an object of-the present invetion to provide a relatively simple and inexpensive engine fuel saving apparatus which may alleviate the above mentioned disadvantages. In accordance with the present invention there is provided a fuel saving apparatus for a combust¬ ion engine having a combustion air intake region wher-s air is introduced into the engine for subsequent mixing with combustion fuel and an exhaust gas region where combustion products are exhausted from the engine, the apparatus comprising a container for holding a supply of water, a flow passageway disposed between the container and the air intake region for fluid flow from the contai- ner to the air intake region, the flow passageway passing through the exhaust gas region so that, in use, water flows in the flow passageway from the container to the exhaust gas region where it is generated into steam and the steam thereafter flows in the flow passageway to the air intake region for entrainment into intake air flowing into the air intake region of the engine. The present invention will now be described, by way of example, with reference to conventional internal combust¬ ion engines as used in landcraft and not being fuel injected. DESCRIPTION OF THE INVENTION A fuel saving apparatus in accordance with the ' present invention comprises a supply container mounted either adjacentto or remote froman engine having the fuel saving apparatus fitted. The supply container has, in use, a store of water. It is envisaged that the supply container maybe mounted adjacent the engine and arranged relative thereto so that water flow from the supply container is under the influence of gravity. This arrangement alleviates the necessity for auxiliary flow means such as pumps. How¬ ever, it is to be understood that a pump may be installed as necessary to assist in such.flow. The supply tank, is provided with a cap or lead to : allow access for water replenishment. The supply container may have any suit¬ able water storage capacity, such as about 4 to 20 litres in the present example. The fuel saving apparatus also comprises a flowpassage¬ way extending between the supply container and an air in-take of the engine. The flow passage way has an inlet opening into the supply container for receiving water thereform. The flow passageway also has an outlet opening into the air inlet region of the engine. The flow passageway inlet is located at or adjacent the bottom of the supply container to facilitate water flow therefrom. The flow passageway outlet is positioned immediately beneath the path of an air stream that is caused to pass through the air inlet region in use. The outlet preferably faces upwardly toward the path of the air stream immediately adjacent an inlet port through which air enters the air inlet region. In this way, a jet fountain of steam described hereinafter) can issue from the flow passageway outlet for entrainment on demand into the air stream in use. It has been found that disposed of the outlet in the air intake region in a direction not contrary to the airstream may result in excessive suction being induced in the flow passageway. Such excessive suction may lead to exces.sive demand for steam and may result in insufficient steam production and water may be drawn into a combustion chamber of the engine with the air stream. This water may then contaminate sump oil and may flow to the exhaust system. The flow passageway passes through an exhaust gas region of the engine intermediate the inlet and outlet thereof. The exhaust gas region may be an exhaust manifold or an exhaust pipe of the engine. The flow passageway comprises a steam generating section which passes through the exhaust gas region. Preferably, the steam generating section is. arranged, in use, at a location in the exhaust gas region that is as close as practical to where the exhaust gases are hottest and can freely heat water in that section of the flow passageway to generate steam. Such is preferred to enable complete and proper steam generation to occur most effici¬ ently. Preferably, the steam generating section is located adjacent the engine combustion cylinders. It has been found that motor vehicle manufacturers are opposed to modifications of the exhaust manifolds and/or exhaust pipes fitted.to the vehicles they produce. Thus, it is preferred to arrange the steam generating section in the exhaust gas region without modifying either the exhaust manifold or the exhaust pipe. This can be achieved by inserting the steam generating section in a flange at the junction of the exhaust manifold and the exhaust pipe and disposed in the inter- ior thereof. The steam generating section is preferably sufficient to create steam fromthe water flowing in that section when in use. The steam generating section preferably has a length selected with due regard to the operating te p- eratures of the exhaust gases, the operating temperature of the water, and also the water flow rates through the steam generating section, in order to ensure that steam is generated from the water in that section. The steam generating section of the flow passageway is shaped as necessary to fit into the desired location within the exhaust g..s region and so that the gases can flow along the exhaust manifolds exhaust pipe about the steam generating section and the atmosphere in known manner. The hot exhaust gases flowing about and past the steam generating section heat the steam generating section and thus water in it. The steam generating section is preferably wound into a helix or spiral shape having a length dependant upon the engine capacity and the temperature of the exhaust gases and the temperature of the water and may be for example about 150 millimetres long. It has been found that a helix or spiral shape is prefer¬ red to a straight piece of pipe since the latter results in the production of bursts of steam whereas the former results in a continuous flow of steam. The flow passageway may be of constant cross-sectional shape and size, and material throughout its length. The flow passageway may be constructed of stainless steel and have a circular cross section. The internal diameter of the flow passageway is dependant upon the required flow rate of water described herein- above. That is the internal diameter of the flow passageway is principally dependant upon the engine capacity. It has been found that for vehicular engines having a capacity less than 4 litres the internal diam¬ eter preferably is not more than about 1.5 to 2.0 mill¬ imetres. Also for vehicular engines having a capacity greater than 4 litres the internal diameter preferably is not less than about 2.0 to 2.5 millimetres. Where the diameter is too large insufficient steam may be produced and some water may enter into the engine. Where the diameter is too small the water may become superheated and vapourize and not flow to the air intake region. - The fuel saving apparatus of the present invention also comprises a steam relief unit disposed in the flow passageway intermediately of the supply container and the steam generating section. The steam relief unit has an upstream portion of the flow passageway entering at an upper end and a downstream portion entering at a lower end. The steam relief unit has an intermediate store of water derived from the supply container. Steam generated in the steam generating section may tend to flow in both directions along the passageway toward both the flow passageway inlet and outlet. The steam is intended to flow toward the flow passageway outlet. Steam flowing back toward the flow passageway inlet may interrupt the water flow between the supply container and the steam generating section. The steam relief unit is arranged to relieve the flow passageway of steam backflowing ' from the steam generating section. The relief unit is preferably interposed in the passageway between the supply container and steam generating section so that the steam is relieved before it reaches the supply container. Preferably, the steam relief unit comprises a closed relief chamber with which the flow passageway commun¬ icates. Thus, the flow passageway preferably opens into a top of the relief chamber so that water flowing from the supply container passes through the relief chamber to the steam generating section. Any steam back-flowing from the steam generating section is intended to flow from the flow passageway into the relief chamber at a bottom thereof. Back-flowing steam is intended to expand into the relief chamber and generally condense into water. The relief chamber may have any suitable capacity for example about 0.5 litres for a 4 litre engine. The steam relief unit preferably also comprises a press¬ ure relief passageway extending from the relief chamber to the atmosphere or to the supply chamber. In the latter case the pressure relief passageway has an inlet located in the top of the relief chamber and an outlet located in a top of the supply container. This allows for steam built up in the relief chamber to be vented to the supply container where it may condense. The pressure relief passageway is intended to relieve any pressure build-up in the relief chamber, caused by the back-flowing steam. The fuel saving apparatus may also comprise a drain disposed in the air inlet region for removal of any condensate therefrom. The drain may remove the condensate to surrounding atmosphere or return the condensate to the supply container. Condensation of steam may occur in the air intake region when the engine is at low revolutions and only a small amount of steam is demanded. The fuel saving apparatus of the present invention may also comprise a valve to control flow of water from the supply container. It is envisaged that the valve be operable to connect and disconnect the supply container this has the effect of selectively connecting and disconnecting the apparatus from- the engine as desired. The valve may be a stop cock having an open position in which water can flow from the supply container and a closed postion in which that water flow is prevented. The stop cock may be manually actuable, or automatically actuable upon operation of the engine igntition to start and stop the engine. In use, the fuel saving apparatus of the present invention is installed onto an engine, such as a vehicle engine, operating in a normal manner. With the engine operating, combustion air is drawn in a stream through the air inlet region past the flow passageway outlet for subsequent mixing with combustion fuel. In addition, hot exhaust gases from the engine flow through the exhaust gas region from the engine. Upon engine start up, the stop cock is opened to allow water from the supply container to flow along the flow passageway through the pressure relief unit and then through the steam generating section located within the exhaust gas region. Hot exhaust gases from the engine within the exhaust gas region heat the steam generating section and have the-water within the steam generating section to generate steam. The steam in turn flows under pressure to the air intake region of the engine where it leaves the flow passageway outlet in a jet fountain issuing into the air stream contrary to the flow thereof. The steam is drawn into the air stream upon demand from the engine and mixed homogenously therewith. The amount of steam demanded increases with the demand for air and thus when engine revolutions. When the demand is low excess steam condenses-and s removed from the air intake region by the condensate drain. Steam from the steam generating section also tends to back-flow along the flow passageway toward the pressure relief unit. Upon reaching the relief chamber, back-, flow steam may mix with any incoming water from the supply container and condense. Any build-up of pressure within the relief chamber.is relieved through the pressure relief passageway returning any water to the storage tank or atmosphere. Apparatus according to the present invention has been found through initial tests to provide a substantial fuel economy increase over fuel consumption prior to installation of the apparatus. The fuel saving has been achieved with no reduction in the engine performance. Indeed, engine operation is improved and performance increased as a resultof the inclusion of the steam. The reduction in fuel consumption has an advantage in reducing the costs of engine operation. In addition, valuable fuel sources may be conserved. Modifications and variations such as would be apparent to a skilled addressee are deemed within the scope of the present invention.

Claims: CLAIMS 1. A fuel saving apparatus for a combustion engine having a combustion air intake region where air is introduced into the engine for subsequent mixing with combustion fuel and an exhaust gas region where 5 combustion products are exhausted from the engine, the apparatus characterised in that it comprises a container for holding a supply of water, a flow passage¬ way disposed between the container and the air intake region for fluid flow from the * container to the air 10 intake region, the flow passageway passing through the exhaust gas region so that, in use, water flows in the flow passageway from the container to the exhaust gas region where it ' is generated into steam and the steam there¬ after flows in the passageway to the air intake region 15 for entrainment into intake air flowing into the air intake region of the engine. 2. A fuel saving apparatus according to claim 1, characterised in that flow passageway comprises a steam generating section passing through the exhaust gas 20 region, the steam generating section being in the form of a helix or spiral. 3. A fuel saving apparatus according to claim 1 or 2, characterised in that the steam generating section is disposed in the exhaust gas region in a flange at the Λ 25 junction of an exhaust manifold and an exhaust pipe of the engine such that exhaust gases flowing therein contact the steam generating section and then flow to the atmosphere. 30 4. A fuel saving apparatus according to any one of the preceding claims, characterised in that the flow passageway comprises an outlet arranged, in use, in the air intake region contrary to the flow of air induced therein during engine operation. 5. A fuel saving apparatus according to claim 4, characterised in that the outlet, as used in an engine h"ving a capacity less than about 4 litres, is not more than 1.5 to 2.0 millimetres in diameter. ° 6. A fuel saving apparatus according to claim 4, characterised in that the outlet as used in an engine having a capacity more than about 4 litres, is not less than 2.0 to 2.5 millimetres in diameter. 7. A fuel saving apparatus according to any one of 5 the preceding claims, characterised in that it comp¬ rises a steam relief unit disposed in the flow passage¬ way intermediately of the supply container and the steam generating section and arranged to remove steam that may flow in the flow passageway toward the supply 0 container and/or relieve pressure build up caused by t e steam. 8, A fuel saving apparatus according to any one of the preceding claims, characterised in that it comp¬ rises a condensate drain arranged to remove condensate which forms in the air intake region of the engine.

Inventors: SASIN MIECZYSLAW, SASIN, MIECZYSLAW
Applicants: SASIN MIECZYSLAW, SASIN, MIECZYSLAW
Application year: 1985
Main classification: F02M25
IPC codes: F02B3, F02B47, F02M25