Abstract: A carburetor has a butterfly valve comprising a first valve plate portion for opening and closing a portion of an intake passage adjacent to a fuel nozzle and a second valve plate portion for opening and closing a portion of the intake passage located farther from the fuel nozzle, wherein the first valve plate portion is first opened from a position of closing the intake passage up to a predetermined angle, and, when the first valve plate portion is opened by more than the predetermined angle, the second valve plate portion is opened from a position of closing the intake passage.

Abstract: A temperature compensated carburetor having a fuel metering system including a variable restriction needle gate valve for varying the effective flow cross-sectional area of the main and/or idle fuel supply duct to modulate the flow rate of fuel to the carburetor venturi mixing passage. The needle gate valve is made of plastic material having a much greater coefficient of expansion than the aluminum carburetor body in which it is adjustably mounted such that differential linear expansion and contraction of the needle valve relative to the carburetor body in response to ambient temperature changes varies the flow-controlling cross-sectional area of the fuel duct inversely relative to ambient temperature changes. The needle valve is a rod-like body with a threaded cylindrical mounting portion at one end threadably secured in a threaded bore in the carburetor body.

Abstract: A diaphragm carburetor for small internal combustion engines of generally standard construction but improved features for facilitating hot starting due to engine heat or environmental heat which transmits to the carburetor. An automatic or manual relief passage from the diaphragm chamber relieves pressure on fuel due to heat conductors so that a rich fuel charge will not be forced into the engine but will release to atmosphere, thus permitting a normal fuel mixture to be directed to the fuel mixing passage upon a restart of the engine.

Abstract: A priming system for the carburetor-fuel pump of an internal combustion engine. The priming system includes a manually actuatable primer that is connected to the fuel chamber of the fuel pump, and priming fuel flows through a primer check valve either directly to an orifice in the carburetor throat or through the metering chamber, which communicates with the carburetor throat through main and idle orifices. In one embodiment, successive actuations of the primer bulb functions to purge the fuel pump, primer and priming lines of air and fill them with liquid fuel so that continued pumping injects priming fuel into the carburetor throat. In an alternative embodiment, the fuel pump, primer and priming lines are similarly charged but the metering chamber is also charged with fuel and the excess fuel is pumped therethrough and into the carburetor throat through the main and idle orifices.

Abstract: A fuel primer for small internal combustion engines is disclosed. The fuel primer is associated with a metering chamber of a carburetor. The metering chamber includes an inlet port and an outlet port and communicates with both a fuel source and a venturi on the carburetor by conventional means. The primer includes a mechanism which communicates with the restricted inlet port to provide one way flow into the metering chamber. A second mechanism communicates with the unrestricted outlet port to provide one way flow from the metering chamber. A third mechanism associates the first and second one way mechanisms for pressurizing and depressurizing the flow through the primer so that fuel is drawn into the metering chamber from the fuel source.

Abstract: A priming system for the carburetor-fuel pump of an internal combustion engine. The priming system includes a manually actuatable primer that is connected through a primer check valve either directly to a fed orifice in the carburetor throat or through the metering chamber, which communicates with the carburetor throat through main and idle orifices. In one embodiment, successive actuations of the primer bulb functions to purge the fuel pump, primer and priming lines of air and fill them with liquid fuel so that continued pumping injects priming fuel into the carburetor throat. In an alternative embodiment, the fuel pump, primer and priming lines are similarly charged but the metering chamber is also charged with fuel and the excess fuel is pumped therethrough and into the carburetor throat through the main and idle orifices. The metering chamber is left with an excess charge of fuel that results in richer operation during cranking and initial engine operation.

Abstract: Apparatus for enabling an engine to burn either liquid fuel or gaseous fuel, which apparatus comprises: a gaseous fuel control valve for installation in a gaseous fuel supply line leading from a gaseous fuel storage container to an intake manifold of the engine, a liquid fuel shut-off valve for shutting off the supply of liquid fuel when the engine is to run on gaseous fuel, and a gaseous fuel shut-off valve for shutting off the supply of gaseous fuel when the engine is to run on liquid fuel, the gaseous fuel control valve being such that it has a diaphragm which is positioned in a chamber and which operates in association with a gas inlet and a gas outlet to the chamber to apportion the gaseous fuel to the engine in dependence upon the operating requirements of the engine.

Abstract: A carburetor for small motors has a housing with a carburetor bore wherein air and fuel are mixed to an air fuel mixture. The fuel enters the carburetor bore through fuel jets. A throttle valve is pivotally mounted in the carburetor bore by means of which the fuel-air mixture quantity is adjusted in dependence upon the operating condition of the engine. The throttle valve and the inner wall surface of the carburetor bore conjointly define an air gap in the idling position. An idling fuel outlet jet communicates with the carburetor bore in the region of this air gap and is connected to the control chamber containing the fuel. The idling fuel outlet jet together with a ventilation bore communicate with an emulsion chamber of the control compartment. Further, an idling control part is provided which is movable into the air gap whereby an outlet opening of the ventilation bore communicating with the emulsion chamber is passed over.

Abstract: A diaphragm carburetor provided with a temperature-sensitive lever arm is disclosed. The temperature-sensitive lever arm permits hot restart of an engine when the carburetor is in a vapor lock condition, without the use of the choke mechanism.

Abstract: An improved carburetor having a system for precisely metering fuel introduced into an internal combustion engine. The carburetor includes an air passageway and a throttle valve having a throttle opening movable across the air passageway to control the effective cross-sectional dimension of the air passageway. The fuel metering system includes an fuel metering tube extending across the air passageway in registration with the throttle valve. The metering tube is either connected to and movable with the throttle valve, or is stationary and extends through a complementary lateral aperture in the throttle valve such that the throttle valve is slidable upon the metering tube. A longitudinal fuel distribution outlet extends along one side of the fuel metering tube substantially across the width of the air passageway.

Abstract: A two cycle internal combustion engine (10) has at least two cylinders (12, 13) which fire alternately with pressure in one crankcase (17 or 18) at the time there is vacuum in the other. Supplemental fuel flow passages (36, 41) extend from each crankcase and are joined at a common passage (46) connected to the float bowl (30) of the carburetor (20). A normally closed control valve (48) is disposed in the common passage. When the engine is to be started, the control valve is opened so that fuel enters the supplemental and common passage. Initial rotation of the crankshaft (16) causes pressure in one crankcase to force fuel toward the other crankcase, which has vacuum. Further crankshaft rotation reverses the pressures so that fuel is then forced toward the opposite crankcase. Continued engine operation with the control valve open causes alternate fuel flow reversals together with pressurized alternate fuel injections into the respective crankcases, which are independent of the throttle setting.

Abstract: A combustion engine includes an inlet duct including a control valve. A vaporizer-pressure regulator for use with the combustion engine has a first space divided into two parts by a diaphragm contained in the space, the diaphragm actuating a first shut-off valve co-operating with a gas supply orifice of the first space, while the part of the space in which the gas supply orifice opens out is connected through a connecting duct with a second space comprising a member affecting the gas pressure, the space communicating with the inlet duct of the combustion engine, whereby that part of the first space which is located on the side of the diaphragm actuating the first shut-off valve remote from the first shut-off valve is connected both downstream and upstream of the control valve with the inlet duct of the combustion engine through a pressure duct network including means acting upon the size of the passage of the ducts in dependence on the load of the combustion engine occurring during operation.

Abstract: A rotary throttle carburetor in which an air passage leading to the engine has a crossbore to receive a cylindrical rotary throttle having a throttle passage to regulate the air passage. A constant pressure device is mounted on the carburetor body directly below the rotary throttle and a short straight fuel passage connects a constant pressure chamber of said device with the throttle passage of the rotary valve. A fuel pump device can be mounted between the carburetor body and the constant pressure device to supply fuel to the constant pressure chamber and also to insulate the constant pressure device from the carburetor body to reduce vaporization.

Abstract: A crank-case pre-compression type 2-cycle engine internal combustion has an intake opening formed in the wall of a crank case and provided with a reed valve therein, and a carburetor disposed at a rearward offset from the intake port. The carburetor is connected to the inlet port through a joint-pipe. The joint-pipe has a mixture passage formed therein, an intermediate contracted portion and a partition plate extending along the axis of the mixture passage. The portion of the mixture passage near the outlet opening thereof is curved to cross the intake port substantially at a right angle to the latter.

Abstract: A carburetor for internal combustion engines, especially for very small portable engines. The carburetor has a control chamber arranged in the carburetor in the fuel supply to the intake pipe. The control chamber is connected with the intake pipe via inlet passages, the rate or quantity of flow through which can be regulated, and is connected with fuel feed supplied by a fuel pump via an inlet valve, which is biased in the closed position. The inlet valve is opened by a control membrane which delimits the control chamber. The control membrane, on that side thereof remote from the control chamber, delimits an equalizing chamber along with a closure cover fastened to the carburetor housing. The equalizing chamber is constructed as a pressure chamber which can be selectively connected via a reversing or change-over valve with either the crankcase housing of the internal combustion engine, or with the atmosphere.

Abstract: A supplementary fuel supply mechanism for internal combustion engines which is incorporated in a carburetor with a manually operated flexible dome to discharge fuel from a supplemental fuel chamber adjacent the air inlet of a carburetor. The device is designed so that it can be interposed between the carburetor body and the air inlet as an auxiliary unit optionally applied.

Abstract: The disclosure embraces a fuel feed and charge forming apparatus wherein the apparatus is of comparatively small size particularly for use with chain saws and other motor driven tools to effect the reduction in weight. The charge forming apparatus embodies a body construction providing external support members to resist creep and bolt-torque deformation, as well as providing a heat sink-heat transfer means. A valve seat construction for shape retention is also provided to inhibit fuel metering distortions caused by deformation of valve seats by carburetor body creep.

Abstract: Apparatus for enabling an engine to burn either liquid fuel or gaseous fuel, and which includes a gaseous fuel control valve for location in a gaseous fuel supply line between a gaseous fuel storage container and an intake manifold of the engine. The control valve includes a single diaphragm which defines one wall of a chamber having a gas inlet and a gas outlet. An accelerator pedal controlled outlet valve obturator is positioned in the outlet, for controlling the intensity of suction applied to the chamber in response to the position of the accelerator pedal. An inlet valve obturator is provided to control the flow of gaseous fuel through the inlet into the chamber. The inlet valve obturator is connected to the diaphragm so that movement of the diaphragm controls of the inlet valve obturator.

Abstract: A carburetion system for an internal combustion engine having improved fuel metering is disclosed and includes a fuel supply conduit which is formed in a portion of the body of the carburetor extending from a fuel source to the carburetor bore with that carburetor body portion having a first linear temperature coefficient of expansion. A mixture control member formed of a material having a second linear temperature coefficient of expansion engages the body in a first region and defines relative to the carburetor body in a second remote region a fuel metering orifice for controlling fuel flow through the fuel supply conduit. The mixture control member may be moved relative to the first and second regions to change the fuel to air ratio supplied to the engine. Employing a fuel metering orifice in the adjustable fuel metering arrangement, the minimum flow area of which has a simply connected convex cross sectional configuration, minimizes the adverse effects of ambient temperature changes.

Abstract: A charge forming device for an air breathing internal combustion engine (10) includes main and mixing air manifold (40) (63) for each cylinder (14), a fuel distribution port (62) in each mixing manifold (63) facing towards the intake valve (30) of each cylinder, with the fuel of each charge being supplied solely through the fuel distribution port and entrained, with a proportion of fuel carrier air supplied by a carrier air duct (54) in communication with the fuel distribution port into the main engine air supply flowing through the main and mixing manifolds. The fuel distribution port is large and is shaped to divert expansion waves induced in the charge upstream of the intake valve by the kinetics of the interrupted charge flow out of the mixing manifold and into a temporary holding area, and to allow compression wave flow of fuel-free air from the main manifold towards the intake valve so that fuel-free air accumulates near the intake valve between engine intake events.

Abstract: Disclosed is a pulse-jet engine powered, fog producing device using a carburetor to feed atomized fuel to the engine combustion chamber, the carburetor operation being characterized by a positive pressurization of a diaphragm-walled chamber to open a fuel inlet valve during the engine starting interval, and provision of a positive pressure fuel delivery to the carburetor utilizing the combustion pressure pulses of the engine as the fuel pumping impetus.

Abstract: In a carburetor for furnishing fuel to internal combustion engines and utilizing a cylindrical rotary throttle valve as the venturi of the mixing passage, the addition of a fuel retaining means of absorbent material to prevent the puddling of unused fuel during the idling cycle and thus avoiding the problem of an overrich mixture when the carburetor is moved to another position.

Abstract: In a compensating membrane carburetor having a fuel accumulating chamber connected through idling and high-speed jets to a Venturi, a compensating chamber is provided which is maintained, naturally or artificially, at atmospheric pressure. A second chamber seals the external face of the compensating membrane from the environment of the carburetor and a first relief line, partially disposed in the carburetor, provides fluid communication between the compensating chamber and the second chamber to maintain the second chamber at atmospheric pressure. A second relief line is disposed substantially outside of the carburetor and also provides fluid communication between the compensating chamber and the second chamber, in order to insure the proper operation of the carburetor in the event of a blockage in one of the two lines.

Abstract: An induction system for an internal combustion engine that improves efficiency through increasing flame propagation at low and medium speeds and loads. This is accomplished through the use of a relatively small cross sectional area auxiliary induction system through which at least a portion of the charge requirements are supplied. The small cross sectional area causes the charging to be introduced at a high velocity, thus increasing turbulence in the intake charge to promote rapid flame propagation when the spark plug is fired. At least a portion of the idle charge is also delivered through the main induction passage so as to reduce the velocity of the intake charge. The charge delivered through the main induction system flows at an angle to that discharged from the auxiliary induction system so that the two flow paths will create internal turbulence due to their different directions.

Abstract: A carburetor having a fuel pump connected to a fuel supply, a fuel inlet valve, a diaphragm-controlled fuel chamber, and a diaphragm to control said fuel inlet valve in response to sub-atmospheric engine pulses, with a manually operable resilient pressure dome to create a sub-atmospheric pressure in the fuel chamber to move said diaphragm to an inlet valve open position and pull fuel into said chamber from a fuel supply to prime said carburetor for cold starts or restarts after fuel depletion.

Abstract: A carburetor of the membrane type for correct operation of an engine partially or completely submerged in a liquid such as water. The carburetor has a fuel accumulating chamber which is connected through conventional idling and high-speed jets to a Venturi upstream from which there is provided an air intake manifold. Externally of the compensating membrane that is provided a sealed chamber which communicates via a flexible tube with a compensating chamber which is maintained naturally or artificially at atmospheric pressure.

Abstract: A retainer for plastic carburetors which eliminates the necessity for mating flanges bolted together and thus avoids distortion of the body due to clamping pressures. The carburetor body has male parts which insert into recesses in an engine block or heat dam to seal in relation thereto and a forked clamp embraces a necked portion of the carburetor body and is clamped in cantilever fashion so that the plastic body is retained securely without distortive forces.

Abstract: A port in the cylinder wall of a two-stroke cycle engine is connected by a passage and a restricted orifice with the idle reservoir of a diaphragm type carburetor. The idle reservoir is connected through an adjustable idle mixture valve with the metering chamber. The passage from the engine port is connected by a vent passage with the venturi of the carburetor. The dry side of the metering diaphragm is vented by a restricted opening and is connected with the dry side of a crankcase pressure operated fuel pump through a passageway having therein a check valve and a valve which is open when the choke valve is closed. This connection allows pressure pulses from the crankcase to influence fuel flow so that the desired fuel flow is obtained under more than one engine operating condition. In addition fuel is introduced directly into the crankcase at idle speeds instead of into the throttle bore giving more stable idle condition.

Abstract: A small carburetor for chain saws and the like which needs no fuel pump. A spring-biased diaphragm has a radically higher bias than is normal and controls a fuel inlet valve open to the tank such that a higher vacuum is needed to open the valve, thus providing the necessary pull to draw fuel from a tank in any position relative to the fuel tank whether below, above, or to the side of the carburetor. An on-off check valve is interposed between the diaphragm fuel chamber and the main fuel orifice to insure constant negative pressures in the diaphragm chamber. The carburetor body, molded from plastic, has a composite jet insert and plug-in connection to the engine.

Abstract: The disclosure embraces a charge forming apparatus or carburetor embodying a fuel aspirating system and method of operation thereof wherein the charge forming apparatus comprises a body construction having a mixing passage, a fuel chamber and aperture means for delivering fuel into the mixing passage, the fuel aspirating system utilizing a jet of gas projected across the aperture means and being of sufficient velocity for aspirating fuel from the aperture means into the mixing passage effective for improved engine operation, engine acceleration purposes and efficient fuel metering.

Abstract: A carburetor and fuel feed device for small internal combustion engines incorporating a pumping section which receives fuel from a supply and delivers the required amounts for the range of operation between high and low speed operation with any excess being returned to the source of supply. A control device is employed which permits deceleration from high to low speed operation without flooding by instantaneously preventing the supply of fuel for high speed operation in response to movement of the throttle valve to an idle or low speed position.

Abstract: A carburetor construction is disclosed which includes a plurality of plate members stacked one upon the other, the plates including recesses and openings which define fuel channels, and cavities which nestibly receive various components of the carburetor, the components being designed so as to facilitate assembly with each other.

Abstract: A hot fuel gas generator for an internal combustion engine simultaneously vaporizes gasoline and water in a multi-chambered heated pressure vessel having built in regulators for controlling pressure and volume and delivers the resulting superheated steam and gaseous fuel to the internal combustion engine downstream from the usual carburetor. A single device operating at a very high temperature, for example 1600.degree. F., is used for the simultaneous vaporization of the fuel and water to develop desirable working pressure and volume. The high temperature steam and gaseous fuel positions the fuel molecules at the greatest degree of separation from each other providing the greatest opportunity for contact of the oxygen, the reacting species in the gaseous condition as chemical reactions occur only between particles at the atomic or molecular level and it is necessary for the reacting species to be in actual contact at the time of reaction.

Abstract: An economizer valve for use with an induction and fuel supply system for an internal combustion engine operated on gaseous fuels, for example, LPG or natural gas. The system is used with a conventional mixing valve which supplies air according to engine demand, together with fuel appropriate to the desired charge, and includes a regulator for providing gas to the mixing valve, and an economizer valve responsive to pressure regions upstream from and at and downstream from a throttle valve, effective on the regulator to cause it to lean out the charge under certain conditions and to permit the charge to be enriched at other conditions.

Abstract: The disclosure embraces a charge forming apparatus or carburetor and method of operation thereof wherein the charge forming apparatus is of modular construction and is inclusive of a body construction and a fluid flow control construction associated with the body construction, the fluid flow control construction being of laminar character fashioned with open areas or passages accommodating fluid flow or transfer, the fluid flow control being of a character enabling the interchangeability of fluid flow control laminations having different or modified patterns or arrangements of open areas or passages whereby the method of operation or the operating or metering characteristics of the charge forming apparatus may be changed or modified without alteration of the body construction.

Abstract: A cover plate for a carburetor having a gasket interposed between the plate and the carburetor body which comprises a plate of rectilinear shape with a bottom peripheral surface to seal against the gaskets on a carburetor body and having a central upstanding boss on the outside of the plate with tapered ribs extending from the top of said boss to the corners of the plate. A screw with a tapered head passes through a tapered opening in said boss and exerts pressure on said ribs to urge the entire plate in tight contact with the carburetor body.

Abstract: A carburetor and fuel feed device for small internal combustion engines incorporating a pumping section which receives fuel from a supply and delivers the required amounts for the range of operation between high and low speed operation with any excess being returned to the source of supply. A control device is employed which permits deceleration from high to low speed operation without flooding by instantaneously preventing the supply of fuel for high speed operation in response to movement of the throttle valve to an idle or low speed position.

Abstract: The disclosure embraces relatively movable or adjustable members or elements forming control components of a charge forming apparatus or carburetor wherein one or more members or elements are adjustable or movable relative to a mounting means, the disclosure embracing a method and arrangement wherein substantially spherical bodies or balls of deformable resinous or plastic material associated with the movable members or elements are disposed to establish a substantially constant amount or degree of friction between a mounting means and one or more of the movable or adjustable members or elements to assure retention of the movable members or elements in adjusted positions.

Abstract: A pressure regulator of the liquefied-gas fuel system for internal combustion engines has two cooperative diaphragms which partition the space inside the regulator body into three separate chambers. The diaphragms are operatively connected by a spring disposed therebetween, the first one defining two of the three chambers, namely a pressure-regulating chamber and a back-pressure chamber, and the second one defining the back-pressure chamber and a suction-pressure chamber. In the pressure-regulating chamber is installed a valve whose opening is controlled by the first diaphragm to control the supply of the liquefied-gas fuel. The second diaphragm is moved according to the intake-manifold vacuum, and the first diaphragm is correspondingly moved to control the valve, thus regulating the pressure of the fuel in the pressure-regulating chamber.

Abstract: The disclosure embraces a charge forming apparatus or carburetor and method of operation thereof wherein the charge forming apparatus is of modular construction comprising a body construction and a fluid flow control system including a laminar means or member having perforate fuel conveying regions including a channel for conveying fuel from a fuel chamber to an engine idling and low speed orifice system in association with a passage arranged to receive pressure pulses from the engine crankcase under open throttle conditions for discharging fuel in the channel through an aperture means independent of the main and engine idling fuel delivery aperture means into the air induction system of the charge forming apparatus for engine acceleration purposes, the fuel conveying channel being of substantial length and of a cross sectional area to effect delayed fuel flow to the engine idling system to avoid formation of an overrich mixture which would result in stalling the engine.

Abstract: The invention disclosed embraces a charge forming method of and apparatus embodying an instrumentality responsive to engine vibrations or disturbances brought into operation when the engine reaches a predetermined speed to automatically deliver excess fuel to the engine thereby momentarily providing a nonignitible mixture preventing overspeeding of the engine.