Abstract: A vaporized fuel controller for a carburetor which utilizes the negative pressure in the intake manifold and electromagnet to actuate a changeover valve so as to connect the gas chamber of the float chamber to the inner vent when the engine is running, and to the canister when the engine is not running. With this invention, when the negative pressure in the intake manifold decreases while the engine is running at high speeds, the electromagnet keeps the valve from being moved by the spring force and maintains the valve at a position such that the vapor fuel is supplied to the intake manifold through the inner vent.

Abstract: An air-fuel ratio control device for controlling the air-fuel ratio of a mixture to be supplied into an internal combustion engine. The device has a control circuit adapted to produce, in accordance with the offset of the output of an oxygen sensor in the exhaust system of the engine from a reference value corresponding to the desired air-fuel ratio, a control signal for making the air-fuel ratio coincide with the command air-fuel ratio. The device further has a mixture supplying means including means for adjusting the air-fuel ratio in accordance with the control signal. The air-fuel ratio adjusting means includes an actuator incorporating a step motor adapted to change the opening area of fuel passage or air bleed passage of a carburetor.

Abstract: An air-fuel ratio controller of a variable-venturi type carburetor having an air inlet port opening at the upstream side of the suction piston, a branching chamber connected to a passage leading from the air inlet port and branching the passage into a bleed-side passage leading to the bleed portion of the carburetor and a by-pass passage leading to the downstream side of the suction piston, and a valve device disposed in the branching chamber. The valve device is adapted to move reciprocatingly to vary the areas of the bleed-side passage and the by-pass passage relatively in such a manner that, when the area of one of the passages is increased, the area of the other passage is decreased. In consequence, the position of the suction piston is never changed by the change in the amount of bleed air, so that the control of the air-fuel ratio of the mixture is very much facilitated.

Abstract: A vent changeover device for carburetors comprising two working ends provided on a piston rod of a piston moving in a suction chamber, one of which constitutes a rod end of the piston and the other of which constitutes an angle member joined to an end portion of the piston rod, an inner valve being actuated by the angle member so as to open and close an inner vent, an outer valve being actuated by the rod end so as to open and close an outer vent and disposed so as to face in a direction opposite to the direction in which the inner valve faces, and springs biasing the inner and outer valves, respectively, in vent-closing directions, the vents communicating with the fuel bowl via the respective valves, the inner and outer valves being adapted to be actuated in accordance with the movement of the piston rod such that when one of the valves is opened, the other is closed, the inner vent being opened only when the engine is rotated, and the outer vent being opened only when the engine is stopped.

Abstract: An altitude compensation device for automobile engines or the like having a bellows adapted to detect the altitude and a plurality of valve mechanisms adapted to be actuated by the expansion or contraction of the bellows to adjust respective compensation air. The device has a disc mounted in the body of the device for free up and downward movement keeping a horizontal posture. The disc is carried by the bellows making a point contact with the central portion of the upper face of the bellows, so that it is almost free from the tilting of the bellows attributable to a vibration or the like. The valve mechanisms are operatively supported by the disc so as to be actuated uniformly by the bellows through the medium of the disc. Also, means are provided for adjusting the valve mechanisms independently of one another.

Abstract: An adjusting screw of a carburetor comprising a threaded portion, an enlarged head portion and a reduced diameter portion located therebetween. A thin hollow cylindrical wall is formed on a link lever of the carburetor. After the adjusting screw is screwed into the threaded hole of the hollow cylindrical wall, the reduced diameter portion of the adjusting screw is cut. Then, the top portion of the hollow cylindrical wall is bent inward for irremovably fixing the adjusting screw onto the link lever.

Abstract: A device for controlling evaporative emission from an automobile, which device comprises, a casing accommodating fuel gas absorbing agents, a tank port adapted to communicate with a fuel tank of the automobile and having a first check valve for permitting the flow of fuel gas from the fuel tank into the casing, and a purge port adapted to communicate with an internal combustion engine and having a second check valve for permitting the flow of fuel gas from the casing to the engine. Each of the check valves of the first and second check valves comprises a check ball of metal, and a valve seat engaging with the check ball and being made of thin metal plate formed in one body with a reinforcement of plastic.

Abstract: An air-fuel ratio control device for controlling the air-fuel ratio of the mixture to be supplied to internal combustion engine, in which a control level can be made to shift instantaneously even if the engine running condition changes abruptly so that smooth and accurate control of the air-fuel ratio can be performed. Integrators in the control circuit are provided with limiters to place upper and lower limits on the integrated value so as to prevent hunting under the idling condition.

Abstract: A feedback type variable venturi carburetor in which the negative pressure regulated by the variable venturi at a constant level is supplied to a solenoid valve which is opened and closed at a frequency of 5-30 Hz and whose open-close time ratio is controlled in accordance with the signal from exhaust gas sensor to control the vacuum pressure applied to a diaphragm chamber of an air-bleed flow control means thereby controlling the air-fuel ratio of the mixture at an optimum level. This invention obviates the use of a regulator for regulating the negative pressure from the intake manifold and precludes the drawbacks experienced with conventional carburetors, such as the slow response in the feedback control caused when the main fuel system and the idling system of the conventional carburetor are switched over, and the unstable supply of fuel when the fuel begins to be delivered from the main fuel system.

Abstract: A variable venturi type carburetor having a suction piston movable in response to the intake air flow rate to maintain a substantially constant flow velocity at a venturi portion defined between itself and the opposing wall of the carburetor body, the suction piston being provided at its bottom with a pair of partition plates having exponential, arcuate or tapered end surfaces, in order to suppress self-excited oscillation of the suction piston. The pair of partition plates being opposed by a bridge formed on the wall of the carburetor body to form therebetween a diverging opening. The distance between the pair of partition plates and the bridge is independently adjustable to make it possible to maintain a desired size of gap to avoid the fluctuation of fuel metering characteristics.

Abstract: An air-fuel ratio control device capable of accurately controlling the air-fuel ratio of the mixture to be supplied to the engine, without being affected by the external conditions such as the atmospheric pressure and the temperature of the air drawn into the engine. The control signal of the air-fuel ratio control device contains a sensitivity component whose magnitude varies in proportion to a time of duration for which the "rich" or "lean" input signal has continued, so that the air-fuel ratio of the mixture can be properly controlled for all engine running conditions, i.e., either when the engine is running under a light load condition or under a heavy load condition.

Abstract: A carburetor for supplying the mixture of optimum air-fuel ratio to the engine at all times under any accelerating condition. The carburetor comprises a fuel adding valve and associated valve mechanism whereby when the vacuum pressure in the suction pipe decreases as a result of acceleration, the fuel adding valve is opened to deliver extra fuel in addition to the main fuel to produce the mixture of optimum richness. With this invention, the conventional drawback can be precluded that after the first stage of acceleration the mixture becomes leaner than is required.

Abstract: A fuel supplying device for use in fuel injection type internal combustion engine. The device has a fuel metering device operatively connected to an air valve device disposed in the air horn upstream of a throttle valve, fuel supplying means adapted to supply the fuel at a constant supplying pressure to the fuel metering device, a constant differential pressure valve arranged to maintain a predetermined differential pressure across the fuel metering device, and an injector for discharging the metered fuel into the air horn in the vicinity of the throttle valve. The constant differential pressure valve includes a diaphragm type valve arranged to sense and amplify differential pressure across the fuel metering device, and a variable orifice type flow control device arranged to charge flow resistance of the metered fuel.

Abstract: A floatless variable venturi type carburetor in which the float chamber is substituted by a fuel pressure regulator. The carburetor has, in addition to the ordinary constituents such as variable orifice, fuel metering jet and air bleed, a fuel valve disposed in the fuel passage leading to the fuel metering jet and adapted to be opened and closed in relation to the turning on and off of the engine key switch, and a fuel pressure regulator adapted to regulate the pressure of the fuel introduced to the fuel metering jet through the fuel valve. The fuel pressure regulator has two regulating chambers, one of which being communicated with the inlet side of the fuel valve while the other being in communication with a venturi vacuum pickup port, so that the fuel pressure regulator maintains a constant pressure differential, by the action of a diaphragm separating two regulating chambers, between the fuel pressure at the inlet side of the fuel metering jet and the venturi vacuum.

Abstract: An air-fuel mixture supplying device for internal combustion engines, in which sonic nozzles are disposed facing each other in such a manner that their center lines lie in the same horizontal and vertical planes so that the fuel ejected from the nozzle is pulverized and mixed with bleed air ejected from the opposing nozzle in optimum condition. During intermittent ejection of fuel, two injector valves inject fuel alternately so that the fuel particles ejected from the opposing nozzles do not collide with each other but only strike against and mix with the bleed air. This eliminates the possibility of fuel particles becoming agglomerated and produces desirable air-fuel mixtures.

Abstract: An air-fuel ratio control device characterized by the fact that an electromagnetic valve which controls the air bleed quantities for both high- and low-speed fuel systems simultaneously has a pin inserted in a valve disc so as to prevent the rotation of the valve disc but allow it to move axially for open-close operation, so that the valve disc and the seat always contact at the same contacting portion and maintain a perfect seal therebetween. This enables an accurate control of the air bleed quantitiy and therefore of the air-fuel ratio.

Abstract: A carburetor for internal combustion engines includes an inner vent passage through which the space on the free surface of liquid fuel in a float chamber is communicated with the intake passage of the carburetor and an outer vent passage through which the space in the float chamber is communicated with a charcoal canister adapted to store the fuel vapor coming from the space in the float chamber. A valve is movable between a first position in which the inner vent passage is closed and the outer vent passage is opened and a second position in which the inner vent passage is opened and the outer vent passage is closed. A pressure responsive valve actuator is operative in response to the vacuum in the intake passage to normally bias the valve to the first position and to move the valve to the second position when a vacuum is established in the intake passage. A further valve is diposed to control the connection and disconnection between the pressure responsive valve actuator and the intake passage.

Abstract: An exhaust gas recirculating device having a regulator integrally formed with an air horn of the carburetor, a throttle body and an insulator, both secured to a carburetor flange, a groove cut on the underside of the carburetor flange, a plate interposed between the flange and the suction manifold, said groove and plate forming an exhaust gas recirculating passage, a variable throttle valve, a throttle valve, and a link means interconnecting the variable throttle valve and the throttle valve, whereby exhaust gas from the engine is recirculated to downstream of the throttle valve. With this invention the exhaust gas recirculating device can be incorporated into conventional carburetors with minor modifications on the carburetor.

Abstract: An improved exhaust gas control apparatus, which utilizes a 3-way catalyst for reducing the contents of harmful components in exhaust gas, incorporates a diaphragm type air pump for supplying secondary air, upstream of the catalyst, to the exhaust gas. A chamber, which is formed on one side of the diaphragm in the air pump, is communicated through an electromagnetic changeover valve with the upstream side of the catalyst.

Abstract: A variable venturi type carburetor incorporating a changeover valve which conducts the fuel vapor in the float chamber either into the internal passage leading to the suction pipe of the carburetor or into the external passage leading to the canister. The changeover valve is actuated via a rod projecting into the intake passage by a suction piston which is displaced according to the amount of air drawn into the engine and which abuttingly contacts the rod. With this invention, an electromagnetic valve employed in the conventional carburetor can be obviated and the structure of the carburetor becomes simple and small.