Abstract: A throttle actuating device for an internal combustion engine of a soil compacting device, the internal combustion engine having a diaphragm carburetor and a connection between the fuel tank and the diaphragm carburetor, includes a control mechanism for switching the diaphragm carburetor into different operating positions including a full load position, an idle position, an intermediate position, and a turn-off position for the internal combustion engine. The intermediate position is located between the idle position and the turn-off position in the travel path of the control mechanism. The control mechanism, when being moved from the idle position toward the turn-off position, shuts off the connection 32 for interrupting fuel flow from the fuel tank to the diaphragm carburetor when passing through the intermediate position.

Abstract: A string trimmer with a control system for electric start, throttling, compression release, and engine kill control. An interlock is provided for preventing a start switch from being actuated unless the throttle trigger is fully actuated to a throttle fully open position. An idle setting system and engine kill button is provided at a control section at the throttle trigger. A single control cable is used for throttling, actuation of a compression release system at the engine, and stopping the operation of the engine.

Abstract: An emergency shut-off device for an air-compressing internal combustion engine is provided in the filter head of the engine fuel filter for the purpose of shutting off the fuel supply for shutting down the engine when the engine cannot be turned off by the ignition key.

Abstract: An engine has a carburetor that includes a bowl for fuel, a venturi in which the fuel is mixed with air, and a tube for carrying fuel from the bowl to the venturi. A solenoid valve is connected to the tube to control the flow of fuel to the venturi. An engine ignition system includes a coil assembly in which electricity is generated by a permanent magnet driven by the engine passing hear the coil assembly. A transformer includes a primary winding connected to the coil assembly, and a secondary winding. A storage capacitor and a diode are coupled in series across the secondary winding and a switch couples the solenoid valve to said storage capacitor. When an operator desires to stop the engine, the switch is closed which applies electricity from the capacitor to the solenoid valve to reduce an amount of fuel flowing through the tube.

Abstract: A device for stopping a diesel engine can properly control an engine stopping operation even if an engine rotation signal is not transmitted due to disconnection of a signal line at the time of the engine stopping operation and can prevent an engine stopping actuator from being burnt even if the engine does not stop due to mechanical trouble in a stopping mechanism. A contact 1a of a key switch 1 is turned from an ON terminal to an OFF terminal, whereby a transistor TR3 of a engine stopping operation section 8 us turned off. A transistor TR4 is turned on by a discharge of a capacitor C4, and a transistor TR5 and a relay switch 10 to follow are turned on to actuate a solenoid 11 to shut off fuel supply through a stopping mechanism.

Abstract: The control device enables an electrically triggered steering wheel key top and, in electronically controlled fuel injection pumps, provides a redundantly acting safety stopping device. For this purpose a 2/2-way valve is used as magnet valve (19), its switching state being determined by the position of the steering wheel key on the one hand and by a switching contact (16) of a diesel engine control device (17) on the other hand. The magnet valve (19) control the flow of engine lubricating oil to an operating piston (28) which can displace a control rod of the fuel injection pump, which controls the quantity of fuel delivered to the internal combustion engine, into its working area. The deflection of the operating piston (28) is influenced by a throttle (42) and a check valve (33), so that the control rod (44), after a stop position "O", automatically arrives in a start position "S" required for restarting the internal combustion engine.

Abstract: A fuel injection system including an arrangement for opening the injector valve after the engine has stopped so as to purge the injector of any accumulated fuel. The injection valve may be opened and closed through a number of repeated cycles which assist in the removal of carbon deposits or may be held open for a fixed time period. In addition, if the injector is of the air/fuel type, any compressed air in the chamber can be utilized to purge the fuel and also the opening of the injection valve will preclude the accumulation of air pressure in the system after the engine has been shut down.

Abstract: An anti-after-burning system in an internal combustion engine provided with a governor device, in which a governor spring is stretched between a governor lever and a governor control lever and the governor lever is connected to a carburetor throttle lever, and a stoppage device for stopping an engine by grounding a primary wire of an ignition circuit, is improved. The governor control lever is provided with a grounding section for grounding the primary wire of the ignition circuit as a result of the rotation of the lever to an engine stoppage position. The governor lever and one end of the governor spring are connected so as to be relatively rotatable and so as to have a freedom of movement with respect to the axial direction of the governor spring.

Abstract: An arrangement for controlling fuel flow to an internal combustion engine includes a fuel-injection pump, a fuel tank, and a mechanically driven pre-supply pump for supplying fuel from the fuel tank to the suction space of the fuel injection pump. An electromagnetic control valve located downstream of the pre-supply pump and upstream of the suction space of the fuel injection pump moves between a supply position in which fuel flows from the pre-supply pump into the suction space, and a disconnect position. A mechanically driven additional suction supply pump communicates the suction space with the fuel tank in the disconnect position of the electromagnetic control valve. The electromagnetic control valve has throttle means for communicating the suction space of the fuel injection pump with the inlet of the additional suction supply pump in the disconnect position of the electromagnetic control valve.

Abstract: There is provided a diesel engine shut-down device for stopping a diesel engine by actuating an engine shut-down mechanism with an actuator when an engine key switch is turned off. The device comprises a key switch detector for detecting the ON/OFF state of the key switch and for producing an engine stop signal when the key switch is in the OFF state, a rotation detector responsive both to the engine stop signal for detecting a rotation state of the engine so as to produce an actuator drive signal when the engine is rotating, an actuator driver responsive to the actuator drive signal for driving the actuator and a timer for stopping the production of the engine stop signal when a predetermined period of time elapses after the key switch is turned off, to stop the actuator after elapsing of the predetermind period of time even if the engine is not stopped though the actuator has operated.

Abstract: The shut-down device stops a diesel engine by cutting the fuel supply or the intake air supply. The device comprises a timer having a capacitor which outputs engine stop signals for a predetermined time when a key switch is turned off, and a drive element having a switching device which supplies an actuator for stopping the engine with operation signals in accordance with the engine stop signals from the capacitor. The switching device includes an NPN-type transistor to receive the engine stop signals as a base voltage and to be connected to a starter of the engine, and a PNP-type transistor to receive a divided voltage from a battery in accordance with the starter operation and to output the operation signals to the actuator.

Abstract: An accelerator pedal position signal is transmitted by wire to the electronic control unit which operates a unipolar stepper motor to position the throttle in correspondence with the position of the accelerator pedal. A circuit of the electronic control unit monitors the response of the throttle to the release of the accelerator pedal and to the operation of the brake pedal in such a manner that unless the throttle is at, or at least within a predetermining distance of, its idle position within a certain limited time after the commencement of concurrence of accelerator pedal release and brake pedal application, the engine is shut down.

Abstract: The shut-down device stops a diesel engine by cutting the fuel supply or the intake air supply. The device comprises a timer having a capacitor which outputs engine stop signals for a predetermined time when a key switch is turned off, and a drive element having a switching device which supplies an actuator for stopping the engine with operation signals in accordance with the engine stop signals from the capacitor. The switching device includes an NPN-type transistor to receive the engine stop signals as a base voltage and to be connected to a starter of the engine, and a PNP-type transistor to receive a divdied voltage from a battery in accordance with the starter operation and to output the operation signals to the actuator.

Abstract: A dashpot has a diaphragm provided for defining a pressure chamber and an atmospheric chamber, and an actuating rod secured to the diaphragm and operatively connected to a throttle valve. A cylindrical supporting member is secured to the diaphragm, opposite to the actuating rod, and a spring loaded valve is provided on an end of the cylindrical supporting member. A pipe secured to the dashpot body and having an opening at an end thereof, is projected into the pressure chamber. The opening is disposed to be closed by the spring loaded valve when the diaphragm is deflected by the throttle valve. A solenoid operated valve is provided to communicate the pressure chamber with the atmosphere through the pipe when opened. the diaphragm and the spring loaded valve are arranged such that the spring loaded valve closes the opening of the pipe at a smaller stroke than that of the diaphragm.

Abstract: A positioning device comprising a solenoid, said solenoid having a plunger slidable upon energization of the solenoid, a solenoid stop associated with said solenoid, a stem operatively connected to said plunger and extending through the movable stop to the exterior, an actuator connected to said solenoid stop and operable to move said stop to selected positions, such that when the solenoid is energized, the plunger is moved to engage the stop and move the stem to a predetermined position, the extent of movement being determined by actuation of the actuator to move the stop in predetermined positions.

Abstract: An anti-dieseling structure for demand carburetors wherein the air valve of a particular demand carburetor is provided with an exteriorly actuated lift lever, the same, when hand actuated, operates to lift the air valve. The tapered metering needle depending from the mechanically raised air valve is to make the fuel air mixture progressively more lean, with a carburetor operating at idle condition, to thereby starve the engine as to fuel intake and thus cause the engine to shut off in a positive manner and thus avoid dieseling. One or more carburetors may be accommodated by respective levers; where plural carburetors are employed, the levers are keyed to a common shaft that is rotated by control means leading to the dashboard at the driver's compartment. The engine, of course, will operate in the usual manner when the control cable coupled to the levers is not actuated, thereby leaving the air valves free to operate in the usual manner.

Abstract: A throttle positioning device comprising a housing and a diaphragm in the housing dividing the housing into first and second chambers. The housing has an opening extending to the first chamber for connection to vacuum. A solenoid is associated with the housing and has a plunger acted upon by energization of the solenoid. The plunger is yieldingly urged by a light spring against a solenoid stop connected to the diaphragm such that the stop is movable with the diaphragm. A stem is adapted to be moved by the plunger and extends through the movable stop to the exterior of said housing to define a movable throttle stop. The throttle lever, attached to the throttle shaft of the carburetor yieldingly urges the throttle stop to a retracted position against the lighter spring force of the solenoid plunger. The diaphragm is yieldingly urged to move the movable solenoid stop toward the solenoid.

Abstract: Throttle valve control apparatus including an idle-speed increasing device for causing the throttle valve to open beyond the normal idle position according to engine load, a valve closing device for permitting the throttle valve to close beyond the normal idle position when the engine is decelerating or the like, and a restraining mechanism for restraining the operation of the idle-speed increasing device during operation of the valve closing device.

Abstract: Apparatus and method for expediting the starting of an internal combustion engine in which a vacuum-operated throttle actuator is controlled by a vacuum passage connected therewith and extending from an intake vacuum outlet located adjacent to the throttle valve. According to the invention, a second vacuum passage to the actuator communicates with the intake duct downstream of the throttle valve and a solenoid type switching valve is arranged between the two vacuum passages so that, when a warmed engine is restarted, the actuator is fed with vacuum through the second passage to actuate the throttle valve to a more open position than its normal idling position to yield a mixture of optimal air fuel ratio.

Abstract: An emergency air shutdown system for diesel engines which has air intake manifold and curved discharge tubes leading into the manifold for a plurality of cylinders, the system comprising a valve member for each discharge tube and pivotal mounting means therefor to cause movement of the valve member about an axis substantially parallel to the air flow through the discharge tube between an open position outside the path of air flow and a closed position across the tube to block the air flow. Locking means are provided for keeping the valve in an open position, and activating means are provided to effect release of the locking means so as to permit rapid movement to the closed position across each tube.

Abstract: An air valve type two-stage twin compound carburetor for an internal combustion engine comprises a carburetor body including a primary bore and a secondary bore, a primary throttle valve which is arranged in the primary bore so that it can be opened and closed, a secondary throttle valve which is arranged in the secondary throttle bore so that it can be opened and closed co-operatively with the opening and closing of the primary throttle valve after the primary throttle valve has been opened beyond a certain degree, and an air valve which is arranged in the secondary bore upstream of a secondary fuel nozzle disposed upstream of the secondary throttle valve, so that the air valve is opened and closed. The degree of opening of the air valve is regulated so as to be opened when the primary throttle valve is in the idle closing position or in the initial opening position.

Abstract: The control circuit and apparatus is used and utilized with and by internal combustion engines that employ injector pumps for delivery of fuel to cylinders. Usually this arrangement includes metering and often the engine is a diesel engine. The fuel is delivered at a given flow rate which is in excess of the required flow and this excess is returned through a return conduit to a supply tank. The invention provides for electrically actuating apparatus for effectively terminating the supply of fuel to the injector pump. Five circuit arrangements are depicted, a first arrangement includes a solenoid actuated valve in the supply line and an electrically actuated return flow pump in the return line. A second arrangement has a return flow pump in the delivery line with the return flow pump, when actuated, having a greater flow capability than the transfer pump. A third arrangement employs two electrically actuated three-way valves and associated by-pass conduits in the delivery line.

Abstract: A stopping device for an engine supplied with fuel by a fuel injection pump including a change-over valve, and an actuator for actuating the change-over valve in response to an engine shutdown operation. The change-over valve is movable between a first position to which it moves at engine startup to connect a fuel tank with an inlet of a fuel supply pump driven by the engine and connect an outlet of the fuel supply pump with an inlet of the fuel injection pump, and a second position to which it moves in response to an engine shutdown operation to connect the inlet of the fuel injection pump with the inlet of the fuel supply pump and connect the outlet of the fuel supply pump with the fuel tank.

Abstract: A gas-operated internal combustion engine which includes a volume control valve for a gas supplied to an air/gas mixer. An air filter is arranged within a charged air supply arrangement and, between a diaphragm of the volume control valve in a section of the air charge supply, a pressure equalizing connection is provided which, starting from the air filter or from the air/gas mixer and extending in a direction toward the volume control valve includes a throttle and a blocking biased check valve. A conduit branches off in the pressure-equalizing line at a point between the air filter and the check valve, with the conduit leading through a diaphragm operated valve to the intake manifold. The valve is controllable by the intake manifold vacuum such that the conduit is blocked with a high value intake manifold vacuum and opened with a low value intake manifold vacuum.

Abstract: A positioning device for an air valve arranged in the charging air line of a diesel engine, particularly charged by means of a pressure wave-charging device. The air valve or flap is provided with a shutoff valve incorporated into the flow path between an impingement line branching-off from a pressure oil line of the diesel engine and an oil return flow line. The impingement line is connected with an impingement chamber for a positioning piston actuating the air valve or flap. The positioning piston is loaded by a continuously effective force and the shutoff valve is actuated, in order to impinge the positioning piston with oil, in the opening direction of the air valve or flap by a control piston loaded by the pressure in the air charging line against the force of a spring.

Abstract: An internal combustion engine includes an intake system and an exhaaust system, and an exhaust gas recirculation conduit leads from the exhaust system to the intake system for recirculating exhaust gas. An exhaust gas recirculation control valve at an intermediate part of the exhaust gas recirculation passage controls the flow of exhaust gases therein, and is operated by supply of actuating vacuum. The supply of actuating vacuum to the exhaust gas recirculation control valve is furnished according to engine operational conditions. A vacuum tank accumulates vacuum while the engine is running. A vacuum conduit joins the vacuum tank to the exhaust gas recirculation control valve, and is controlled by a vacuum valve which is closed when the ignition system of the engine is being supplied with electrical power, and is open when the ignition system is not being supplied with electrical power.

Abstract: A throttle valve opening controller for applying variable retarding forces against the closing force of the throttle valve at the time of quick closing thereof depending on the running condition of the engine, comprising: a diaphragm device consisting of a diaphragm which is movable in association with the throttle valve when the throttle valve opening is smaller than the specified value, a spring for urging said diaphragm with a force smaller than the closing force of the throttle valve, and a diaphragm chamber which is formed on the rear side of said diaphragm and to which atmospheric pressure or intake vacuum immediately downstream of the throttle valve is admitted; and means for varying the leak rate of the air discharged from the diaphragm chamber of said diaphragm device at the time of quick closing of the throttle valve depending on the running condition of the engine.

Abstract: A method and apparatus for shutting off liquid flow such as fuel in a carburetor during certain sensed conditions, in which an adjustment is provided for further controlling the liquid at times when the liquid is not shut off. When used on a carburetor, idle fuel or injection water is shut off by a needle valve. The needle valve may be retracted to an "on" position. The "on" position is adjustable so as to provide a flow adjustment. Such an arrangement may be provided as an original design feature of a carburetor or may be added to existing carburetor designs, for example, as a kit.When used as an idle fuel shut-off, the needle valve is adjusted in the "on" position in a manner similar to conventional idle mixture adjustment using idle mixture adjusting screws. Thus, fuel in the idle circuit may be interrupted during engine deceleration, as detected by a high manifold vacuum condition, or during engine shut-off, as detected by an interruption in the engine's ignition circuit.

Abstract: Disclosed herein is an improvement in a variable venturi carburetor for an internal combustion engine which comprises a venturi portion, a float chamber, a main fuel passage communicating with the venturi portion and with the float chamber, a main jet provided in the main fuel passage and a movable metering needle of which free end is adapted to control the size of the main jet and the base portion thereof is mounted to a suction piston adapted to transversely move with respect to the venturi portion in response to the condition of load on the internal combustion engine. The improvement includes provision of a fuel bypass which detours the main jet for supplying part of fuel to the venturi portion. The fuel bypass communicates with the atmosphere through one or more throttles.

Abstract: A multi-stage latching device for a carburetor which controls the idle speed by defining various throttle plate positions according to deceleration sensor switch, air conditioning switch and ignition switch states. The mechanism which moves the throttle plate consists of a primary force coil which energizes an armature against spring return and the position of the armature coupled through a shaft establishes the idle speed. The throttle position is determined by any one of three adjustably disposed latch coils which when energized, magnetically couple to a casing to define a stop. A circuit control associated with each latch deenergizes the primary force coil while maintaining the magnetic coupling of the stop. With primary force off, the return spring forces the armature back against the energized stop and hence establishes the throttle position and idle speed.

Abstract: A diesel engine fuel supply and control system for an engine having a fuel supply pump which has its direction of rotation in accord with the direction of engine rotation is provided with engine shutdown, anti-bump start and reverse rotation arresting means including, in a preferred embodiment, a pressure responsive piston that acts against a run-stop control lever to cut off fuel supply to the engine cylinders and a selector valve that selectively exposes the piston to pressures on either side of the engine fuel pump. When the valve is set to provide the normal pump inlet pressure to the piston, the engine may operate in the forward rotation direction but is stopped if reverse rotation occurs. If changed to expose the piston to normal pump outlet pressure, the engine is stopped or prevented from operating in the forward rotation direction.

Abstract: A gas-operated internal combustion engine which includes an air/gas mixer and a volume control valve for feeding gas to the air/gas mixer. The volume control valve is normally biased into a closed position and includes a diaphragm adapted to be exposed on an operating side thereof to a vacuum ambient in the gas downstream of the volume control valve so as to urge the diaphragm to opening position of the volume control valve. A rear side of the diaphragm is adapted to be exposed to a control pressure. A pressure compensating connection is provided between the rear side of the diaphragm and a portion of the air supply system of the engine and terminates at or upstream of the air/gas mixer. A choke is arranged in the pressure compensating connection at either an air filter of the air supply system or a housing of the air/gas mixer with a check valve being disposed in the pressure compensating connection at a position between the choke and the volume control valve.

Abstract: Disclosed is a carburetor for internal combustion engines having mechanism substantially to eliminate the effect on the engine of carburetor ice. When ice builds on the downstream face of the butterfly valve, on the side adjacent the idle jet, there is such a reduction of pressure at the mouth of the idle jet as to cause fuel starvation in the main jet, thus causing improper fuel air ratios or engine failure. To overcome this, mechanism is provided to vent the idle jet passage to atmosphere whenever the butterfly valve is in position for the main jet to become the primary source of fuel supply. Further, by venting the idle jet as indicated, the presence of ice on the butterfly valve will not produce the heretofore over-rich or lean mixtures, found to exist. Furthermore, such venting is useful for preventing dieseling in automobile engines.

Abstract: A circuit for actuating control elements, for example a fuel shutoff valve in the carburetor of an internal combustion engine or a similar control element. The circuit is responsive to engine speed and to throttle valve position as monitored via the intake manifold vacuum. When the engine idles and the throttle is closed, the fuel control valve is held open to supply normal idling fuel or fuel mixture. However, if the engine speed rises above a threshold speed while the throttle is closed, the control circuit assumes a condition of engine braking and the fuel supply is interrupted. The switching threshold is established as the voltage on a capacitor controlling a transistor, the capacitor being charged continuously and being discharged during the occurrence of voltage spikes taken from the ignition coil of the vehicle.

Abstract: A vacuum operated servo comprises a vacuum chamber defined by a flexible diaphragm and a cover, a valve seat secured to the cover so as to project into the vacuum chamber, a valve body yieldably mounted on the flexible diaphragm, a first vacuum conduit with a first valve for inducing vacuum from a vacuum source into the vacuum chamber through the valve seat, a second vacuum conduit with a second valve for inducing vacuum from the vacuum source into the vacuum chamber, and a leak orifice for leaking the vacuum in the vacuum chamber. When the first valve is opened to induce vacuum of the vacuum source into the vacuum chamber, by the vacuum, the diaphragm is moved so that the valve body contacts with the valve seat. Upon the contact, the induction of the vacuum is interrupted to stop the movement of the diaphragm, with the vacuum being introduced and leaked out of the vacuum chamber.

Abstract: Apparatus for controlling fuel supply to an internal combustion engine includes means for interrupting the fuel supply, which means includes two devices operable independently of engine operating conditions. One of the devices is operated when a given engine speed and/or a given vehicle speed is exceeded with engine fuel supply regulating means in a no supply condition. The other of the devices is operated when a predetermined vehicle speed is exceeded.

Abstract: The apparatus according to the present invention includes means for conducting secondary air into the exhaust lines of a multi-cylinder internal combustion engine, which conducts the secondary air into exhaust passages for one or more of the cylinders, and means for conducting a requisite amount of atmospheric air into the intake lines of the all or a part of the cylinders being available for said secondary air conduction, in response to an abrupt change of the negative pressure in the intake pipe through a mixture control valve.

Abstract: Control system for a secondary transfer port in a dual carburetor used for an internal combustion engine, which control system opens the secondary transfer port by a magnet valve connected electrically to an ignition switch during the high-load operation of the engine and closes the secondary transfer port by the magnet valve during the low-load operation of the engine.

Abstract: An idle speed control actuator is used to maintain a constant vehicle engine idle speed in response to variations of the load on the vehicle engine. The actuator responds almost immediately to an increase in the load on the engine to prevent the engine from stalling, but reduces idle speed slowly when the load on the engine is reduced during idle conditions or when the throttle control lever is returned to the idle position so that the actuator does not have to "hunt" for the proper engine idle speed. The actuator includes a control plunger which is engaged by the throttle lever when the latter is returned to its engine idle position, so that the position of the throttle lever, and, accordingly, the opening of the carburetor butterfly valve which sets the engine idle speed, is varied in accordance with the position of the plunger.

Abstract: A dashpot with a fast idle device for carburetor throttles comprises a dashpot for damping a rapid closing movement of the throttle and a fast idle device for causing an automobile to run at fast idle. The fast idle device has a vacuum chamber separated from an air chamber of the dashpot by a partition, and a rod passing through a hole made in the partition, which rod is secured to a diaphragm defining a part of the vacuum chamber and axially moved with vacuum induced into the vacuum chamber.

Abstract: A diesel engine fuel control apparatus is disclosed wherein a control unit for controlling the amount of the supply of fuel by a key switch which selectively connects a start position terminal, a normal position terminal and an interruption position terminal to a power supply, includes a control lever position sensing switching means for controlling a fuel injection pump and switchover means which are connected to at least the start position terminal and the normal position terminal, respectively, to control the energization of an actuator of a pump control lever, and a normally closed switching means which is turned off when an exhaust brake is applied is connected between said normal position terminal and one of said switching means.

Abstract: An internal combustion engine for an automobile provided with an air conditioner which has an electromagnetic clutch capable of connecting the crankshaft of the engine with a compressor of the air conditioner. A switch mechanism is provided for engaging the clutch just after the ignition switch is opened to effectively brake the rotation of the crankshaft due to inertia by using a load of the compressor. Thus, the so-called "dieseling" can be prevented.

Abstract: Disclosed is a butterfly valve opening degree setting device comprising a diaphragm apparatus. The diaphragm apparatus has a diaphragm, a vacuum chamber and a control rod connected to the diaphragm. The control rod is arranged so as to be engageable with the butterfly valve disposed in the duct. The vacuum chamber of the diaphragm apparatus is connected to the vacuum port formed on the inner wall of the duct. The butterfly valve is held open at a position wherein the peripheral edge of the butterfly valve faces the vacuum port.

Abstract: An electrical circuit for use with an engine having an alternator has a relay to control a solenoid to properly shut down a diesel engine and includes openable and closable contacts for supplying power to another portion of the circuit, it being ensured that such contacts remain closed when either the vehicle key is in the on position or there exists an alternator output.

Abstract: A system for controlling or interrupting the fuel supply in an internal combustion engine operating under a braking condition, in response to the vacuum level in its intake system. This system is equipped with an air pump driven by an output shaft of the engine, and a pressure responsive valve including two chambers partitioned by a diaphragm, a valve body coupled to the diaphragm and a valve seat therefor. A discharge pressure from the air pump is applied to one of the chambers, and a vacuum from the intake system, downstream of a throttle valve in the carburetor, is applied to the other of the chambers. This pressure responsive valve readily discriminates between the engine braking condition and the idling condition of the engine, by widening the sensible or detecting range between the maximum possible vacuum level in an intake pipe, upon idling and the minimum possible vacuum level in the intake pipe, upon engine braking.

Abstract: A throttle valve operating mechanism according to the invention has two functions one of which is a dashpot function to dampen the closing rotation of the throttle valve of the carburetor thereby achieving reduction of harmful compounds such as HC and CO contained in the exhaust gases from the internal combustion engine during deceleration of the same and the other of which is to open the throttle valve by a predetermined amount from the initially set nearly closed position when an engine driven power consuming device such as air-conditioner compressor starts to run during idling of the engine. This throttle valve operating mechanism is very compactly made by employing integrated construction.

Abstract: Communication between a low-speed circuit and a main circuit of a carburetor is cut off when the engine is operated at high engine speed and load.

Abstract: Apparatus for controlling fuel flow to an engine including means for disabling the operation of the accelerator pedal linkage associated with a carburetor is disclosed. The construction materially aids in preventing engine backfire. Included is a pivotable solenoid operated latch plate which forms part of an essential pivot point in the linkage arrangement and fixes the pivot point when current is flowing from the coil in engine ignition circuit.Solenoid operated means for stopping fuel to the carburetor and closing the passageway from the carburetor into the intake manifold are also shown.

Abstract: Disclosed is an exhaust gas recirculation apparatus for an internal combustion engine, which has a vacuum operated flow control valve arranged on pipe means connecting the exhaust manifold of the engine with the intake manifold of the engine. When the throttle valve is opened from its idle position during the operation of the engine, the flow control valve is opened in order to recirculate exhaust gas from the exhaust manifold to the intake manifold. The apparatus further has means for opening the flow control valve when so-called "dieseling" takes place after the operation of the engine is stopped. The exhaust gas due to the dieseling can be recirculated and, thus, the dieseling is instantly stopped.

Abstract: A carburetor having a venturi constriction within an air passage leading to the engine intake manifold, a fuel bowl with a discharge nozzle for delivering fuel to the venturi constriction, and a bowl vent passage between the fuel bowl and a position at atmospheric pressure, includes a duct communicating between the venturi constriction and the fuel bowl. A solenoid valve is disposed in the bowl vent passage and is operatively connected to the ignition; the valve is open when the ignition is turned on so that the fuel bowl is exposed to atmospheric pressure allowing the nozzle to discharge fuel into the venturi constriction, and it is closed when the ignition is turned off. With the valve closed, the pressures in the venturi constriction and the fuel bowl are equalized preventing the flow of fuel through the nozzle to the venturi constriction and inhibiting "dieseling" after ignition shut-off.