Abstract: A pressure ratio valve is installed in an internal combustion engine having a pressurized air supply and an air actuatable throttle control means for limiting the engine RPM in response to a pneumatic control signal. The pressure ratio valve continuously senses both the engine oil pressure and the pressure of the engine compressed air system and generates the pneumatic control signal in response thereto. When the oil pressure-air pressure ratio decreases below a predetermined magnitude, an unsafe engine oil pressure condition is indicated and the pressure ratio valve generates a pneumatic control signal which causes the throttle control means to limit the engine RPM to a safe level.

Abstract: A pressure ratio valve is installed in an engine having an engine protection means for reducing the engine RPM to a safe level in response to an engine oil pressure below an acceptable level. The engine further includes a fuel pump for supplying fuel at a pressure linearly related to the engine RPM. The pressure ratio valve continuously senses both the oil pressure and the fuel pressure of the engine and reduces the engine oil pressure below the acceptable level of the engine protection means in response to a fuel pressure-oil pressure ratio in excess of a predetermined magnitude. This action by the pressure ratio valve causes the engine protection means to reduce the engine RPM to a safe level.

Abstract: A vacuum controlled timing system for an electrical accessory circuit of an internal combustion system having a variable vacuum source provides a uniform residual vacuum condition for maintaining a closed circuit for a selected time interval after the engine is rendered inoperative.

Abstract: An updraft carburetor of the type used on normally aspirated light aircraft engines and having a manually operable cable controlled mixture mechanism is provided with a biasing device which urges the mixture mechanism toward the full rich position to prevent engine failure in the event of cable failure.

Abstract: A device for controlling maximum speed and/or acceleration of a diesel engine by means of a spring-loaded valve located upstream on the air inlet manifold. The valve, which normally is open, operates on a pressure differential basis and is designed to close when maximum speed is exceeded. By sending the air flow rate to the engine, the air flow can be shut off when it exceeds a rate corresponding to an excessive engine speed.

Abstract: A variable position throttle stop and dashpot apparatus is shown as having a variably positionable throttle stop member having positions corresponding to and/or determining positions of engine idle throttle position and engine shut-down or anti-diesel throttle position with dashpot means effective for damping the rate of throttle closing movement regardless of whether the engine is operating or shut-down; resilient means are effective for moving the throttle stop member to a position for early engagement with linkage means associated with the throttle in order to thereby effectively damp the rate of closing movement of the throttle valve; and solenoid means is effective when de-energized to permit the throttle stop member to move to the anti-diesel position.

Abstract: A valve in the fuel line of an internal combustion engine of the type which is normally biased to its closed position, causing engine shut-down, but prevented by an opposing oil pressure from doing so; the valve, in effect, therefore being one which promotes engine shut-down in the event of failure in the engine oil pressure. As an improvement to this class of valves, of which the within valve is a significant contribution, the valve has an engine shut-down function related not merely to the required oil pressure at engine start-up, but also to required oil pressures at full power speed as well as intermediate power speeds throughout its contemplated range of operation.

Abstract: A system for reducing air pollutants expelled from a standard internal combustion engine coupled with an increase in fuel economy wherein a supplemental oxygen supply is introduced into the carburetor of an internal combustion engine while the fuel supply is reduced. The supplemental oxygen supply is regulated via a variable control valve and a safety shut off valve. The safety shut off valve is activated independently by both the engine ignition switch and one or more engine parameters which are only activated when the engine is in actual operation. This only allows oxygen to pass through the safety shut off valve when the engine is running and automatically stops the oxygen flow when the ignition switch is turned off or in case of inadvertent or accidental engine shut down.

Abstract: An exhaust temperature monitoring unit is provided with a thermocouple connected in opposition to a reference signal across the differential inputs of an operational amplifier. Both the thermocouple and the reference signal are connected to a common ground which is isolated from the vehicle chassis. This provides a floating reference point which is insensitive to variations in ground potential and eddy current in the vehicle chassis. The operational amplifier drives an optical coupling unit which in turn controls various alarms and vehicle controls.

Abstract: This invention provides means for stopping the flow of gasoline through a gasoline engine during the initiation of starting. In this way the engine contribution of smog forming materials is reduced and the engine is more easily started. This improved starting of the engine is achieved by increasing the portion of the work of compression available to usefully evaporate gasoline. To accomplish these results a stop valve is interposed between the fuel metering system and the fuel delivery jet of the engine carburetor, the valve being so automatically actuated so as to open only after a delay time interval of engine cranking during cold starting. The valve may also be closed automatically whenever the engine ignition is turned off thus assuring a prompt stopping of the engine.

Abstract: A solenoid actuated device to permit a carburetor throttle valve to close below the curb idle position upon deactivation of an ignition system for an internal combustion engine and to prevent electrical grounding by the device when it is out of contact with the throttle arm. The solenoid actuated device has an armature mounted in a housing for movement between energized and deenergized positions and a shaft extending through the housing is mounted within the bore of the armature for movement therewith. The shaft is in contact with the throttle arm adjacent one end and an electrical lead extends from the other end of the shaft. An insulating sleeve is positioned between the shaft and armature to prevent electrical grounding of the shaft when the shaft is out of electrical contact with the throttle arm. The insulating sleeve and shaft therein may be adjusted longitudinally relative to the armature to control the position of the throttle arm.

Abstract: The carburetor fuel bowl has a vapor vent hole closed by a manifold vacuum opened valve to prevent fuel spillage during vehicle rollover. During engine operation with low vacuum, the accelerator pump mechanically inhibits closure of the vent valve.

Abstract: A combined mechanical and electrical control for the traction drive and collector-impeller drive of a snowblower is provided which operates to disconnect the traction drive when the operator loosens his grip on a traction drive control lever to an extreme drive-disengage position to which it is constantly biased. Further, the control operates to stop the engine in the event that the operator loosens his grip on the level when the collector-impeller drive is engaged. However, the control is arranged such that the operator may manually hold the traction drive control lever in an intermediate drive-disengage position, while leaving the collector-impeller drive engaged without the engine stopping.

Abstract: The present invention relates to a regulating arrangement for metering a supplementary quantity of air for improving the combustion in internal combustion engines or afterburning of exhaust gases. The amount of air entering the regulating arrangement is metered as a function of the engine speed by means of an air pump driven by the engine. Part of the air entering the regulating arrangement is removed and returned depending on predetermined parameters. An auxiliary device responds to an emergency signal for the immediate shutoff of the fuel or fuel-air mixture used in the combustion. The emergency signal is transmitted by means monitoring the fuel-air ratio within substantially narrow tolerance limits of a predetermined threshold value.

Abstract: A device for slowing an internal combustion engine in the event of oil pressure failure at an engine speed above idle, includes an SCR with the gate thereof connected through a resistor to the field winding of the engine generator. The SCR is connected between an oil pressure sensing switch typically provided for the engine, and the ignition distributor points. Should the oil pressure switch close, indicating low oil pressure, and the engine is turning at sufficient speed so that the generator field provides enough voltage to the SCR gate, the SCR will fire and short the ignition.

Abstract: An audible enrichment bleed warning device, for fuel-injected engines having an enrichment bleed, emits an audible warning that the enrichment bleed is open and extra fuel is being delivered to the engine, reminding the operator to close it after the engine has warmed. The warning device may be a horn or a whistle.

Abstract: An ignition system of an internal combustion engine is provided with a hazardous-start inhibiting interlock that prevents the engine from being started unless an associated engine clutch, transmission, brake or similar device is placed in a safe condition for starting. The ignition system has a spark plug, a secondary winding of an ignition transformer connected to the plug to provide a sparking potential and a source of low-tension current pulses supplied to the primary winding of the ignition transformer in timed relationship with the engine cycle. The hazaradous-start inhibiting interlock is connected between the pulse source and the primary winding of the ignition transformer, and at the time of engine starting the interlock blocks the flow of current pulses to the primary winding unless the clutch, transmission or other device is safely positioned so that the vehicle or other mechanisms powered by the engine cannot be set in motion.

Abstract: The specification discloses a motor kill system for automatically shutting off and killing an internal combustion engine to prevent damage to the engine from obstruction of the air cleaning system. The motor kill system includes a vacuum switch operating in response to a drop in the pressure between the air cleaning system and the intake manifold of the engine caused by obstruction of the air cleaning system. The preferred embodiment of the invention utilizes a normally open vacuum switch that closes to cause a solenoid to operate a butterfly valve to cut off the air supply to kill the engine. An alternate embodiment of the invention utilizes a normally closed vacuum switch which operates in response to obstruction of the air cleaning system to open the circuit between the ignition and the fuel pump to cut off the fuel supply and thereby kill the engine before any damage is done.

Abstract: This is a valve for controlling the flow of fuel to an internal combustion engine in response to engine coolant temperature thereby preventing engine operation at full load above a selected coolant temperature.

Abstract: Disclosed is a safety interlock system for restraining certain kinds of movement of a chain saw throttle actuator. The system includes a stop member having an abutment portion for engaging the throttle actuator and a release portion projecting from a surface of the chain saw handgrip in position to be engaged by the hand of an operator gripping the handgrip. The stop member is rotatably mounted on the saw such that the movement of the stop member, as the release portion is depressed into a recess of the handgrip by the operator's hand, causes the abutment portion to swing away from interfering contact with the throttle actuator. Biasing means for the stop member maintain it in an orientation that prevents movement of the throttle actuator until the biasing force is overcome by the pressure of an operator's hand.The stop member can also include a lever portion and a hook portion, the latter engagable with a mating hook on the throttle actuator when that actuator is in an intermediate, or fast idle, position.

Abstract: An engine with an air vane type governor and provision for preventing overspeeding of the engine in the event the governor fails to do so, wherein a normally restrained or loaded spring acts to effect closing adjustment of the throttle valve upon release of its restraint by a tripping device actuated by a centrifugally projected plunger on the engine flywheel. In a modified embodiment, the release of the spring effects closure of an ignition grounding switch.

Abstract: An exhaust temperature monitoring unit including a thermocouple connected in summation with a regulated signal across the differential inputs of an operational amplifier to provide a temperature signal which is independent of the thermocouple ground. The operational amplifier drives a photocoupler at the output which in turn controls three functions. The first function provides an immediate audio alarm when a differential unbalance in the overheated direction is applied to the amplifier, the other two functions turning on a recorder and reducing fuel flow to the engine after a predetermined time delay.

Abstract: A sensing means is provided to monitor combustion of fuel and air supplied to an internal combustion engine, for example by sensing ignition pulses, combustion pressure, or cylinder temperature. Signals, as sensed, are compared and if one of these signals is extreme with respect to an average and, at the same time, the temperature of a catalytic reactor in the exhaust system becomes excessive, supply of the combustible fuel-air mixture to the specific cylinder is interrupted. To permit starting with unequal heating of cylinders, interruption of supply of the combustible fuel-air mixture is cancelled during starting, as sensed, for example, by closing of the starting switch, or low temperature in the engine system.

Abstract: An integral device for controlling the rate of throttle closure and for preventing after run of an internal combustion engine is provided which utilizes a pair of diaphragm assemblies for accomplishing both functional operations. The device includes a dash pot stem having an axial opening through it. The opening is operatively connected to a source of engine vacuum. A diaphragm housing defining a chamber has a pair of diaphragm assemblies positioned in it. A first diaphragm assembly is mounted to the dash pot stem. The second diaphragm assembly is movably mounted on the dash pot stem and includes a shaft extending through the housing. The shaft is engagable with suitable linkage means operatively connected to a throttle valve of a carburetor for the engine. Upon engine start, the application of engine vacuum to a first side of the first diaphragm operates on the diaphragm and housing so that, in effect, the housing moves in a first direction, positioning the shaft at its curb idle position.

Abstract: A monitoring and control apparatus for an engine, particularly a water-cooled internal combustion marine engine, which includes devices for monitoring the temperature and/or flow of the coolant liquid and/or of the lubricant, the monitoring devices being included in an alarm system adapted to give visual and/or audible warning of an abnormal condition and to reduce automatically the speed of the engine, in order to prevent or minimize the danger of damage thereto.

Abstract: A safety control method for limiting the temperature of a fluid to a given upper value comprising the sensing of the fluid temperature and the control of a servo-motor keyed in follow-up relationship to said temperature and acting upon a member controlling a parameter conditioning said temperature, wherein the improvement consists in the steps of effecting the detection so as to cause the displacement of a movable element through the expansion of a liquid heated up to a temperature varying in the same direction as the sensed temperature and transmitting said displacement through a hydraulic circuit relay to a hydraulic ram actuator forming said servo-motor.

Abstract: An alarm device for use in an exhaust gas recirculating system wherein part of exhaust gases from an internal combustion engine is introduced back into a suction system of the engine to thereby lower the combustion temperature of the engine, thus reducing the amount of nitric oxides contained in the exhaust gases. This alarm device is of the type which detects abnormal recirculating condition of recirculating exhaust gases to thereby warn of the abnormal operation of the exhaust gas recirculating system. The features of this alarm device are that the variation in flow rate of exhaust gases flowing through the exhaust gas recirculating passage communicating the exhaust gas system with a suction system is detected according to the pressure, whereby when the pressure thus detected deviates from the predetermined value, the abnormal-condition indicating device is driven to warn of the abnormal recirculation of exhaust gases.

Abstract: A solenoid operated valve is installed in the fuel supply line of an internal combustion engine and is effective to interrupt the flow of fuel to the engine while the operating solenoid thereof is energized. A normally closed contact pair of an electrical relay which is energized when the engine is in the normal cranking mode is connected in series in the energizing circuit of the operating solenoid of the solenoid operated valve. A holding circuit for the operating coil of the relay is provided and includes at least a normally open contact pair of the relay and circuitry responsive to the operating mode of the engine effective to interrupt the holding circuit while the engine is in the not running mode.

Abstract: The invention comprises a plurality of fluid actuated members for interrupting the ignition circuit and stopping the operation of an internal combustion engine in the event of a malfunction of the engine or components driven thereby. A tank containing air under pressure is connected with an electrical current conducting master switch interposed in the engine ignition circuit and comprising a hollow housing divided by a diaphragm which, by the tank air pressure, normally maintains the master switch closed. Loss of the air pressure opens the master switch. Other similar diaphragm type fluid pressure operated members respectively connected with and responsive to radiator coolant level and temperature, engine oil pressure and sprinkler system water pressure vents the pressurized air from the tank in the event of a malfunction.

Abstract: A safety device for an internal combustion engine with a liquid cooling system, in which the internal combustion engine is stopped by interruption of the fuel supply when the lubricating oil pressure drops below a minimum lubricating oil pressure corresponding to the prevailing load; the pressure of the cooling medium is thereby utilized as measuring magnitude for the load of the internal combustion engine.

Abstract: A throttle motion indicator device for an internal combustion engine of a vehicle having an induction system including a movable throttle for controlling flow through an induction passage and, an operator actuated accelerator pedal linkage, including a throttle rod, operatively connected to the throttle for controlling movement thereof, the indicator device including a spring positioned roller carried by the throttle rod in position to engage a detent means suitably positioned in the path of the roller as carried by the throttle rod to indicate to the operator a throttle position for improved fuel economy. With this device, the driver depresses the accelerator pedal until he feels a slight stiffening in the throttle movements which alerts him that he has reached a predetermined limit in acceleration rate to obtain good fuel economy. In an alternate embodiment, the detent means carries two detents to provide a signal to the operator of a range of throttle positions within an optimum acceleration range.

Abstract: An electric safety switch assembly for an internal combustion engine, the engine being provided with an oil pump to supply oil to a oil line for lubricating the engine, and an electric operated starter for the engine, including a manually operatable starter switch or closing an electric circuit to the starter and an electric circuit-breaker in the form of a oil pressure switch positioned between the manually operated switch and the starter which is normally held closed when there is no oil pressure in the oil line. The pressure switch is adapted to open the electric circuit when the engine is rotated sufficiently to cause the oil pump to produce a predetermined pressure in the oil line.

Abstract: A unitary device for controlling the rate of throttle closure and for preventing after run of an internal combustion engine is provided with simplified structure, the structure using a single shaft assembly for both functional operations. The shaft assembly is operatively connected to a diaphragm assembly which moves in response to forces acting to position the shaft assembly. The shaft assembly is an axially aligned and concentrically arranged combination, and includes a first shaft element which acts against the diaphragm assembly to bring a carburetor for an internal combustion engine slowly to its curb idle setting upon throttle release from some running condition. A second shaft element of the shaft assembly is controlled by a solenoid. The second shaft element acts against the diaphragm assembly upon ignition system de-energization, and permits the closure of the throttle below the curb idle setting of the carburetor.

Abstract: A low coolant level protection system for a vehicle having a radiator, an engine operated by a fluid fuel, a fuel source, and a conduit connecting the fuel source with the engine, the low water protection system including a probe extending within the radiator for conductive contact with coolant when the coolant is at proper operating levels, a voltage source, and a valve positioned in the conduit between the fuel source and the engine, the valve having an electric operated closure means in series with the voltage source and probe such that when the probe has continuity with the coolant in the radiator the value is actuated to an opened position allowing unrestricted flow of fuel to the engine, and when the continuity between the probe and coolant is lost, the valve closure member is moved to the closed position allowing only a preselected restricted rate of flow of fuel to the engine such that the operator may continue to operate the vehicle but at a greatly reduced rate of speed.

Abstract: Apparatus is disclosed which is useful for conserving fuel and which comprises a means for preventing or controlling the opening of a valve, commonly called a butterfly valve, of a carburetor, beyond a pre-selected point whereby the flow of fuel into the intake manifold is controlled. Disclosed more particularly is an improved gasket for insertion between the carburetor and intake manifold of a vehicle.

Abstract: An internal combustion engine is provided with an engine driven pump forced cooling system that is closed to permit operation at elevated pressures and temperatures. A protective device is provided to stop or otherwise modify normal engine operation upon a failure of adequate coolant flow. The protective device is made responsive to the difference in coolant pressure between the pump inlet and outlet to eliminate any effect of cooling system pressurization upon the indication of coolant flow. Variations in normal coolant flow with engine speed are accommodated by additional means responsive to pressure in another engine fluid system, such as the air box, where the pressure varies with engine speed, such that reduction of the differential coolant pressure across the pump below a predetermined value relative to engine speed permits actuation of the protective device to stop or modify engine operation.

Abstract: What follows is the description of a spring-loaded device for use in the fuel system of an internal combustion engine. The device includes a spring-loaded membrane connected to a valve which in turn provides access to atmospheric air. The arrangement is such that the danger of fuel escaping into the atmosphere or into the engine compartment is prevented.

Abstract: In a motor vehicle having a combustion engine including combustion spaces, such as pistons, comprising fuel dosing device, an exhaust gas conduit system and an exhaust gas cleaning arrangement associated with the exhaust gas conduit system, a temperature sensor provided in the exhaust gas cleaning system for producing control signals when the temperature of the exhaust gas cleaning system exceeds a predetermined value, the control signals being fed to the operating devices of the fuel and/or air dosing devices for at least reducing the fuel supply to the combustion engine.

Abstract: An anti-skid braking system which includes a throttle control arrangement associated with the throttle plate located in the induction manifold for opening the plate upon operation of the anti-skid system in order to compensate for the braking effect of the engine initiated upon release of the accelerator pedal. The throttle arrangement includes a solenoid-controlled vacuum actuator and a piston connected to the throttle plate through a lever system.

Abstract: A carburettor throttle member is provided with two return springs. The first spring is tensioned between the carburettor body and a disk rotatably mounted on the carburettor shaft. The second spring is weaker than the first spring and is compressed between the disk and shaft. The two springs tend to rotate the disk in opposite direction. The first spring normally retains the disk and shaft in a predetermined angular position. In case of fracture of the first spring, the second spring moves the disk into abutment with the fixed stop, operates as a substitute return spring.

Abstract: Alarm apparatus is provided for a recirculating exhaust gas flow control device, which device is employed in an internal combustion engine responsive to the negative pressure induced in the carburetor of the engine for controlling the flow of exhaust gas that is recirculated into the fuel-air mixture to be sucked into the engine; the device has a high pressure chamber in communication with the atmosphere, a low pressure chamber in communication with the engine negative intake pressure, and a diaphragm between the chambers for driving a valve that controls the flow of recirculating exhaust gas. The alarm apparatus employs a diaphragm forming high and low pressure chambers and for driving an actuating rod of a control circuit having an alarm signal lamp.

Abstract: An improved automobile engine carburetor in which a portion of the fresh air flowing into a carburetor main housing is bypassed through an auxiliary housing encasing a coiled bimetallic strip for controlling the position of a choke valve, so that the interior of the auxiliary housing may be maintained below a temperature at or above which the bimetallic strip may be heated to an unduly high temperature resulting in an earlier malfunction or failure.