Abstract: An intake system has a recirculation passage, through which supercharging air discharged from a supercharger is recirculated into the supercharger, and a recirculation control valve disposed in the recirculation passage, by which the recirculation passage is gradually opened and closed as the pressure of supercharging air downstream from the supercharger changes between a low specified pressure, below the atmospheric pressure, and a high specific pressure, above the atmospheric pressure. The air intake system further has a bypass passage, for allowing air to bypass an intercooler, which is opened and closed by a bypass control valve at an interim specified pressure between the high and low specified pressures.

Abstract: An apparatus and method for controlling the boost pressure of air delivered to a gas fuelled internal combustion engine from air compression means such as a turbocharger. An engine management system (EMS) controls a spark ignition system as well as a gas delivery system for controlling the delivery of gaseous fuel to a fuel inlet. Air is delivered to the engine through air inlet via air throttle means which is also under the control of the EMS. Boost pressure is controlled by an exhaust control valve which is operative to direct a proportion of the exhaust gases to turbocharger. The amount of compression of the air depends on the proportion of the exhaust gases diverted to the turbocharger, which is variable when the engine is operating on gaseous fuel under the control of EMS.

Abstract: Device for injecting air into an exhaust system fitted with catalytic cleaner for a supercharged Otto engine, in whose intake manifold is incorporated a motor driven air compressor operating with internal compression, giving rise to the supercharging. An air bleeding duct is arranged for adjustable air bleeding from the constriction zone of the air compressor to supply this air as additional air to the catalytic cleaner. This air bleeding duct extends from a point in the constriction zone to a point in the exhaust system upstream from the catalytic cleaner. In an inlet section of the intake manifold, located upstream from the compressor, is installed an electronically controlled device for engine idle control during bleeding of the air via the air bleeding duct.

Abstract: A device for injecting air into an exhaust system fitted with catalytic cleaner for a supercharged Otto engine, in whose intake manifold is incorporated an air compressor driven by the engine, which compressor causes the supercharging. An air bleeding duct is arranged for adjustable bleeding of air from the intake manifold and to supply this air as additional air to the catalytic cleaner. This air bleeding duct extends from a point in the intake manifold downstream from the compressor to a point in the exhaust system upstream from the catalytic cleaner. In an inlet section of the intake manifold, located upstream from the compressor, there is an electronically controlled device for idle control of the engine as the air is bled via the air bleeding duct.

Abstract: A supercharging pressure control device for an engine having a supercharger, which is driven by the engine and disposed in an intake passage downstream of an engine throttle valve, includes a bypass passage. The bypass passage connects a part of the intake passage, upstream from the supercharger and downstream from the engine throttle valve, and a part of the intake passage downstream from the supercharger. A bypass valve is disposed in the bypass passage. The bypass valve is controlled so as to allow intake air to bypass the supercharger at a controlled flow rate.

Abstract: The body of the proposed axial piston machine incorporates a cylinder block ith cylindrical spaces. The axes of the cylindrical spaces are parallel with the longitudinal axis of the engine crankshaft and the cylindrical spaces accommodate reciprocating pistons. Each piston is connected to one end a rod. The other end of the rod is articulated with the swash plate, which is mounted via a first support, on the inclined journal of the shaft installed on supports in the body and which is articulated to the body by universal joints. The machine of the invention provides a second spherical support for the swash plate. The second support is connected with the frame and the center of the support is essentially aligned with the geometric center of the connecting member of the universal joints. The bisector plane which is the plane of symmetry of the universal joints passes through the center of the support.

Abstract: A 7-cylinder axial-piston internal combustion engine has a casing (33) inded for connection with a cylinder block (2). Formed in the casing (33) coaxially with shaft (11) is a cavity which receives a drive gear 41 on an end of the shaft (11). The drive gear (41) is in mesh with a gear wheel (42) installed in the casing (33) and kinematically connected to a ring-shaped member (68) having external radial projections (71, 72) and an internal ring gear (83). The member (68) is kinematically connected to actuating members. A zone A of engagement of the drive gear (41) with the gear wheel (42) communicates with a header (54) for oil supply. A zone B outside the engagement of the drive gear (41) with the gear wheel (42) communicates with a source of lubrication.

Abstract: A supercharger system for an internal combustion engine in a vehicle driveline that includes a catalytic converter for oxidizing undesirable exhaust gas emissions including a single, dual-purpose air pump for establishing combustion airflow for the engine as well as for the catalytic converter including an automatic control valve system having an electronic microprocessor that monitors varying engine operating conditions for establishing optimum airflow for fuel combustion purposes and for oxidizing exhaust gas emissions throughout a range of operating conditions for the engine, the system including a variable ratio mechanical drive between the engine and the air pump.

Abstract: A control system and method for governing turbocharged internal combustion engines is disclosed including an electronic control unit, a fuel flow control valve, an engine speed sensor, and a bypass valve to control exhaust gas flow through an exhaust bypass conduit. When engine speed is above a first predetermined engine speed, the electronic control unit controls the bypass valve to regulate exhaust gas flow through the bypass conduit, thereby limiting exhaust gas flow through the turbocharger. When the engine speed reaches a second, predetermined engine speed value that is higher than the first predetermined engine speed value, the electronic control unit completely opens the bypass valve allowing virtually total bypass of the turbocharger, and limits fuel flow to the engine by controlling the fuel flow control valve.

Abstract: An internal combustion engine and method for operating the engine wherein a leaner than stoichiometric air/fuel ratio is maintained under all running conditions. The desired torque curve is obtained by increasing the amount of boost generated to the intake air charge without enrichening the air/fuel mixture. In addition, an anti-knocking system is incorporated that avoids knocking by retarding the spark advance and, at the same time, providing a leaning in the air/fuel mixture.

Abstract: Arrangements are disclosed for a highly improved pivoting slipper pad bearing construction offering a reduction in friction, an increase in efficiency and by virtue of their shape and simplicity of form, may be easily and inexpensively produced. Also a superior crosshead mechanism for swashplate engines, pumps and compressors that features a unique lubrication arrangement that assures low friction and long life.

Abstract: The combination of an intake air supply system with an internal combustion engine having a charge air cooler, a cylinder charging air intake and an exhaust discharge is provided. The intake air supply system includes a Roots-type positive displacement blower having inlet and outlet means and an exhaust gas driven turbo-compressor connected in series with the blower. The intake air supply system further includes a bypass passage connecting the blower inlet and outlet and a valve in the bypass passage to control the flow of fluid through the bypass. The valve is operative to open and close the bypass passage in response to engine operating parameters and to modulate the flow area of the passage in response to the same engine operating parameters so as to infinitely vary the flow area between the open and closed positions of the valve.

Abstract: A system for controlling the supercharge pressure in an internal combustion engine having a mechanical supercharger which is connected to the crankshaft of an engine and includes a variable compressing construction capable of varying the internal compression ratio. The system comprises a supercharge pressure varying assembly for varying the supercharge pressure, a detector for detecting the operational condition of the supercharge pressure varying assembly, and a control device for operating the supercharge pressure varying assembly into a supercharge pressure reducing position in response to the detection, by the detector, of the fact that the supercharge pressure varying assembly is in a low level compressing state in an operational condition of the engine in which the mechanical supercharger should be brought into a high level compressing state. Thus, even if an abnormality occurs in the variable compressing assembly, an increase in the temperature of the intake gas in the engine is prevented.

Abstract: A supercharging pressure control system for supercharged internal combustion engines includes a supercharging pressure control valve for controlling supercharging pressure of intake air, supplied by a supercharger. A desired value of the opening of the supercharging pressure control valve is determined depending on operating conditions of the engine. When the supercharging pressure detected has reached the desired value of the supercharing pressure, a feedback control mode is selected, in which the opening of the supercharging pressure control valve is controlled so as to make the supercharging pressure detected equal to the desired value of the supercharging pressure.

Abstract: A boost pressure control system for a vehicle engine equipped with a supercharger and a torque converter having a lock-up clutch, in which the boost pressure is controlled by adjusting the degree of the opening of an air bypass valve and the ON/OFF position of the supercharger in such manner that the different control characteristics of the boost pressure are selected in accordance with whether the lock-up clutch of the torque converter is turned ON or OFF, i.e., when the lock-up clutch is turned ON, the supercharger is started at a lower engine load, and the degree of the opening of the air bypass valve is set smaller, thereby enabling the lock-up operation of the torque converter under running conditions in which a higher driving torque is required and, thereby widening the operating range of the lock-up operation of the torque converter and improving the fuel economy of the vehicle.

Abstract: Several embodiments of turbocharged internal combustion engines wherein the turbocharger is designed to provide high boost at low and mid range and the boost is reduced at high range to maintain either a limitation of the maximum boost or to maintain the boost pressure in a linear relation to engine speed. The means for reducing the boost pressure comprises a throttle valve in the induction passage that is operated in a variety of manners responsive to engine speed.

Abstract: In an intake air flow increasing device for a combustion engine according to this invention, an air exhausting body is provided forward of an air intake opening, and the air exhausting body is connected to a main compressed air conducting path and an auxiliary compressed air conducting path, while each of the compressed air conducting paths is connected to an air compressing mechanism via a main switching control valve and an auxiliary switching control valve respectively. The main switching control valve is opend and closed according to switching operations of a speed change mechanism when a vehicle is accelerated. The auxiliary switching control valve can work independently from opening/closing operations of the main switching control valve. Thus an enough quantity of intake air required for combustion in the diesel engine can be supplied, in addition, power performance of the combustion engine is ensured regardless of running conditions or heavy things loaded on a vehicle.

Abstract: A supercharged internal combustion engine includes an intake passage, a supercharger arranged in the intake passage, an exhaust passage, and a catalytic converter arranged in the exhaust passage. A supercharging pressure control system for the engine controls the opening of a supercharging pressure control valve for controlling supercharging pressure of intake air supplied to the engine by the supercharger. When the temperature of the catalytic converter falls outside a predetermined range, the opening of the control valve is controlled in a manner such that the temperature of the catalytic converter is brought into the predetermined range.

Abstract: A supercharged diesel engine is comprised an intake pipe, a diesel engine which is including an air cleaner and a cylinder which are installed both end of the intake pipe, respectively, a supercharger provided in the intake pipe and set to be driven by the diesel engine via clutch device, a bypass passage which is installed in the intake pipe in parallel with the supercharger, a bypass valve and a throttle device which are arranged on the bypass passage in series and the supercharger being supplied air in the case of that the bypass valve is opened and being rotated by the air.

Abstract: The combination of an intake air supply system with an internal combustion engine having a charge air cooler, a cylinder charging air intake and an exhaust discharge is provided. The intake air supply system includes a Roots-type positive displacement blower having inlet and outlet means and an exhaust gas driven turbo-compressor connected in series with the blower. The intake air supply system further includes a bypass passage connecting the blower inlet and outlet and a valve in the bypass passage to control the flow of fluid through the bypass. The valve is operative to open and close the bypass passage in response to engine operating parameters and to modulate the flow area of the passage in response to the same engine operating parameters so as to infinitely vary the flow area between the open and closed positions of the valve.

Abstract: An engine has a torque peak in a middle engine speed range. An engine output control system reduces the engine output torque in the middle engine speed range so that the torque characteristic curve of the engine becomes flat when the vehicle is accelerated from a low engine speed range at a low gear speed.

Abstract: A method for controlling the supercharge pressure in an internal combustion engine having a mechanical supercharger which is connected to the crankshaft in the engine and in which the internal compression ratio of the supercharger can be varied. In the method, the internal compression ratio of the mechanical supercharge is varied on the basis of at least a preset supercharge pressure and an engine revolution rate. This ensures that the supercharge pressure can be matched with the internal compression ratio to prevent a pulsing, thereby preventing noise from being generated.

Abstract: An intake system has an intake passage provided with a throttle valve and a supercharger for delivering a supercharger pressure to intake air engine cylinders. A bypass passage is connected to the intake passage so as to allow an intake air flow to bypass the supercharger. The intake air flow in the bypass passage is controlled by a valve, disposed in the bypass passage, which operates to variably cause the intake air to flow in the bypass passage only with a negative pressure created in the intake passage upstream of the supercharger. A pressure is applied to the valve during closing so as to cancel the supercharger pressure acting on the valve in an opening direction.

Abstract: A supercharged engine includes an intake passage, an engine located at one end of the intake passage, an air cleaner located at the other end of the intake passage, a mechanical supercharger located in the intake passage, a main throttle valve located at a downstream side of the intake passage, a sub throttle valve located at an upstream side of the intake passage so as to be larger than the main throttle valve in the opening ratio and linked with the main throttle valve. A relief passage, in parallel to the intake passage, is located between a downstream space between the mechanical supercharger and the main throttle valve and an upstream space between the mechanical supercharger and the sub throttle valve, and a relief valve located in the relief passage and responsive to a pressure-difference across the main throttle valve.

Abstract: The torque output of a fluidic torque converter that is driven by a supercharged engine and whose output is coupled to the input of a hydraulic automatic transmission is determined and compared with a transmission input torque limit which is a function of the transmission gear. The boost pressure output of the engine supercharger is limited based on this comparison to closed loop limit the torque output of the torque converter at the transmission input torque limit.

Abstract: A boost pressure control system for an engine, by which a boost pressure of the engine is controlled in accordance with a load of the engine. The system controls the boost pressure in two different control modes, i.e., an acceleration mode and a normal mode, and when a degree of acceleration required becomes larger than a predetermined value, the acceleration mode is selected in which the boost pressure is made higher than in the normal mode. To avoid a sudden drop of the boost pressure, the system maintains the acceleration mode even after the completion of the acceleration, until the engine load becomes low enough that the boost pressure drops to the level at which the switching to the normal mode does not cause a sudden pressure drop.

Abstract: A boost pressure control system for an engine, by which the degree of opening of the air bypass valve is adjusted and on/off of a mechanical supercharger operation is controlled to obtain an appropriate boost pressure. In the system, the degree of opening of the air bypass valve is adjusted in accordance with the load of the engine, based on different characteristics selected in accordance with whether the operation of the supercharger is started or stopped. If the engine is operated in a non-boost region, when the supercharger is operating the degree of opening of the air bypass valve is made larger to reduce the compression work of the supercharger, and when the operation of the supercharger is stopped, the degree of opening of the air bypass valve is made smaller to ensure that the air flow through the supercharger maintains the rotation of the rotors of the supercharger.

Abstract: In a supercharged pressure control valve apparatus of an internal combustion engine, a housing of supercharger has first and second by-pass air paths; a valve sheet formed on an end of the second by-pass air path; a rubber diaphragm having thick sealing part of convex and concave sectional shape at its outer periphery; a valve disc fixed to the moving part of the diaphragm and opening closing the first and the second by-pass air paths responding to movement of the diaphragm; and a casing of the valve directly fixed on the housing by sandwiching the outer periphery of the diaphragm.

Abstract: An air flow system includes a supercharger, a bypass passageway connected between an intake side and a discharge side of the supercharger, a compression machine and an air bypass valve in the bypass passageway. An intake port of the compression machine is connected with the bypass passageway such that supercharged air is delivered to the intake port of the compression machine at least during high supercharging conditions, thereby increasing the volumetric efficiency of the compressor at high engine speeds.

Abstract: An apparatus includes a compressor having a rotor portion, an inlet and a discharge. A motor portion of the apparatus has an intake manifold connected to the discharge. A throttle is displaceable between an open and a closed position for controlling fluid flow between the discharge and the intake manifold. A bypass return line connects the rotor portion of the compressor to the inlet. A piston valve, movable between an open location and a closed location, controls flow through the bypass return line. A control line, connecting the intake manifold to the piston valve, controls the location of the piston valve. A control valve may be included to control fluid flow through the control line. A computer, which is affected by the operation of the motor, controls the position of the control valve.

Abstract: An intake system comprises an intake passage provided, in order from an upstream side of the intake passage, with a throttle valve, a mechanical compressor supercharger and an inter-cooler for delivering supercharged air discharged by the supercharger into cylinders of an internal combustion engine. The intake passage has a supercharger bypass passage for allowing an intake air flow to bypass the supercharger, and an inter-cooler bypass passage for allowing a supercharged air flow to bypass the inter-cooler. Pneumatic valves, disposed, respectively, in the supercharger and inter-cooler bypasses passages, are controlled to open both the bypass passages when the internal combustion engine operates in a range of lower loads, to open at least the supercharger bypass passage when the internal combustion engine operates in a range of medium loads, and to close both the bypass passages when the internal combustion engine operates in a range of higher loads.

Abstract: A supercharging apparatus for an internal combustion engine includes a screw type supercharger having an inlet opening and an outlet opening. The supercharger is adapted to compress intake air for the engine in compression chambers between the openings when an electromagnetic clutch engages the supercharger with the crankshaft of the engine. The supercharging apparatus includes an intake air bypass passage for allowing the intake air to bypass the supercharger and a bypass control valve for closing the passage. The supercharger has a communication passage for allowing the two compression chambers to intercommunicate for relieving the compression chambers of the compression pressure therein. A controller allows the communication passage to relieve the compression pressure during the disengagement of the electromagnetic clutch and causes the bypass control valve to close the intake air bypass passage in association with the relief of the compression pressure by the communication passage.

Abstract: Supercharge pressure is vented from the induction manifold in response to a shift command for a shift which requires engine torque reduction for shift shock attenuation. The ignition is subsequently retarded during the inertia phase of the shift. The supercharge pressure reduces the amount of torque being produced by the engine prior a further reduction by ignition retardation. At the end of the inertia phase the ignition retard and pressure relief are stopped.

Abstract: In an internal combustion engine with a supercharger, a timing or timings for varying characteristics of kinetic supercharging effects of intake air are synchronized with a timing or timings for varying supercharging pressures by the supercharger. Reduction in engine torque at the time when the supercharging pressure is shifted, can be compensated for by enhancement in the engine torque generated at the time when the characteristics of the kinetic effect are varied.

Abstract: A mechanical supercharger of an internal combustion engine has a housing formed with inlet and outlet ports and a pair of spiral screws rotatably received in the housing for partially compressing air introduced in the mechanical supercharger and carrying it from the inlet port to the outlet port. The supercharger is disposed after a throttle valve in an intake system of the engine, and is provided with a relief port allowing compressed air to be relieved from the supercharger. The relief port is formed in the housing between the inlet and outlet ports where air is compressed to allow compressed air to be relieved. A relief valve is controlled to variably open according to engine operating conditions and relieve compressed air in the supercharger.

Abstract: A supercharging pressure control system for an automotive engine with a supercharger controlling a pressure of incoming supercharging air into the automotive engine. The pressure of the incoming supercharging air is feedback-controlled so as to reach a target pressure of supercharging air which is determined depending upon engine operating conditions. A feedback control gain is varied higher when the incoming supercharging air pressure is higher than the target supercharging air pressure when compared to being lower than the target supercharging air pressure.

Abstract: Control system for engine comprising supercharger for supercharging an intake gas introduced into the engine, pressure detector for detecting a supercharging pressure of the intake gas, supercharging pressure control device for controlling the supercharging pressure to a first predetermined pressure provided in accordance with engine operating condition, engine output control device for controlling an engine output other than the supercharging pressure control device. The engine output is restricted by the engine output control device when the pressure is increased beyond a second predetermined pressure which is greater than the first predetermined pressure. The second predetermined pressure is increased as the first predetermined pressure is increased for an improved supercharging pressure control.

Abstract: A system for controlling a boost pressure in an internal combustion engine is equipped with a turbocharger. Engine operation is divided into three regions based on an engine speed with respect to an engine load. Throughout the regions, a target boost pressure is predetermined to be considerably lower than a level at which knock frequently occurs. In the region where the engine speed and load are relatively high, the target boost pressure is gradually raised until knock occurs. When knock occurs, the target boost pressure is fixed at a value slightly lower than the value at which knock has occurred and thereafter the boost pressure is controlled to the fixed target pressure.

Abstract: A multi-cylinder internal combustion engine having a plurality of cylinders which do not fire one after another and intake ports for the cylinders. A mechanical supercharger is disposed in an intake passage. An intake resonance passage having no enlarged volume space or chambers, which consists of a resonance passage part and a collecting passage part directly communicating with the resonance passage part, is connected to an outlet port of an intercooler forming a pressure reflecting portion. The intake ports for the cylinders are separately communicated with the collecting passage part by way of a plurality of independent intake passages. A bypass passage is connected between the collecting passage part and the intake passage downstream the mechanical supercharger so as to form a circular passage running the mechanical supercharger, intercooler, intake resonance passage.

Abstract: In the present invention, in addition to a main throttle valve which is conventional, a sub-throttle valve for exclusive use of a mechanical supercharger is provided. By this sub-throttle valve, a flow rate of intake air is throttled by a fixed amount when the mechanical supercharger is switched from a non-connected state to a connected state. This makes it possible to prevent supercharged air from being bypassed to upstream of the supercharger through a bypass and also prevents generation of air intake noises. Moreover, in the case where the mechanical supercharger is of a type involving interior compression, at the time of the switching operation torque shock can be prevented and controllability of engine output by an accelerator pedal is improved.

Abstract: A slip value of a driving wheel is calculated on the basis of driving and driven wheel velocities detected by wheel velocity sensors. A target engine output of a vehicle is set in accordance with the slip value of the driving wheel. A target fuel amount to the engine is set in accordance with the target engine output. A target opening of a throttle valve is set based on the target fuel amount. An opening correction value of the throttle valve is calculated in accordance with a deviation between the target fuel amount and an actual fuel amount to the engine detected by a fuel controller. A traction controller controls to cause the engine output to coincide with the target engine output by ontrolling the opening of the throttle valve to attain an opening as a sum of the target opening and the opening correction value.

Abstract: An internal combustion engine has a mechanical super-charger in a conduit connecting the engine with a source of air for compressing the air in the conduit. A bypass passage connected to the conduit on opposite sides of the super-charger compressor is selectively closed by a pressure regulating valve having a valve member movable in response to a pressure differential on opposite sides of a diaphragm member. The diaphragm member is sensitive to a pressure change in the conduit occurring in response to movement of the throttle valve, and causes the valve member to open and reduce the load on the super-charger compressor when the throttle valve is closed.

Abstract: An engine is provided with a mechanical supercharger which is disposed in an intake passage of the engine and is driven by the output power of the engine. The supercharger is connected to and disconnected from the output power of the engine by a clutch. The engine has intake and exhaust valves which are opened and closed with an overlap time. A valve timing changing mechanism changes the overlap time in order to change the amount of air communicated between the intake and exhaust ports.

Abstract: A mechanical supercharger has a by-pass structure in the form of a valve body unitarily fixed to the supercharger housing at an end thereof opposite the drive gears for synchronously rotating the rotor shafts. The valve body contains a by-pass passage which is normally closed by a valve and which fluidically connects the outlet and the inlet of the compressor for permitting compressed gas to return to the inlet. The valve is slidably mounted on a shaft and is normally biased into the closed position by a spring, so that the valve will open the by-pass when the compressed gas pressure exceeds the spring force. The shaft itself is mounted to a diaphragm mechanism which can retract the shaft and open the valve in response to a pressure signal to the valve when supercharging is not necessary. Engine wear and fuel consumption are thus improved.

Abstract: Disclosed is an engine-control apparatus in which an exhaust passageway of the engine is provided with plural sound deadening passages. A portion of the plural sound deadening passages is designed to be opened or closed by a shift valve on the basis of a predetermined switching characteristic, and the pressure of the exhaust gases is changed upon the switching of the shift valve. In order to prevent torque shock to the driven wheels which may occur attendant upon operation of the shift valve to open or close or in order to reduce probability that torque shock would occur, there is provided a torque regulating apparatus which permits an adjustment of torque generator by the engine, of a transmission efficiency of power to the driven wheel, or of a switching speed at which the shift valve is switched to open or close, or a change in the switching characteristic.

Abstract: Supercharger device for reciprocating internal combustion engines, particularly for motor vehicles, comprising, inserted on the induction manifold of the engine, a rotary positive-displacement supercharger driven constantly by the motor shaft, the capacity and therefore the delivery pressure whereof is variable from a minimum value to a maximum value and vice versa by virtue of the corresponding controlled variation of the geometry of the pumping means constituted by a stator cylinder, a rotor and vanes.

Abstract: A supercharging pressure control device for an internal combustion engine provided with a supercharger includes a first intake passage interposed between the engine and the supercharger, a second intake passage interposed between a throttle valve and the supercharger, a by-pass passage interposed between first and second passages for by-passing the supercharger, a supercharging pressure control valve interposed between first and second passage for controlling the opening and closing of the by-pass passage and a control valve interposed between the first intake passage and the supercharging pressure control valve for increasing the value of the positive pressure in accordance with the increase of the RPM of the engine and the opening degree of the throttle valve.

Abstract: An air/fuel control system for a supercharged automotive engine includes a supercharger for supercharging air to be supplied to the engine, a detecting device for detecting a plurality of parameters representative of an engine operating condition, an air/fuel ratio regulating unit for adjusting the air/fuel mixing ratio to an arbitrarily chosen predetermined value, and a control unit for controlling the air/fuel ratio regulating unit. The control unit is designed to cause the air/fuel ratio regulating unit to adjust the air/fuel mixing ratio to a predetermined value higher than the stoichiometric value when the detecting device indicates that the engine is in a normal operating condition while the supercharger is operated, and also to adjust the air/fuel mixing ratio to a predetermined value lower than the stoichiometric value when the detecting device indicates that the engine is under an operating condition in which a relatively high engine power output is required.

Abstract: An intake air control system for an automotive engine having a turbocharger has a bypass provided around a compressor of the turbocharger and a control valve provided in the bypass. The control valve is connected to an accelerator pedal by a connecting mechanism. The connecting mechanism is so arranged that the control valve is opened in a low engine speed range and closed in a high engine speed range.

Abstract: The device allows the physical quantity used for the feedback-governing of the supercharging pressure of an internal combustion engine to be corrected as a function of ambient air temperature.