Abstract: A control system for a hybrid vehicle including an internal combustion engine, a drive shaft driven by the engine, a generator for converting kinetic energy of the drive shaft to electrical energy to generate electric power, and an electrical storage device for storing electrical energy output from the generator, wherein idling of the engine is detected. An amount of electrical energy to be regenerated by the generator during the idling of the engine is calculated. An output from the generator is calculated based on the amount of electrical energy to be regenerated by the generator. An amount of intake air supplied to the engine is controlled in a manner such that the amount of intake air to be supplied to the engine is increased when the generator regenerates electrical energy during the idling of the engine. And an air-fuel ratio of a mixture supplied to the engine is controlled to a leaner value than a stoichiometric value during the idling of the engine.

Abstract: A control system controls a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle, and electric energy storage unit for supplying electric energy to the electric motor.

Abstract: A control system is provided for a hybrid vehicle including an internal combustion engine, a drive shaft driven by the engine, a generator for converting kinetic energy of the drive shaft to electrical energy to generate electric power, and an electrical storage device for storing electrical energy output from the generator. Deceleration of the engine is detected. Supply of fuel to the engine is interrupted during the deceleration of the engine. An amount of intake air supplied to the engine is controlled such that the amount of intake air supplied to the engine is increased when the generator regenerates electrical energy during the deceleration of the engine. Calculation is made of an amount of electrical energy to be regenerated by the generator during the deceleration of the engine. An output from the generator is controlled based on the amount of electrical energy calculated.

Abstract: There is provided a control system for a hybrid vehicle including an internal combustion engine, a drive shaft driven by the engine, a motor operable on electrical energy for driving the drive shaft, and electrical storage device for supplying electrical energy to the motor. An amount of assistance of the motor to the engine by driving the drive shaft is calculated based at least on load on the engine. An output from the motor is controlled based on the amount of assistance of the motor to the engine. It is determined whether conditions are satisfied for a lean operating mode of the engine in which an air-fuel ratio of a mixture supplied to the engine is controlled to a leaner value than a stoichiometric value.

Abstract: A control system is provided in an internal combustion engine in which a valve timing such as an opening time point and lift amount of an intake valve can be switched to a low-speed or high-speed valve timing within a lean-burn control range established in accordance with the operational state, such as an intake pipe internal absolute pressure and an engine revolution number of the engine, wherein an air-fuel ratio of an air-fuel mixture supplied to the internal combustion engine is enriched for a predetermined time when the valve timing is switched from the low-speed valve timing to the high-speed valve timing while carrying out a lean-burn control.

Abstract: A process for the preparation of a readily hydrolyzable and/or biodegradable polyhydroxycarboxylic acid resin which can be used in agricultural materials, gardening materials, fishery materials, caking materials, medical instruments and materials, etc. and, even when discarded after use, which undergoes hydrolysis and/or is biodegraded into carbon dioxide, water, etc. Also disclosed are a hydrolyzable and/or biodegradable polyhydroxycarboxylic acid resin composition having an increased resin strength and melt viscosity, and a process for the preparation thereof.

Abstract: A system for controlling fuel injection in an internal combustion engine such that when the target air-fuel ratio is switched from a rich value to a lean value, the air-fuel ratios are switched to the lean value by sequentially decreasing the amount of fuel injected into the cylinders, for example in a four cylinder engine into the #1, #2, #3 and #4 cylinders, with predetermined time differences. During this time, an electronic air control valve (EACV) is controlled in such a manner that it is stepwise opened with the switching of the air-fuel ratios for the #1, #2, #3 and #4 cylinders, thereby causing the engine torque to remain the same to prevent the generation of a torque shock. When the target air-fuel ratio has been switched from the lean level to the rich level, the amounts of fuel injected into the #1, #2, #3 and #4 cylinders are controlled in such a manner that they are sequentially increased with predetermined time differences, and the EACV is controlled in such a manner that it is stepwise closed.

Abstract: A system for controlling fuel injection in an internal combustion engine such that when the target air-fuel ratio is switched from a rich value to a lean value, the air-fuel ratios are switched to the lean value by sequentially decreasing the amount of fuel injected into the cylinders, for example in a four cylinder engine into the #1, #2, #3 and #4 cylinders, with predetermined time differences. During this time, an electronic air control valve (EACV) is controlled in such a manner that it is stepwise opened with the switching of the air-fuel ratios for the #1, #2, #3 and #4 cylinders, thereby causing the engine torque to remain the same to prevent the generation of a torque shock. When the target air-fuel ratio has been switched from the lean level to the rich level, the amounts of fuel injected into the #1, #2, #3 and #4 cylinders are controlled in such a manner that they are sequentially increased with predetermined time differences, and the EACV is controlled in such a manner that it is stepwise closed.

Abstract: An air-fuel ratio control system for an internal combustion engine having a fuel injection valve for each cylinder and an electronic air control valve (EACV) for controlling intake air bypassing the engine throttle valve. When the target air-fuel ratio is switched over from a rich value to a lean value, the amounts of fuel injected into the cylinders, for example, #1, #2, #3 and #4 cylinders are controlled so that they are sequentially decreased at predetermined intervals, and the EACV is controlled to be opened stepwise. This causes a decrease in engine torque generated by the switching-over of the target air-fuel ratio to be offset by an increase in engine torque generated by an increase in amount of air drawn, thereby preventing the generation of a torque shock. At this time, the target opening degree of the EACV is corrected based on the magnitude of the interval and the magnitude of a loading of the internal combustion engine, thereby further effectively preventing the generation of the torque shock.

Abstract: There is provided a method for easily preparing a polyhydroxycarboxylic acid resin in a one pot reaction by adding 1,3-substituted-1,1,3,3-tetraorganodistanoxan as a polymerization catalyst to a hydroxycarboxylic acid, such as L-lactic acid containing 10 to 50% of water as a starting material, and stirring while heating under a reduced pressure condition or in an organic solvent.

Abstract: In an exhaust emission control system in an internal combustion engine which includes a spark plug disposed to face a combustion chamber, an intake system having a fuel injection valve disposed therein, an exhaust system having a catalytic converter incorporated therein and filled with a catalyst for reducing nitrogen oxide (NO.sub.x) in the presence of hydrocarbons in an oxidizing atmosphere, and an exhaust gas circulation amount control means capable of measuring and controlling the amount of exhaust gas circulated from the exhaust system to the intake system. The amount of exhaust gas circulated by the exhaust gas circulation amount control means the amount and timing of fuel injected by the fuel injection valve and the timing of ignition of the spark plug are controlled by a control unit, so that the amount of NO.sub.x discharged, is detected by the NO.sub.x detector in the exhaust system at a location downstream from the catalytic converter, is equal to or less than an acceptable amount of NO.sub.

Abstract: A commutator has such a construction that a flange having an outside diameter larger than the outside diameter of a cylindrical body is provided integrally with the cylindrical body in the vicinity of one end of the cylindrical body; guide grooves formed in a circular arc shape in cross section are provided on the flange at the boundary of the flange to the cylindrical body; engaging pieces passing through the guide grooves are provided on one end of a commutator segment; and engaging pieces are caused to deform plastically to fixedly fit the engaging pieces to the flange.

Abstract: An output correction method for a proportional-output type O.sub.2 sensor including an oxygen concentration detecting element formed by an oxygen-pumping element and a cell element, each of the oxygen-pumping element and the cell element being composed of a wall of a solid electrolytic material having oxygen ion-conductivity, and a pair of electrodes having the wall interposed therebetween. The oxgen-pumping element is supplied with an output voltage corresponding to a difference between a voltage developed between the electrodes of the cell element and a predetermined reference voltage, and current flowing in the oxygen-pumping element is detected. A correction resistance supplies information indicative of a deviation of an air-fuel ratio detected by the sensor with respect to a predetermined reference air-fuel ratio. A correction value is determined on the basis of the information and the direction of flow of the current. The detected current is corrected by the use of the determined corrected value.

Abstract: An air-fuel ratio control method for an internal combustion engine having an exhaust gas-ingredient concentration sensor provided in an exhaust system and generating an output proportional to the concentration of an ingredient in exhaust gases emitted from the engine. The air-fuel ratio of a mixture supplied to the engine is controlled to a desired air-fuel ratio corresponding to an operating condition in which the engine is operating, in a feedback manner responsive to the output of the sensor. Supply of fuel to the engine is interrupted while the engine is in a predetermined decelerating condition. The method comprises the steps of progressively decreasing the desired air-fuel ratio from a value larger than a value corresponding to the operating condition of the engine to the latter value after the engine leaves the predetermined decelerating condition, and controlling the air-fuel ratio of the mixture supplied to the engine to the progressively decreased air-fuel ratio in the feedback manner.

Abstract: A method of determining the deterioration of an oxygen concentration sensor for an internal combustion engine. The oxygen concentration sensor includes at least one oxygen concentration sensor element having an oxygen-pumping element and a cell element each composed of a member of a solid electrolytic material having oxygen ion-conductivity, and a pair of electrodes having the member interposed therebetween, and a current-detecting resistance serially connected to the oxygen-pumping element to form a series circuit. A voltage having a magnitude corresponding to a difference between a voltage produced between the electrodes of the cell element and a predetermined reference voltage is applied to the series circuit, and pumping current is detected from a voltage developed across the current-detecting resistance.

Abstract: An output correction method for an exhaust gas ingredient-concentration sensor for internal combustion engines. The sensor has two sensor elements having output characteristics different from each other. The sensor elements each produce an output proportional to the concentration of an ingredient in exhaust gases emitted from the engine. The sensor controls the air-fuel ratio of a mixture supplied to the engine to a desired air-fuel ratio by the use of an output from at least one of the sensor elements. First, it is determined whether or not the difference between the desired air-fuel ratio and an actual air-fuel ratio represented by the output of at least one of the sensor elements is smaller than a predetermined value. Then, an output value of one of the sensor elements is corrrected based on an output value of the other of the sensor elements when it is determined that the difference is smaller than the predetermined value.

Abstract: An oxygen concentration detecting device includes at least one oxygen concentration detecting element formed by an oxygen-pumping element and a cell element, composed of an oxygen ion-conductive wall, separating a pair of electrodes. The oxygen-pumping element and cell element define a gas diffusion chamber. A current detecting resistance forms a series circuit with the oxygen-pumping element. A voltage applying circuit applies to the series circuit an output voltage corresponding to the difference between a voltage between the electrodes of the cell element and a first reference voltage. An output detecting circuit outputs a voltage signal corresponding to a value of pumping current flowing through the resistance. An operational amplifier has a non-inverting input terminal supplied with a second reference voltage, an inverting input terminal connected to one end of the resistance, and an output terminal connected to the other end of the resistance.

Abstract: Leaf brushes for small electric motors having commutator slide surfaces for making electrical contact with a motor commutator and constructed so that a multiplicity of fine ridges are densely formed on the commutator slide surfaces.