Abstract: An engine mount which is capable of changing its vibration transmission characteristics with a simple structure using an inexpensive actuator is provided. A partition is inserted to a side member to which a mount rubber (rubber vibration isolator) of the engine mount is spliced to close a space between the mount rubber and to create an air chamber. An air duct pipe which communicates with the air chamber is connected to the side member and is connected to a VSV (vacuum switching valve) via a connection pipe. The VSV is controlled to ON/OFF states based on a driving voltage Vout from an ECU which corresponds to explosive vibrations of the engine to switch pressure within the air chamber to negative pressure of a vacuum tank in which negative pressure of an intake manifold is accumulated or to atmospheric pressure, interlocking with the vibration of the engine.

Abstract: A vibration isolator designed to improve mounting facility is disposed between a vibration source and a base on which the vibration source is supported. The vibration isolator has an elastic member provided between the vibration source and the base to elastically support the vibration source, a main chamber in which a fluid is enclosed and the volume of which is changed according to a deformation of the elastic member, a sub chamber defined by an elastic membrane and communicating with the main chamber through an orifice, a moving member provided in a fluid chamber formed by the main and sub chambers, and an actuator for driving the moving member. The actuator is fixed to the elastic membrane in a fluid sealing manner, and drives the moving member from the outside of the fluid chamber formed by the main and sub chambers through attachment members connected to the moving member.

Abstract: In engine control apparatus with exhaust gas recirculation control and air/fuel ratio feedback control, the amount of recirculated exhausted gasses is accurately detected so as to operate an internal combustion engine under an optimal operating condition all the time. To this end a correction factor derived from oxygen sensor output, which is used for air/fuel ratio control, is monitored to obtain a difference of a correction factor value resulted from engine operation with EGR and another correction factor value resulted from engine operation with EGR. This difference is obtained by forcibly interrupting EGR operation. Once the amount of recirculated exhaust is accurately estimated, the EGR control and/or air/fuel ratio control are performed with compensation for possible error due to secular change in EGR system.

Abstract: An air flow measuring apparatus having a measuring plate provided within an air intake pipe and a potentiometer having divided resistor material, a slider support member and switching contacts in which the shaft of the measuring plate and the shaft of the slider support member of the potentiometer interlock with each other, and corresponding electrical signals are produced from the potentiometer in accordance with the pivotal movement of the measuring plate, which pivotal movement is proportional to the intake air flow. With this construction, highly accurate measurement of the intake air flow is possible even with low manufacturing cost for the apparatus.

Abstract: Engine operating parameters are detected to see whether the engine is in idle state or not. Then the speed of the engine is detected to determine whether engine speed is varying or not. To this end, a plurality of engine speed data are averaged to find an average engine speed which will be used as a reference value for the comparison with respect to a latest instantaneous engine speed. Ignition timing is either retarded or advanced for maintaining the engine speed at a desired value in such a manner that the amount of correction of the ignition timing is determined by deriving data from a memory in which relationship between the engine speed variation and ignition timing correction amount is stored in the form of a map. In the case that the average engine speed is far deviated from a setting engine speed, the average value is not used as the reference value, but rather the setting speed is used to find the difference.

Abstract: In an internal combustion engine, a basic fuel injection pulse width is calculated by parameters such as the engine speed and the intake-air quantity. The basic pulse width is compensated for by an integration compensation factor and a learning correction factor so as to obtain a desired air-fuel ratio. A predetermined number of integration compensation factors are sampled at every air-fuel ratio transition, and the mean value thereof is calculated. The learning compensation factor is corrected in accordance with the mean value of the predetermined number of integration compensation factors.

Abstract: The idle speed of an internal combustion engine is controlled in response to a variable ignition timing control signal from a microcomputer. The microcomputer derives this control signal as a function of the magnitude of engine speed variation which occurs during engine idle periods to cause the ignition timing to vary quickly in response to a transitory engine load variation. An auxiliary air delivery system may be advantageously incorporated in the idle speed control system to cooperate with the ignition timing control in response to the engine speed variation.

Abstract: In a method for controlling the fuel injection in an internal combustion engine by using an electronic control device for triggering the fuel increase in the engine acceleration state, the fuel increase is prohibited or modified during gear change operations of the automobile driven by the engine corresponding to the detection of the state where the rate of change of the ratio between the intake air amount is algebraically less than a predetermined value, or to the output signal of a clutch switch.

Abstract: In a closed loop idle engine speed control system the actual engine speed is compared with a reference idle speed during engine warm-up periods to control the amount of an air flow introduced to the engine through an auxiliary air delivery system so that the difference between the actual and reference engine speeds is reduced. The reference setting of the idle speed is varied as a function of the engine temperature in order to vary the actual engine speed in response to an increase in the engine temperature. The auxiliary air delivery system includes a linear solenoid type electromagnetic valve which comprises a spring-biased valve member normally maintained in a neutral position with respect to the valve seat to allow introduction of a predetermined amount of auxiliary air to the engine and a pair of coils energized respectively with a current representing the difference in engine speed to move the valve member in opposite directions to increase or decrease the auxiliary air supply.

Abstract: A method and apparatus for controlling the rotation speed of an engine by the steps of calculating a desired value of the idling rotation speed of the engine, sensing the actual idling rotation speed of the engine, calculating the deviation of the sensed actual idling rotation speed from the desired value, calculating a data of a rotation speed control factor on the basis of the deviation, limiting the control factor to within a control range between an upper limit and a lower limit, storing a correction factor related to a value of the control factor used under a specific operating condition of the engine, calculating the upper limit and the lower limit of the control factor using the value of the correction factor, and controlling the amount of intake air or the amount of the air-fuel mixture supplied to the engine on the basis of the value of the control factor thus calculated.

Abstract: To control the idling speed of an automotive engine, a control amount is predetermined which determines an idle air flow for providing a basic idling speed and the idle air flow is adjusted in accordance with the control amount. Also, when the engine is idling after the completion of the warm-up operation, in accordance with the difference between a predetermined desired engine idling speed and the actual engine speed attained after the adjustment of the idle air flow in accordance with a basic control amount, a correction value for compensating the basic control amount is computed and memorized such that the actual engine idling speed is adjusted to the desired speed, whereby the idle air flow is adjusted in accordance with the memorized correction value and the basic control amount in all the engine operating conditions including the idling operation.

Abstract: A method for controlling the supply of fuel and ignition spark for an internal combustion engine. The supply of fuel which is mixed with air is cut off upon engine deceleration and resumed thereafter. At the transition from the cut-off to resumption of supply of fuel, the timing of ignition spark which ignites the mixture of air and fuel is retarded enough to prevent an abrupt increase in an engine output torque. The retarded timing of ignition spark is then advanced gradually as the time passes so that the engine output torque increases gradually.

Abstract: A combustion system for internal combustion engines having an exhaust gas recirculating system which is operable by a lean air-fuel mixture without aggravation of the combustion. The piston of the engine has a sub-piston projecting on the top thereof and the cylinder head is formed with a recess into which the sub-piston is insertable at a position near the top dead center of the stroke of the piston such that the space between the cylinder head and the piston can be divided into two combustion chambers. The compression ratios of both chambers are different from each other. An ignition plug is disposed in the chamber having the lower compression ratio, and ignition of the air-fuel mixture in the chamber having the higher compression ratio takes place by flame from the lower compression ratio chamber as a torch ignition.

Abstract: An engine control system which controls the engine fuel injection amount and the ignition timing by being supplied with and processing the rotational speed signal produced on the basis of the output of a rotational speed sensor producing the rotational speed signal at every predetermined engine crank shaft angle and an intake air amount signal from an air amount sensor for detecting the intake air amount of the engine. At certain predetermined engine rotational angles, the rotational speed signal and the intake air amount signal are read and compared with the previously-read rotational speed signal and intake air amount signal respectively, thus detecting changes therein respectively. These changes and signal values are used to correct control signals for ignition timing and fuel injection amount.

Abstract: A heat insulation construction for gasoline engines comprising a piston, a sub-piston projecting on the top of the piston. A cylinder head is secured to the top of a cylinder and has a recess into which the sub-piston may be inserted at a position near the top dead center of the piston stroke to form two independent combustion chambers. An ignition plug is provided in one of the combustion chambers in the cylinder head. An intake passage and exhaust passage are provided in the cylinder head. A heat insulating air layer is provided in the top portion of the piston and sub-piston, and a heat insulating air layer is provided on the inner wall of the cylinder head, which is formed by casting hollow structures made of steel plates in the cylinder head.