Abstract: A refrigeration cycle or an air conditioner including a refrigeration cycle is subjected to feedback control based on modern control theory. An apparatus controlling a controlled object, that is, the refrigeration cycle of the air conditioner including the refrigeration cycle, is formed as an optimal regulator. A controlled input to the controlled object includes a capacity of a compressor or a degree of opening of an expansion valve. A control output from the controlled object includes a temperature of air at a point downstream of the evaporator or a superheat of refrigerant. Feedback gains are predetermined by use of dynamic models constructed for respective steady operation states of the controlled object.

Abstract: Disclosed a brake control system for stably performing the brake control of a motor vehicle. The brake control system is arranged so as to control a braking pressure applied to a vehicle wheel so that the wheel speed becomes equal to a target wheel speed. The target wheel speed is determined on the basis of a predetermined slip ratio of the wheel and the vehicle speed of the wheel portion. The vehicle speed of the wheel portion is derived as a function of the turning radius determined in the steering amount of the vehicle and the vehicle speed. The brake control system is preferably constructed as an integral-added optimal regulator which controls the braking pressure on the basis of an optimal feedback gain predetermined in accordance with a dynamic model of a system performing the brake of the vehicle.

Abstract: Disclosed is a vehicle speed control system for controlling the intake air amount introduced into an engine of a vehicle in order to allow the vehicle to travel at a target speed. The intake air amount is controlled in accordance with the integration value of deviation of the vehicle speed from the target speed. The integration value is rest when the vehicle acceleration is terminated and the reset integration value is derived on the basis of the vehicle speed and throttle valve opening degree. The vehicle speed control system includes an integral-added optimal regulator which determines the feedback amount on the basis of an optimal feedback gain predetermined in accordance with a dynamic model of the system relating to the constant travelling speed of the vehicle.

Abstract: An anti-skid control system for a vehicle with at least one wheel. The anti-skid control system includes a wheel sensor for sensing a rotational speed of the wheel and for generating a signal indicative of the sensed wheel speed and a brake sensor for sensing a braking force of a braking device which brakes the wheel and for generating a signal indicative of the sensed braking force. The wheel sensor and the brake sensor are respectively coupled to a control unit for receiving the wheel speed signal and the braking force signal to control the braking force of the braking device to a target braking force so that a slip ratio of the wheel assumes a predetermined value. The control unit determines the target braking force at the time of start of the anti-skid control to be equal to a braking force corresponding to the resultant of torques developed in the wheel at the control start time.

Abstract: Disclosed is a brake control system for a motor vehicle comprising a wheel braking device (M5) for providing the braking of a wheel of the vehicle in accordance with pressure, a braking pressure adjusting device (M6) for adjusting the braking pressure applied to the wheel braking device (M5), a detector (M4) for detecting a rotational state of the wheel, a rotational state setting device (M8) for setting an optimally rotational state of the wheel in according with an operating condition of the vehicle, and a control unit (M9) for feedback-controlling the braking pressure adjusting device (M6) so that the detected rotational state is equal to the set rotational state.The control unit (M9) is constructed as an integral-added optimal regulator which controls the braking pressure adjusting device (M6) on the basis of an optimal feedback gain predetermined in accordance with a dynamic model of a system relating to the brake of the vehicle.

Abstract: The required rate of acceleration of a vehicle is detected. The speed of the vehicle is detected. The rotational speed of a vehicle driving wheel is detected. An air adjusting device adjusts the rate of air flow into a vehicle powering engine in accordance with an adjustable controlled quantity. A target rotational speed is determined on the basis of the detected required acceleration rate. The controlled quantity of the air adjusting device is feedback-controlled so that the detected rotational speed of the driving wheel essentially equals the target rotational speed. The output torque of the engine is estimated in accordance with the detected rotational speed of the driving wheel and the controlled quantity of the air adjusting device.

Abstract: Disclosed is an air conditioner for automobiles comprising an air conditioning unit for adjusting at least temperature of blow-off air discharged into a vehicle compartment, a decision device for determining whether the air conditioning unit is in an initial state that the air conditioning unit is started, and an air conditioning control unit for feedback controlling the air conditioning unit so that the detected internal temperature becomes equal to the set target temperature. The air conditioning control unit is formed as an integral-added optimal regulator which performs the feedback control on the basis of optimal feedback gain predetermined in accordance with a dynamic model of an air conditioning system. The air conditioning control unit outputs to the air conditioning unit controlled variables decided in accordance with the results of the determination made by the decision device.

Abstract: In an air conditioner for automobiles, control unit for performing feedback control of blow off air is constructed in the form of an integral-added optimal regulator (M4) which performs the feedback control on the basis of optimal feedback gain predetermined according to dynamic model(s) of an air conditioning system including the vehicle compartment (M1) and the used air conditioning unit (M2). According to another feature of the present invention, an environmental condition, such as solar radiation to the vehicle compartment (M1), is detected to further accurately control the internal air temperature. In one embodiment, the internal variables including optimal feedback gain of the integral-added optimal regulator (M4) are changed in accordance with the variation in the dynamic model depending on the detected environmental condition.

Abstract: The vehicle height control apparatus according to the present invention comprises, vehicle height detecting unit (M3) provided at an appropriate position of a vehicle (M1) for detecting the distance between a body (M2) of the vehicle (M1) and the surface of road; vehicle height adjusting members (M5) provided between the body (M2) of the vehicle (M1) and wheels (M4) of the vehicle (M1) for adjusting the height of the a vehicle (M1); vehicle height control unit (M6) for obtaining controlled variable of the vehicle height adjusting members (M5) so that the actual vehicle height detected by the vehicle height detecting unit (M3) equals the predetermined target height and for driving the vehicle height adjusting members (M5), the vehicle height control unit (M6) being formed as an integral-added optimal regulator which determines the controlled variable of the vehicle height adjusting members (M5) on the basis of an optimal feedback gain predetermined in accordance with dynamic model of the system relating to the

Abstract: A case for accommodating an electronic circuit for an electronic control system mounted on a vehicle is formed of an electric conductor and is electrically isolated from the grounding terminal of the electronic circuit which is provided on a printed substrate. Further, the outer boundary of a signal line for signal transmission between the electronic circuit and external circuits or sensors of the case is connected to the case through capacitors, thus preventing the faulty actuation of the electronic control system which otherwise might be caused by the electromagnetic wave.

Abstract: Apparatus for controlling the operating state of an internal combustion engine (M1), has a demand amount detecting an unit (M2) for detecting amount of demand to the engine, an operating condition varying unit (M3) for varying a condition of operation of the engine, an operating state detecting an unit (M4) for detecting operating state of the engine, a target value setting unit (M5) for determining target values of variables of the operating condition, a control unit (M6) for controlling the operating condition varying unit (M3) by determining feedback amount of the operating condition variables so that detected values equal to the target values.

Abstract: A control apparatus for diesel engines controls the energization of glow plugs each of which is disposed in a cylinder of a diesel engine and heated by an energizing current flowing therethrough. When fuel supply to the engine is resumed after the engine temperature has fallen due to the interruption of fuel supply during a decelerating operation of the engine and further when fuel supply is enriched during an accelerating operation of the engine while it is cold, the control apparatus controls the energization of the glow plugs, thereby promoting the combustion of the engine and improving the combustion efficiency of the engine.

Abstract: An engine crank angle determining arrangement including a rotor having teeth or slits wherein either a tooth is entirely omitted or the teeth or slits are formed with non-uniform intervals therebetween. The teeth or slits are detected by an electromagnetic pick-up device or a photocoupler, and the time intervals corresponding to the intervals between the teeth or slits in the signal thus detected are processed in accordance with a predetermined program. The time intervals thus processed are corrected in consideration of an engine low state or non-low state operating condition, such as for example transient condition or starting condition, of the engine. Processing is carried out in either of two different ways of calculating reference angles.

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: In an electronic ignition control apparatus having RAM to initially store first and second signals indicative of the starting and terminating points for calculation of a time necessary for rotation of a predetermined angle defined by integer times as large as a predetermined angular interval of an output shaft of an engine, a rotation time of the output shaft is calculated during rotation of an angle of the output shaft defined by the first and second signals from RAM to calculate an optimum spark advance angle in relation to the operating condition of the engine such that an angular position defined by integer times as large as the predetermined angular interval at the advance angle side of the calculated advance angle is determined to be stored in RAM as a third signal.

Abstract: An injector drive circuit in which the injector is opened in response to a pulse signal with a time width which determines the quantity of the fuel to be supplied to the engine. To the injector, a circuit for supplying a peak current at the time of fuel injection and a field effect transistor for supplying a holding current after supply of the peak current are connected in parallel. In response to the control signal from a fuel injection amount control circuit, the peak current is supplied to the injector, and upon detection that a predetermined peak current has been supplied to the injector, the peak current is stopped. Thereafter, by controlling the gate of the field effect transistor, the holding current is supplied to the injector through the field effect transistor, until the control signal is stopped.

Abstract: In an electronic ignition control apparatus having RAM to initially store first and second signals indicative of the starting and terminating points for calculation of a time necessary for rotation of a predetermined angle defined by integer times as large as a predetermined angular interval of an output shaft of an engine, a rotation time of the output shaft is calculated during rotation of an angle of the output shaft defined by the first and second signals from RAM to calculate an optimum spark advance angle in relation to the operating condition of the engine such that an angular position defined by integer times as large as the predetermined angular interval at the advance angle side of the calculated advance angle is determined to be stored in RAM as a third signal.

Abstract: An injector drive circuit for driving an injector having a valve opened and closed according to a pulse signal with the pulse duration thereof corresponding to the quantity of fuel supplied to the engine. The injector drive circuit comprises a current supply power transistor connected to an injector coil. According to an electric pulse signal from a fuel injection control circuit, a first current control section causes base current to flow into the power transistor for causing a peak current through the injector coil. When a predetermined peak current is detected, the base current supplied by the first current control section is cut off. From this instant till the disappearence of the electric pulse signal, a second current control section, which supplies base current to the power transistor only when the current supplied from the power transistor to the injector coil becomes lower than a working current level, supplies in effect the working current through the power transistor to the injector.

Abstract: A record disc cutting stylus comprises a cutting stylus body which is held at its upper end by a shank. At its lower end, there is a stylus tip portion which has a mirror surface, a relief surface with a relief angle .gamma., and a burnishing facet with a burnishing angle .beta. and a burnishing facet width d. The burnishing angle .beta. is as large as possible, and the width d and the relief angle .gamma. are as small as possible. The stylus projects distance l between the lower end face of the shank and the extreme tip of the stylus tip portion, which projection is as small as possible. The burnishing angle .beta. has a value substantially within a range of 25.degree. to 40.degree.; the burnishing facet width d is substantially within a range of 0.5 .mu.m to 3.0 .mu.m; the relief angle .gamma. is substantially within a range of 30.degree. to 40.degree.; and the stylus projecting distance l is substantially less than 2.0 .mu.m.

Abstract: A multichannel record disc recording system comprises circuits for forming first and second sum signals and first and second difference signals respectively from signals of two different channels of four channels. The first and second difference signals, are angle modulated and, a control signal is formed in accordance with the level of at least one of the first and second sum signals and the level of at least one of the first and second difference signals. The levels of the first and second angle-modulated signals are controlled in accordance with the control signals thus formed. Circuits are provided for multiplexing the first sum signal and the first angle-modulated difference signal thus level controlled, and for multiplexing the second sum signal and the second angle-modulated difference signal thus level controlled. These multiplexed signals are then recorded on a record disc.