Abstract: An anti-skid brake control system which employs a process of projection of vehicle speed representative dats based on selected higher one of data derived based on an integrated value which is derived by integrating vehicle body acceleration indicative data by time and data derived on the basis of wheel speed. In the present invention, vehicle speed representing data is periodically or cyclically reset and updated by the vehicle speed as an initial value of the vehicle speed representative data with that derived on the basis of the wheel speed. By selectively using the higher one of the vehicle speed representative data and periodically or cyclically updating the initial value of the vehicle speed representative data, a precision level of the vehicle speed representative level can be maintained high enough to precisely derive a wheel slippage for performing precise anti-skid control.

Abstract: A vehicle dynamic characteristic control apparatus for use with a motor vehicle having controllable dynamic characteristics. The apparatus comprises a first sensor sensitive to steering handle position for producing an electric signal indicative of a sensed steering handle position, and a second sensor sensitive to steering handle position for producing a steering handle neutral position signal having a first level when the sensed steering handle position is in a predetermined range and a second level when the sensed steering handle position is out of the predetermined range. A control unit is coupled to the first and second sensors. The control unit checks the steering handle neutral position signal. An estimation start command signal is produced when the steering handle neutral position signal is normal.

Abstract: A steering handle neutral position estimating apparatus for use with a motor vehicle having a steering handle operable to provide a driver's vehicle steering demand. The apparatus comprises a first sensor sensitive to steering handle position for producing an electric signal indicative of a sensed steering wheel position, and a second sensor sensitive to steering handle position for producing a steering handle neutral position signal having a first level when the sensed steering handle position is in a predetermined range and a second level when the sensed steering handle position is out of the predetermined range. The first and second sensors are coupled to an estimating unit which produces an estimation command signal when conditions determined for parameters that are sensed when the vehicle is operating are fulfilled. In the presence of the estimation command signal, a steering handle neutral position value is estimated when the steering handle neutral position signal is at its first level.

Abstract: A steering handle neutral position estimating apparatus for use with a motor vehicle having a steering handle operable to provide a driver's vehicle steering demand. The apparatus comprises a first sensor sensitive to steering handle position for producing an electric signal indicative of a sensed steering handle position, and a second sensor sensitive to steering handle position for producing a steering handle neutral position signal having a first level when the sensed steering handle position is in a predetermined range and a second level when the sensed steering handle is out of the predetermined range.

Abstract: An auxiliary steering control apparatus for use with a motor vehicle having a vehicle speed sensor sensitive to a vehicle speed. A control unit is coupled to the vehicle speed sensor for sampling the sensed vehicle speed at time intervals and calculating a vehicle speed change between a new value of the sensed vehicle speed and the last value of the sensed vehicle speed. The control unit calculates a control vehicle speed value which is equal to the new vehicle speed value when the calculated vehicle speed change is less than a limit value and is equal to the last vehicle speed value plus the limit value when the calculated vehicle speed change exceeds the limit value.

Abstract: An anti-skid brake control system is associated with a control system for a power train which controls power train operation mode between a four-wheel drive mode, in which all four wheels are coupled with an automotive internal combustion engine to be distributed torque according to a controlled distribution ratio of an engine driving torque, and a two-wheel drive mode, in which two auxiliary driving wheels are disconnected from the engine to be free from engine driving torque and two driving wheels are connected to the engine to receive the engine driving torque. The anti-skid brake control system is so associated with the power train control system as to normally set the power train operation mode into the two-wheel drive mode during active state of anti-skid brake control, and to set the power train operation mode into the four-wheel driven mode in response to wheel slippage at the primary driving wheels greater than a predetermined threshold value.

Abstract: An anti-skid brake control system is associated with a mechanism which controls an engine revolution speed. The anti-skid brake control system includes means for monitoring a period of time in which anti-skid control is maintained in a RELEASE mode to decrease braking pressure. The monitoring means is responsive to the period of time exceeding a predetermined period for driving the engine speed control mechanism to temporarily accelerate the engine to assist recovery of the wheel speed.

Abstract: An anti-skid brake control system comprises a limiter which provides an upper limit of variation of wheel speed indicative data. The limited wheel speed indicative data is derived with respect to each wheel. The greatest limited wheel speed indicative data is selected as vehicle body speed indicative initial data. The anti-skid brake control system derives a projected vehicle body speed indicative data by adding an integrated value of a longitudinal acceleration to the aforementioned vehicle body speed indicative initial data. The integrated value is provided with a predetermined offset value for compensating for error caused in a longitudinal acceleration sensor.

Abstract: An anti-skid brake control system two mutually different mode for projecting the vehicle body speed representative data. In the first mode, the vehicle body speed representative data is derived on the basis of an instantaneous wheel speed data which is latched upon initiation of vehicular braking operation or upon detection of vehicular braking deceleration, and an integrated value of a longitudinal acceleration indicative signal. On the other hand, in a second mode, the vehicle body speed representative data is derived on the basis of the initially latched instantaneous wheel speed data and a fixed value of wheel deceleration gradient data. A first vehicle body speed representative data derived through the first mode of operation and a second vehicle body speed representative data derived through the second mode of operation are selectively used as the vehicle body speed representative data.

Abstract: An anti-skid brake control system includes a device for detecting the friction level of a road surface. The system performs mutually different modes of arithmetic operation for deriving wheel acceleration data on the basis of wheel speed monitoring data. Respective modes of arithmetic operations are provided different levels of response characteristics and noise elimination levels adapted for road friction levels. The system selects one of the arithmetic operation modes for deriving the wheel acceleration data depending upon the friction level on the road surface.

Abstract: An antiskid brake control system of a vehicle includes a detecting section for sensing or estimating various parameters such as vehicle speed, wheel speed, wheel slip rate, first time derivatives of the vehicle speed and wheel speed, and second time derivative of the vehicle speed and wheel speed, a control section for determining a manipulated quantity by a fuzzy inference based on the values of the parameters, and a modulator section for varying a brake fluid pressure in accordance with the manipulated quantity.

Abstract: A relay valve is operatively disposed between a pressurized air source and a work chamber of a brake booster. The relay valve has a pilot chamber so that the relay valve can feed the work chamber with a pressurized air, the pressure of which corresponding to that of a pressure applied to the pilot chamber. Electromagnetic valves are arranged to selectively connect the pilot chamber with the pressurized air source and the atmosphere. The valves are so controlled by an electronic control unit that the pilot chamber is supplied with pressurized air the pressure of which being determined in accordance with a brake pedal force applied from a brake pedal to an input means of the booster.

Abstract: An ignition system for an internal combustion engine comprises a voltage boosting means which generates a high DC voltage by boosting a low DC voltage, a capacitor which charges the high DC voltage from the voltage boosting means, and ignition coil means having a secondary winding to which the high DC voltage is applied from the boosting means, wherein a high capacitive energy charged within the capacitor is supplied into one of spark plugs located within a corresponding engine cylinder in which a spark discharge has started and subsequently the output energy from the boosting means is supplied into that spark plug via the secondary winding of the ignition coil. Consequently, the ignition energy can sufficiently be supplied immediately after an ignition start to which a combustion characteristic is closely related and the complete combustion of air-fuel mixture can be achieved over the whole range of engine revolutional speed.

Abstract: There is provided an engine ignition device which generates a high voltage in the secondary windings of the ignition coil through switching on and off of the electric current flowing in the primary windings by means of an ignition circuit. The generated high voltage is impressed on the ignition plugs to initiate ignition, and, at the same time, the high voltage is boosted by a DC-DC converter connected to the secondary windings and is supplied continuously to the ignition plugs, to prolong the discharge duration. There is further provided a DC-DC converter controlling circuit to control the DC-DC converter to initiate ignition synchronous with the ignition signal output and also to reduce the operating time of the DC-DC converter as the engine increases its speed.

Abstract: An N cylinder internal combustion engine plasma ignition system comprises a DC-DC converter for boosting low DC voltage to high DC voltage. Each of N ignition energy charging circuits includes a first capacitor connected between the DC-DC converter and ground via first and second diodes. The capacitor is charged by the DC-DC converter. Each of N reverse blocked thyristors connected to a junction of the first diode and first capacitor selectively grounds an electrode of the corresponding first capacitor to discharge ignition energy stored in the first capacitor. For each cylinder a transformer connected between the first capacitor and a spark plug boosts and feeds the discharged energy to the plug. One end of the transformer primary winding is grounded via a second capacitor to generate a damped oscillation when the corresponding thyristor grounds the first capacitor.

Abstract: A diesel engine is started by plural ignition plugs, each installed in a swirl chamber of a corresponding cylinder. Each ignition plug includes (a) an elongated center electrode, (b) a fuel-absorbent electrical insulator that encapsulates the center electrode so as to allow only one end of the center electrode to protrude, and (c) a plurality of elongated grounding electrodes arranged symmetrically around said insulating member to define a discharge path in conjunction with the protruding end of the center electrode. The discharge path includes part of the surface of the insulating member and an air gap between free ends of the grounding electrodes and opposing surfaces of the insulating member.

Abstract: A plasma ignition system for an internal combustion engine which varies a discharge time of a plasma ignition energy charged capacitor according to the engine operating condition, e.g., the current engine speed.

Abstract: A plasma ignition system for an engine having any number of engine cylinders, which comprises: (A) a plurality of plasma ignition plugs each mounted within a corresponding engine cylinder; (B) a first power supply unit for supplying a first electric power into each plasma ignition plug so as to generate a spark discharge within each plasma ignition plug; (C) a first switching circuit for sequentially connecting the first power supply unit to each plasma ignition plug according to a predetermined ignition order; (D) a second power supply unit for supplying a second electric power into each plasma ignition plug so as to generate a high-temperature plasma gas within each plasma ignition plug; and (E) a second switching circuit for sequentially connecting two of the plasma ignition plugs within the respective engine cylinders, one engine cylinder being at the start of an explosion stroke and the other engine cylinder being at almost end of an exhaust stroke, in a predetermined delay after the occurrence of the sp

Abstract: In an auxiliary ignition system for starting a diesel engine having a plurality of plasma spark plugs installed in corresponding combustion chambers facing fuel injection valves, starting time is reduced by applying high ignition energy to the plugs following predetermined time intervals after fuel injection to the corresponding engine cylinders.

Abstract: An ignition system for a multi-cylinder internal combustion engine having a spark plug within each engine cylinder, wherein a single DC-DC converter is provided and a high-voltage withstanding characteristic capacitor is provided for each spark plug. The capacitor charges to the high DC output voltage of the DC-DC converter and operatively supplies the high DC voltage via a boosting transformer into the corresponding spark plug at a predetermined ignition timing. The amount of the discharge energy being varied according to the pulse width of an input signal of each switching circuit which operates to supply the charged high DC voltage of the capacitor into the corresponding spark plug, the pulse width being varied according to various engine operating conditions.