Abstract: In a traction control device in which an initial control torque of an engine is determined in accordance with an acceleration of the vehicle, when an excessive slipping of driven wheels is detected, a time taken for proceeding of the excessive slipping of the driven wheels from a large slip state to a small slip state is counted by a timer. If such time is smaller than a reference time and a gear ratio of the vehicle is of a first gear shift to provide a low vehicle speed, it is decided that the vehicle is traveling on an upward sloping road, and a lower limit value for defining the initial control torque of the engine determined in an initial control torque calculating means is corrected into an increased value in an initial torque correcting means. This prevents the initial control torque of the engine from being excessively reduced at the start of a traction control.

Abstract: An ignition system for an internal combustion engine capable of starting the engine even when a battery voltage is insufficient for ignition. A secondary voltage feedback circuit connected to a secondary winding of a transformer constituting a part of a DC--DC converter rectifies a secondary voltage of polarity opposite to that of the voltage applied to an ignition capacitor. The rectified voltage is fed back to the output side of the battery to compensate for lowering of voltage supplied to an ignition control circuit (10) from the battery (3).

Abstract: A disk apparatus having a readout circuit for providing readout data signals and capable of immediately detecting runaway of a readout clock signal generated from a VFO (Variable Frequency Oscillator) in the readout circuit if such occurs. The disk apparatus is free from a read error due to a permanent defect on a disk, e.g., an optical disk, or other causes. The disk apparatus includes a head for picking up signals from a disk, and a readout circuit for providing a readout signal and a readout clock signal, including a digitizing circuit for receiving and digitizing a data signal picked up by the head into a binary data signal, a reference clock generator for generating a reference clock signal and a variable frequency oscillator for receiving a read-gate signal, the digitized binary data signal and the reference clock signal and generating a readout data signal and a readout clock signal, each synchronized with the reference clock signal.

Abstract: A focus servo control system for use in optical disk drive units prevents a large current from continuously flowing through a focus actuator coil FC when a focus error signal FES in the focus servo loop increases while a track servo loop is in an "off" state, thereby preventing deterioration of the coil FC. The focus servo control further includes a controller for detecting a length of time during which an "off" state of the track servo loop in a servo controller continues, and for turning off the focus servo loop or, alternatively, reducing the gain of the focus servo loop when the detected length of time exceeds a predetermined value.

Abstract: A rectangular wave generator includes a comparator having a first input terminal receiving an input signal, a second input terminal, and an output terminal. The comparator slices the input signal at a hysteresis voltage so that a rectangular wave is output via the output terminal. The generator also includes a differentiating circuit connected between the output terminal and the second input terminal. The differentiating circuit functions as a feedback circuit. In lieu of the differentiating circuit, it is possible to use a feedback circuit connected between the output terminal and the second input terminal, the feedback circuit comprising a control unit for changing a feedback quantity of the differentiating circuit in accordance with variations in a frequency of the input signal.

Abstract: A traction control system for a four-wheel steerable vehicle includes a reference value generating circuit for generating a reference value for detecting a slippage of a drive wheel in a driving state, an output torque control device for controlling the torque of the drive wheel on the basis of an output from said reference value generating circuit so as to bring said drive wheel into a predetermined slipping state, and a reference value correcting circuit for correcting the reference value on the basis of a rear wheel steering angle. This makes it possible to insure a steering stability in a critical condition when a misalignment has been produced in phases of the front and rear wheels.

Abstract: An ignition control apparatus for an internal combustion engine in which the engine can not be started without the operation of a switch unit, thus preventing the theft of a motorcycle on which an ignition control apparatus of the invention is installed. A switch unit includes a key switch connected to a power source and a control element in the form of a resistor or a transistor. An ignition control unit is connected to the switch unit for supplying a key signal to the control element when the key switch is turned on, so that based on the key signal the control element energizes the ignition control unit for performing ignition control on the engine.

Abstract: A method for optical resolution of a DL-amino acid comprising reacting the DL-amino acid with an optically active N-acyl aspartic acid in a solvent or mixture of solvents, and separating the resulting two diasteromeric salts by way of the difference between their solubilities in the solvent or mixture of solvents. The difference in solubility may be enhanced by cooling, concentration, addition of a solubility-decreasing organic solvent, pH adjustment or salting out.