Abstract: To provide a data communication system in which a host computer is connected with a plurality of peripheral storage devices, which may carry out data transfer simultaneously without any substantial increase in data transfer time. A data transfer node includes a plurality of data compression means of different compression ratios, measuring means for measuring the effective data transfer rate of data transfer performed by the data transfer node over a communication channel, selection means for selecting one of the data compression means according to the effective data transfer rate obtained by the measuring means, and means for adding a data compression method to transferred data. A data receiving node includes means for decompressing received data by recognizing the compression method of the received data based on information about the compression method contained in the transferred data.

Abstract: A fuel control device for an internal combustion engine comprises an intake air flow sensor, a crank angle sensor, an intake pressure sensor, and means for calculating a predicted intake air quantity based on the engine rpm and the intake pressure. A failure of the air flow sensor is determined by comparing the predicted intake air quantity with the sensed intake air flow, and the fuel injection is controlled based on the output of the air flow sensor when it is normal and on the predicted intake air quantity when the air flow sensor has failed.

Abstract: An air-fuel ratio control apparatus for an internal combustion engine controls a fuel supplying means by a signal generated from an air-fuel sensor so that the air-fuel ratio of a gas mixture to be sucked into the internal combustion engine becoms a target air-fuel ratio. The air-fuel ratio control apparatus corrects the target air-fuel ratio by a parameter on the condition of the engine detected by the detecting means so that a fuel supplying device is controlled to obtain a corrected target air-fuel ratio.

Abstract: A fuel controller for an internal combustion engine has a misfiring sensor which can detect when misfiring occurs in an engine cylinder. When misfiring is detected, the fuel injector corresponding to the misfiring cylinder is prevented from supplying fuel to the misfiring cylinder, while the fuel injectors for the other cylinders continue to operate normally. The fuel injector for the misfiring cylinder can be disabled by a switching circuit which turns off a power amplifier for driving the fuel injector. Misfiring can be detected by sensing changes in the rotational speed of the engine between prescribed crankshaft angles due to a reduction in torque when misfiring occurs.

Abstract: In an air-fuel ratio control apparatus for an internal combustion engine, an air-fuel ratio sensor detects an air-fuel ratio in response to specified components contained in exhaust gas and an electronic control section receives a signal from the air-fuel ratio sensor to calculate an amount of fuel to be injected from a fuel supplying device so that the air-fuel ratio of a gas mixture to be supplied to the engine approaches a target air-fuel ratio. A parameter of a load for the engine and an engine revolution number are each detected, and the electronic control section calculates a correction coefficient on the basis of the parameter of the load and the engine revolution number, whereby the output of the air-fuel ratio sensor is corrected.

Abstract: A fuel controller for an internal combustion engine has a microprocessor which calculates the air intake rate per cylinder per suction stroke of the engine. The microprocessor detects misfiring when the air intake rate undergoes a large increase, due to a fall in enginie rotational speed caused by misfiring. The microprocessor prevents the fuel injector of a misfiring cylinder from supplying fuel to the misfiring cylinder.

Abstract: The air-fuel (A/F) ratio controller of an internal combustion engine related to the invention detects occurrence of abnormal condition in a heater on the basis of the resistance value of this heater which heats an oxygen sensor generating a specific voltage responsive to the difference of oxygen concentration between atmosphere and exhaust gas of the engine and of an oxygen pump allowing the pump current flow in order that the voltage can be the predetermined value. If abnormal condition arises in the heater, the A/F ratio controller stops fuel feedback control operation. The A/F ratio controller related to the invention forms a Wheatstone bridge circuit which includes the heater mentioned above and detects occurrence of an abnormal condition in the heater on the basis of the equilibrium condition of signal outputted from the Wheatstone bridge circuit.

Abstract: The invention relates to an air-fuel (A/F) ratio controller of an internal combustion engine, which is provided with a constant-voltage circuit between the heater for heating the A/F ratio sensor and the power-supply source. Regardless of variation of voltage outputted from the power-supply source, the A/F ratio controller securely maintains the heater voltage constant and prevents occurrence of error in the signal outputted from the A/F ratio sensor by correctly operating the oxygen-concentration detecting element whose measuring precision is solely dependent on temperature.

Abstract: An air-fuel control apparatus comprises an air-fuel ratio sensor comprising a gap portion for introducing exhaust gas generated from an engine, a solid electrolyte oxygen pump for controlling a partial pressure of oxygen in the gap portion and a solid electrolyte oxygen sensor producing an electromotive force in response to a proportion of the partial pressure of oxygen in the gap portion and a partial pressure of oxygen in other than the gap portion.

Abstract: An air-fuel ratio controller of an internal combustion engine stops current flow of an oxygen pump and power supply to an heater when the engine stops.In one embodiment the A/F ratio controller related to the invention stops power supply to the heater a predetermined period of time after the engine stops.

Abstract: An air-fuel (A/F) controller of an internal combustion engine, which computes an average value of a plurality of duty ratios of the voltage supplied to the heater according to the engine speed and the engine load periodically detected during a period from a predetermined moment up to the present, and fixes said average value as the present duty ratio of the voltage to be supplied to the heater, since the A/F ratio sensor is heated not only by the heater but also by exhaust gas. The A/F ratio controller smoothes the variation of voltage to be supplied to the heater by applying the computed average value as the present duty ratio of the supply voltage which is to be supplied to the heater. Accordingly, even when the driving condition is in high-speed, variation of the temperature borne by the heater is mild and smooth, and thus, the temperature of the oxygen-concentration detecting element does not rise suddenly.

Abstract: Techniques are provided for controlling the operation of an air-fuel ratio control apparatus for an internal combustion engine including feedback control of the air-fuel ratio control. The pump-driving voltage for flowing the pump-driving current used for changing the oxygen concentration is monitored and feedback control is suspended when the pump-driving voltage departs from a predetermined range.

Abstract: An air-fuel ratio control apparatus for an internal combustion engine comprises feedback control of the air-fuel ratio control, wherein a pump-driving voltage for flowing a pump-driving current is lowered to a predetermined value, and feedback control is suspended when the pump-driving current becomes lower than a predetermined value.