Abstract: In an automobile radar apparatus according to the present invention, a light-receiving optical system is rotated in response to an output from an image formation position calculation unit in such a manner that light source is focused on a vertical plane containing an optical axis of the light-receiving optical system; a direction up to the preceding vehicle is calculated from a turning angle in response to an output derived from an angular detecting unit; and a distance up to the preceding vehicle is calculated from an image position of the light source based upon an output derived from the image formation calculation unit.

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 (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: An air/fuel ratio detector includes an exhaust diffusion chamber having one wall formed by an oxygen pump and another wall formed by an oxygen-concentration difference-actuated electrochemical cell that generates an oxygen differential signal corresponding to the difference in oxygen concentration between exhaust gas in the diffusion chamber and the ambient atmosphere. The differential signal is compared to a reference signal and the difference is used to control a current supplied to the oxygen pump in order to control the oxygen concentration in the exhaust gas. The current level is an indication of the existing air/fuel ratio.

Abstract: A method to accurately sense the stoichiometric air-to-fuel (A/F) ratio by aintaining the electromotive force of an oxygen sensor at a predetermined value of about 100 mV and using an oxygen concentration measuring device of the solid electrolyte oxygen pumping type.

Abstract: This invention can accurately sense not only the stoichiometric air-to-fuel (A/F) ratio but also A/F other than the stoichiometric A/F by altering the electromotive force of an oxygen sensor at a predetermined value during the operation of an engine by using an oxygen concentration measuring device of the solid electrolyte oxygen pumping type.

Abstract: An air-to-fuel ratio detector for detecting the air-to-fuel ratio of the combustible mixture supplied to an engine on the basis of the concentration of oxygen gas in the exhaust gas of the engine, comprising an air-to-fuel ratio sensor provided to detect the oxygen gas concentration in the exhaust gas and consisting of an oxygen pump and an oxygen sensor which are disposed with a minute gap therebetween, and changeover means for simultaneously changing the direction of the pump current supplied to the oxygen pump and the polarity of the detection output signal given by the oxygen sensor; thereby capable of obtaining an air-to-fuel ratio detection signal when the operating air-to-fuel ratio is either in the rich air-to-fuel region or in the lean air-to-fuel region with respect to the stoichiometric air-to-fuel ratio.

Abstract: An air-to-fuel ratio sensor of a construction, wherein an oxygen concentration cell having a chamber, at least one side of which is communicative with the atmosphere and an oxygen pump are disposed in mutual confrontation through a clearance chamber, or a spatial chamber having a tiny hole for dispersion, and gas to be measured is introduced into this clearance chamber or the spatial chamber to measure its air-to-fuel ratio from an output of the oxygen concentration cell or a control quantity of the oxygen pump, thereby making it possible to control the internal combustion engine over a wide range other than its theoretical air-to-fuel ratio.