Abstract: A fuel tank stores fuel gas. A catalytic burning section is connected to the fuel tank for generating heat based on an oxidative reaction between the fuel supplied from the fuel tank and air. The fuel tank and the catalytic burning section are assembled as a catalytic heat generating apparatus. The catalytic heat generating apparatus is detachably installed in a housing of a heater section. The heater section has both ends provided with a pair of belt portions wound around a user's body.

Abstract: A method of detecting an abnormality in a crank angle signal of an internal combustion engine having a crankshaft.

Abstract: An ignition timing control system for an internal combustion engine comprises magnetic pick-up means for magnetically sensing the angular position of the crankshaft and for generating an output signal indicative thereof, control means for controlling the ignition timing of the engine based on the output signal from the magnetic pick-up means, and correction means for correcting the ignition timing to be controlled by the control means for a delay in the generation of the output signal, which delay increases with a rise in the rotational speed of the engine.

Abstract: An ignition timing control method for an internal combustion engine in which an ignition advance angle value conforming to the operating condition of the engine is set, an ignition timing is obtained by applying an angle-time conversion to a crank angle extending from a reference crank angle position to a position corresponding to the ignition advance angle value, and ignition is effected upon lapse of the ignition timing from an instant at which the reference crank angle position is sensed. Engine rotational speed value is sensed at least at two particular crank angle positions, and each sensed rotational speed is stored in memory. A ratio between the at least two rotational speed values stored in an immediately preceding ignition cycle is calculated, and the ignition timing of a present ignition cycle is corrected by using the calculated ratio.

Abstract: A desired value of ignition timing and a correction value therefor are calculated at a timing corresponding to a first specific one of sensed predetermined crank angle positions of each cylinder of the engine. Data indicative of the calculated desired value of ignition timing are set in a counter to start counting based upon the set data at a second specific one of the predetermined crank angle positions, subsequent to the first specific one, so that the ignition takes place upon completion of the counting. When it is determined from the calculated desired value of ignition timing whether the ignition is to be effected after a third specific one of the predetermined crank angle positions, subsequent to the second specific one, the data set in the counter is updated to the calculated correction value, at the third specific one of the predetermined crank angle positions.

Abstract: An ignition timing control method for an internal combustion engine, which controls the ignition timing of a mixture to be supplied to the engine in a feedback manner responsive to the difference between the actual engine speed and the desired idling speed. When it is determined that the engine is in a predetermined idling region and the engine temperature is above a predetermined value, the ignition timing is retarded by a predetermined amount, and the ignition timing thus retarded is corrected by a correction value calculated by multiplying the difference between the actual engine speed and the desired idling speed by a predetermined coefficient, to thereby control the ignition timing to the ignition timing value thus corrected. The ignition timing feedback control is inhibited when the voltage at a predetermined input terminal of a central processing unit is at a predetermined input level.

Abstract: An ignition timing control method for an internal combustion engine wherein a plurality of correction values for ignition timing are stored in memory means beforehand as a function of an output voltage from a variable voltage creating means which is humanly adjustable and the rotational speed of the engine. The output voltage from the variable voltage creating means and the rotational speed of the engine are detected, and one of the correction values is read, which corresponds to the detected output voltage and the detected rotational speed of the engine. Then, the ignition timing is corrected by the use of the read one correction value. Further, a value of a parameter indicative of load on the engine is detected, and the ignition timing control is executed when the detected value of the parameter is above a predetermined value. Alternatively, in place of the correction values, address values are stored in memory means.

Abstract: A method of controlling ignition timing of an internal combustion engine when an abnormality develops in a system for sensing a reference crank angle position of a crankshaft of the engine, in which the timing at which an ignition coil starts and stops conducting is controlled on the basis of a first pulse signal generated once per at least two revolutions of the crankshaft at a predetermined crank angle position associated with a particular cylinder of the engine, a second pulse signal indicative of a predetermined reference crank angle position of the crankshaft for each cylinder, and a third pulse signal indicative of a predetermined angular position of the crankshaft.

Abstract: A test system for simultaneously testing a plurality of logic circuits first sets them all to an initial state before beginning testing. The faulty logic circuits which cannot be set to the initial state can be identified, and the testing of the others can proceed, even after only one cycle of attempting to initialize all the logic circuits. If all the logic circuits are faulty, the further testing can be prevented.

Abstract: A quicklime is treated by CO.sub.2 gas so as to form a CaCO.sub.3 film on the surface of the particle thereof. It serves to prevent moisture absorption so that a steel making process, especially for the production of low hydrogen steel, can be done very effectively with low cost by the use of this CO.sub.2 -treated lime.