PURPOSE: To enable a pump to stop even when runaway occurs to a basic interval timer and to enable prevention of the occurrence of an unsafe mode by a method wherein the basic interval timer is employed, a timer is set on each occasion of the passage through a routine during normality at the safety processing routine of a microcomputer, and the timer is not set during abnormality.
CONSTITUTION: A microcomputer 6 first performs detection by means of a vaporizer thermistor and controls a vaporizer temperature. The microcomputer then controls an electromagnetic pump 5, a relay 43 for control, and a relay 62 for ignition and manages combustion. The fuel pump 5 is run and a basic interval timer is set. During abnormality, a pulse output is not processed and the pump 5 stops operation, and the basic interval timer is not set. The whole of a system is prevented from being brought into an unsafe state in relation to abnormality of combustion and a system and partial defective operation of a microcomputer itself in addition to runaway and malfunction of the microcomputer 6.
TOMINAGA HIROSHI
SUZUKI YASUSHI
UGAJIN TOSHIYUKI
