| 摘要 |
PURPOSE:To remove surely tar stuck to a nozzle hole without increasing the suction force of a solenoid by controlling a needle in such a manner that the nozzle hole is opened and closed with the needle plural times during the preheating period of a vaporizer. CONSTITUTION:The temp. of a vaporizer 4 is detected by a temp. sensor 7 and after the detected value is digitized by an A/D conversion circuit 20, the value is fed to a CPU 21b through an input circuit 21a. At the CPU 21b, a fixed temp. (temp. at which kerosene does not vaporize, for instance, 70 deg.C) previously memorized in a memory 21c is compared with the input data and a judgement whether the temp. of the sensor 7 is higher than 70 deg.C or not is made. In the case where the detected temp. is lower than 70 deg.C, a signal is transmitted from an output circuit 21d to a driver circuit 22 and the carrying and stopping of current to a solenoid 14 through a relay 23 are carried out two times to slide a needle 12 twice and then by the third current-carrying to the solenoid 14 a nozzle hole 11 is completely closed. Then, when it is judged that the temp. of the sensor 7 is higher than 70 deg.C, the hole 11 is closed once. |
