| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent shortage of melting of resin and shortage of strength from generating by raising voltage so as to return current to the state before falling, when short circuit is dissolved and resistance is increased. SOLUTION: Current is begun to be carried to a joint 1 in a state of fixing voltage by a voltage adjusting means 2. Then resistance is gradually increased accompanying temperature rise of a heating wire. When short circuit is generated during the gradual increase of resistance, the resistance value is reduced, and current measured by a current measuring means 3 is increased. When current changing rate per unit time exceeds the threshold value, a control means 4 feedback controls the voltage adjusting means 2. Hence, voltage is lowered so as to return current to the level before rising. When the second short circuit is generated, similar control is carried out. When short of one place in two places shorted is dissolved, resistance is increased by the portion, current is decreased, and when the current changing rate exceeds the threshold value, similarly the voltage adjusting means is feedback controlled, so as to return current to the level before falling.</p> |
