| 摘要 |
<p>PROBLEM TO BE SOLVED: To continuously measure the particle size distribution of metal particles by providing a means outputting a short-circuit signal when electrodes are short-circuited and restoring a short-circuit state when the short-circuit signal is continued for a predetermined time or more. SOLUTION: A short-circuit detection means 10 outputs a short-circuit signal to an electrode storing means 30 when a short-circuit state is generated between electrodes 2a, 2b. The restoring means 30 outputs an operation command to a switch 59 when the short-circuit signal continuous for a predetermined time or more and a parallel circuit of resistors 35, 5 is formed. The resistor 5 is set so as to have a resistance value larger than the resistance value Ro between the electrodes obtained when metal particles are attracted and the resistor 35 is set so that the resistance value thereof is lower than that of the resistor 5 but larger than Ro. In such a case that metal particles attracted between the electrodes 2a, 2b are not scattered, when the short-circuit signal from the short-circuit detection means 10 is continuously outputted for a predetermined time or more, the electrode restoring means 30 fonts a parallel circuit of the resistors 35, 5. As a result, a large current of a predetermined value or more flows to the resistor 35 to scatter metal particles. By this constitution, a short-circuit state is restored and the particle size distribution of metal particles can be continuously measured.</p> |
