Patent ID: 8668477
Filing Date: 2014-03-11
Classification: F04D

Abstract:
1. A series-connected fan unit, comprising: a first fan frame having a first base and a first positioning member coupled with the first base and a first insulated pressure-resistant portion extending from the first positioning member away from the first base, with the first insulated pressure-resistant portion having an end; a second fan frame connected to the first fan frame in series and having a second base and a second positioning member coupled with the second base and a second insulated pressure-resistant portion extending from the second positioning member away from the second base; a first motor disposed in the first base and having a first circuit board coupled with the first positioning member and intermediate the end of the first insulated pressure-resistant portion and the first positioning member, with the first pressure-resistant portion surrounding the first circuit board; a second motor disposed in the second base and having a second circuit board coupled with the second positioning member and intermediate the end of the second insulated pressure-resistant portion and the second positioning member, with the second pressure-resistant portion surrounding the second circuit board; two impellers respectively coupled with the first motor and the second motor; an insulation area between the first circuit board and the second circuit board, wherein the first and second circuit boards are spaced from the ends of the first and second insulated pressure-resistant portions to form the insulation area; and a gap between the ends of the first and second insulated pressure-resistant portions.