JPH0272699U

JPH0272699U -

Info

Publication number: JPH0272699U
Application number: JP14941188U
Authority: JP
Priority date: 1988-11-16
Filing date: 1988-11-16
Publication date: 1990-06-04

Description

[Brief explanation of drawings]

第１図は本考案の一実施例を示す構成ブロツク
図、第２図は印加電圧制御手段の一例を示す回路
図、第３図は電流のフアン２０に対する供給状
況を示す構成ブロツク図、第４図はフアンの印加
電圧と回転数の関係図、第５図は従来の電動フア
ンの冗長化システムの構成ブロツク図、第６図は
フアン停止検出回路３０の回路の一例を示す図で
ある。１０……電源、２０……フアン、３０……フア
ン停止検出回路、４０……印加電圧制御回路。 FIG. 1 is a configuration block diagram showing one embodiment of the present invention, FIG. 2 is a circuit diagram showing an example of applied voltage control means, FIG. 3 is a configuration block diagram showing the state of supply of current to the fan 20, and FIG. 5 is a diagram showing the relationship between the applied voltage and the rotational speed of the fan, FIG. 5 is a block diagram of a conventional electric fan redundancy system, and FIG. 6 is a diagram showing an example of the fan stop detection circuit 30. 10... Power source, 20... Fan, 30... Fan stop detection circuit, 40... Applied voltage control circuit.

Claims

[Claims for Utility Model Registration] (1) An electric fan comprising: a power source that supplies a current of a predetermined voltage; and a plurality of fans that are connected in parallel to the power source and whose rotational speed increases as the applied voltage increases. In the redundant system, an applied voltage control means is provided to apply a voltage reduced by a predetermined voltage drop from the voltage output from the power supply to the fans, and when all of the fans are operating normally. redundancy of an electric fan, characterized in that a voltage drop that occurs in the applied voltage control means when at least one of the fans is stopped is smaller than a voltage drop that occurs in the applied voltage control means of system. (2) The applied voltage control means includes: a first switching element to which a current output from the power source is applied to an input terminal; a control terminal directly connected to the output terminal of the first switching element; a second switching element connected to the output terminal of the first switching element via a resistor and having an output terminal for outputting a current to the fan;
a switching element, an input terminal to which a current output from the power source is applied, an output terminal connected to a control terminal of the first switching element and an input terminal of the second switching element, the first switching element; 2. The electric fan redundancy system according to claim 1, further comprising: a constant current element having a control terminal connected to a control terminal of said output terminal and maintaining a constant current output from said output terminal.