JPH02168879A - Fault detector for fan - Google Patents

Abstract

PURPOSE:To enable the fault of a fan to be detected by detecting rotation pulse signal from fan bodies, to generate the output of fan selection or non- selection signal, and by detecting the presence or absence of the pulse of a signal line in the state of non-selection signal output, to check the working of a selecting means. CONSTITUTION:By a selecting means in fan bodies U1-Ui, selection signal fed via a selection line L1 is received, and specified fans 11-22 are selected, and rotation pulse from the selected fans 11-22 is fed back to a rotational frequency detecting means 31. In case that the working of the selecting means is abnormal, the fans 11-22 are not to be correctly selected. By a selection signal generating means 32, the output of non-selection signal is generated besides generating the output of the selection signal, and by a check means 33, the presence or absence of the then signal line L2 pulse is checked, and then, the abnormal working of the selecting means is detected. As a result, the fault of the fans 11-22 can be detected at the same time as the high reliability is kept.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a fan failure detection device in a system having a plurality of cooling fans for cooling equipment, and more specifically, to a fan unit having a selection means for receiving a selection signal and selecting one of the plurality of fans; and a rotation speed detector coupled to the plurality of fan units and detecting a decrease in the rotation speed of each of the fans. The present invention relates to a fan failure detection device in a system comprising a unit.

<Prior Art> In a system that uses a plurality of fans to cool a device, a decrease in the fan rotation speed causes a temperature rise within the system, causing malfunction. Therefore, in systems that require high reliability, it is necessary to constantly monitor whether multiple fans are working properly.

On the other hand, it is required that as few signal lines as possible be used to connect the fan installed in the system and its monitoring device. For this purpose, a fan unit consisting of a plurality of fans is provided, a selection means for selecting one of the plurality of fans is provided in the fan unit, and a selection signal is sent thereto from the monitoring device side.

<Problems to be Solved by the Invention> However, in conventional devices having such a configuration, if the selection means in the fan unit fails, a particular fan will not be selected forever, resulting in the inconvenience that it will no longer be possible to monitor it. .

The present invention has been made in view of the above points, and its purpose is to realize a fan failure detection device that has a simple configuration and is capable of monitoring failures of selection means provided in a fan unit. There is a particular thing.

Means for Solving the Problems> The present invention for solving the problems described above includes a fan unit having a plurality of rotary pulse output type fans and a selection means for receiving a selection signal and selecting a corresponding fan; A system comprising a rotation speed detection unit coupled to a fan unit via a signal line and a selection line that sends a selection signal for selecting a plurality of fans, the system comprising: a rotation speed detection unit that transmits a signal from the fan unit into the rotation speed detection unit; rotation speed detection means for detecting a rotation pulse signal sent through the line; selection signal generation means for outputting a selection signal for selecting each fan and a non-selection signal for not selecting any fan to the selection line; The apparatus is constructed by providing a check means for detecting the presence or absence of a pulse on a signal line while outputting a selection signal and checking the operating state of the selection means.

Function> The selection means in the fan unit selects a predetermined fan upon receiving the selection signal sent via the selection line, and sends rotation pulses from the selected fan back to the rotation speed detection means. If the selection means malfunctions, the fan will not be selected correctly. The selection signal generating means outputs a non-selection signal in addition to outputting a selection signal, and the checking means detects an abnormal operation of the selection means by checking the presence or absence of a signal line pulse at this time.

<Example> Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, Ul, U2...Ui are a plurality of fan units, and each unit has four rotating pulse output type fans 11, 12, 13, 14...
is the provision. DB is a connection terminal, and each fan unit U1, U2, Ui is connected to this connection terminal DB by a selection line L1 that sends a signal for selecting a fan and a signal line L2 that sends a rotation pulse. , H.U.
is a rotation speed detection unit, which is connected to each fan unit U1 to Ui via a connection terminal DB.

In the rotation speed detection unit HU, 31 indicates each fan unit tJ1. rotation speed detection means for detecting a rotation pulse signal sent from the selected fan U2...;
Reference numeral 32 denotes a selection signal generating means for outputting a fan selection signal and a non-selection signal that does not select any fan.
Further, as a non-selection signal, a mode is provided in which a 0.times.voltage is output.

33 is in a state where a non-selection signal is output, and each signal line L2
This check means detects the presence or absence of the upper pulse and checks the operating state of the selection means provided in the fan unit.

34 is a microprocessor (CPU), which is coupled to the rotation speed detection circuit 31, selection signal generation means 32, and checking means 33, and controls these in an integrated manner, and also determines whether there is a failure of the fan or abnormal operation of the selection means.635 is a memory. , 36 are means for warning and displaying when a failure is detected.

FIG. 2 is a configuration and connection diagram showing the configuration of a single fan.

When voltage V is applied to terminals T1□T2, the fan rotates,
A pulse corresponding to this rotational speed is transmitted from the terminal T3 to the signal line L2.
It is structured so that you can get the above.

FIG. 3 is a block diagram showing the internal configuration of one fan unit. Comparators 41 to 44 compare different set voltages E1 to E4 with selection signals, and only one of the comparators is selected and its output is inverted. 45
~48 is also a comparator, and the fan 11 corresponding to one input terminal
The rotation pulses from 1 to 14 are applied, and the selected outputs from the corresponding comparators 41 to 44 are applied to the other input terminal, and the rotation pulses from the corresponding fan are transmitted through the comparators selected by the selected outputs. is configured so that it is output to the signal line L2. Here, each of the comparators 41 to 48 constitutes a selection means 4 that selects a specific fan according to a selection signal.

The operation of the apparatus configured in this way will be explained next.

First, the rotation speed detection unit HU sends a selection signal to the selection signal generation means 3 for selecting the fan whose rotation speed is to be detected.
1 and connect it to the connection terminal DB and selection line L.
1 to fan units U1 to Ui.

On the fan unit side, upon receiving the selection signal, the corresponding fan is selected, and a rotation pulse signal from the fan is sent to the rotation speed detection means 31 via the signal line L2.

Note that here, each fan unit Ul is selected by the selection signal.
, U2. It is assumed that one fan is selected at the same time within Ui, and rotation pulses from the fans are applied in parallel to the rotation speed detection means 31 and the checking means 33 via separate signal lines L2.

When the detection of rotation pulses from one fan in the fan unit is completed, a selection signal for selecting the next fan is output, and the above operation is repeated again.

By performing such an operation, rotation pulses from all the fans in each fan unit can be detected.

Here, if the selection means 4 in the fan unit malfunctions, all the fans in the fan unit or a specific fan will not be selected at any time.

Therefore, the selection signal generating means 32 outputs a non-selection signal at a fixed period, for example, and the checking means 33 checks whether a pulse signal is present on each signal line at this time. If a pulse signal is present, the pulse is being output even though none of the fans are selected, so it is determined that the selection means 4 is malfunctioning, and an alarm is output.

FIG. 4 is a flowchart showing an example of the operation performed by the microprocessor 34.

First, a non-selection signal is output from the selection signal generating means 32 to each fan unit l- (step 1).

Next, the checking means 33 checks the presence or absence of a pulse signal on each signal line. If it is detected here that there is no pulse signal, the selection means 4 determines that the operation is normal and moves to step 4.

In step 2, when a pulse is detected, the operation of the selection means is determined to be abnormal, and an error code indicating this is set (step 3). This operation is performed for all fan units, and if an error code is set, the address of the corresponding fan unit is displayed as being abnormal in the selection means (step 5).

In addition, in the above explanation, the selection signal for selecting each fan is a voltage or signal of different magnitude, thereby reducing the number of selection lines. , a digital signal of several bits or a number of pulses (serial pulses) may be sent.

<Effects of the Invention> As described in detail above, according to the present invention, it is possible to detect abnormal operation of the selection means in a fan unit having multiple fans, and to detect fan failures while maintaining high reliability. It can be detected while

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is a conceptual diagram showing the configuration of the fan, FIG. 3 is a block diagram showing the internal configuration of the fan unit, and FIG. 4 is a flowchart showing the operating procedure performed by the microprocessor. Ul, U2~Ut...Fan unit, HU...Rotation speed detection unit, DB...Connection terminal, 11.12~In...Fan, 31...Rotation speed detection means, 32... Selection signal generating means, 33... Checking means, 34... Microprocessor, 35... Memory,

Claims (1)

[Scope of Claims] A fan unit having a plurality of rotating pulse output type fans, a selection means for receiving a selection signal and selecting a corresponding fan, and a signal line for the plurality of fan units and a means for selecting the plurality of fans. A system comprising a rotation speed detection unit coupled via a selection line that sends a selection signal, and a rotation speed detection unit that detects a rotation pulse signal sent from the fan unit via the signal line into the rotation speed detection unit. a detection means; a selection signal generation means for outputting a selection signal for selecting each fan and a non-selection signal for not selecting any fan to a selection line; and checking means for detecting the operating state of the selection means.