JPH0539661Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a cooling device.

[Problems that conventional technology and ideas try to solve]

Generally, in electronic devices and the like in which electronic components are mounted within a housing, it is necessary to cool the electronic components.

Conventionally, the entire interior of the housing has been cooled almost uniformly, even though each electronic component has a different amount of heat generated. Therefore, electronic components that generate a large amount of heat cannot be effectively cooled, and in order to cool the electronic components, the fan must be rotated at high speed, which requires high energy.
This is a waste of energy for electronic components that do not generate much heat.

Therefore, an object of the present invention is to provide a cooling device that can reliably and effectively cool electronic components that generate a large amount of heat without wasting energy.

[Means to solve the problem]

In order to achieve the above-mentioned object, a cooling device according to the present invention is a cooling device for cooling electronic components inside a housing; a fan; a drive circuit unit that rotates the fan to draw outside air into the housing from an outside air intake port provided in the housing; a reversal signal generating section that sends a reversal signal to the drive circuit section when a predetermined temperature is reached, causes the fan to rotate in the reverse direction, and blows external air directly from the fan to the main heat generating component; It is.

[Effect]

If the temperature of the main heat generating component is below the predetermined temperature, the reverse rotation signal generator will not generate a reverse rotation signal and will not send it to the drive circuit section. In other words, the outside air is sucked into the housing from the outside air intake port, and the air inside the housing is exhausted to the outside via the fan, so that the inside of the housing is cooled almost evenly.

In addition, when the temperature of the main heat generating component exceeds a predetermined temperature, a reverse signal is sent from the reverse signal generating section to the drive circuit section, the fan rotates in the reverse direction, and external air is blown directly onto the main heat generating component. The parts are effectively cooled.

〔Example〕

Examples will be described below with reference to the drawings.

2 and 3 show an electronic device 1 in which the cooling device according to the present invention is used, and this device 1 has a large number of electronic components 3 . . . mounted in a housing 2. FIG.

The cooling device is for cooling the electronic components 3, and includes a fan 5 attached to the wall surface 4 of the housing 2, and a drive circuit section 6 (see FIG. 1) that rotationally drives the fan 5. ) and a reversal signal generating section 7 that sends a reversal signal for rotating the fan 5 in the reverse direction to the drive circuit section 6, and when the reversal signal is not sent to the drive circuit section 6, the fan 5 is driven in the forward rotation direction. Then, as shown in FIG. 2, external air enters the housing 2 from the outside air intake port 8 opened in the housing 2 as shown by the arrow, and the electronic components 3 inside the housing 2 are transported. It is discharged to the outside via the fan 5 while being cooled.
In other words, the inside of the housing 2 is cooled almost uniformly.

Therefore, the state in which the reversal signal is sent to the drive circuit section 6 means that the main heat generating component 9 of the electronic components 3...
This is when the temperature reaches a predetermined temperature. Here,
The main heat generating component 9 refers to a component that is most likely to reach a high temperature among the electronic components 3, or a component that is dangerous if abnormally heated due to overcurrent, etc., such as a power device. The fan 5 is provided on the wall surface 4 of the housing 2 near the main heat generating component 9.

Further, the drive circuit section 6 is, as shown in FIG.
For example, a three-phase unipolar drive system is used, and signals H ₁ , H ₂ , H ₃ from a position sensor (not shown) are input to the waveform processing circuit 10 .
The signals S ₁ , S ₂ , S ₃ from the coils L ₁ , L ₂ ,
A current is passed through _L3 , the motor section is driven, and the fan 5 is driven.

Next, the reversal signal generating section 7
and a comparator 12, the reference voltage V _ref
If it is below, it is considered to be a normal state, the fan 5 is rotated in the normal direction without sending a signal to the drive circuit section 6, and the reference voltage V _{ref is}
If the above is the case, it is assumed to be in an abnormal state, and a reverse rotation signal is sent to the drive circuit section 6 to cause the fan 5 to rotate in the reverse direction.

Specifically, the temperature detection sensor 11 uses a thermistor with positive characteristics, and as shown in FIGS. 2 and 3,
It is attached to the main heat generating component 9, and as shown in FIG. 4, the resistance value R _r increases as the temperature rises. Therefore, the voltage V _Tp at the location 13 shown in FIG.
The temperature characteristic of is a waveform as shown by the solid line in FIG. In addition, in FIG. 4, the broken line indicates the reference voltage V _ref
It shows. That is, at the point 14 where the reference voltage V _ref and the voltage V _Tp match, the signal A at the portion 15 (see FIG. 1) becomes Low level 1, as shown in FIG.
6 to High level 17, this High
At level 17, a reversal signal is sent, and as shown in FIG.
sucked inside.

Therefore, since the main heat generating component 9 is near the fan 5, the external air from the fan 5 is directly and intensively blown onto the main heat generating component 9, thereby effectively cooling the main heat generating component 9.

Therefore, FIG. 5 is a time chart showing the characteristics of this cooling device, and the waveform in FIG.
The waveform shows the signal A at point 15, the waveform shows the signal _H1 of the position sensor, the waveform shows the signal of the position sensor
H ₂ , the waveform represents the signal H ₃ of the position sensor, the waveform represents the signal S ₁ from the waveform processing circuit 10 , the waveform represents the signal S ₂ from the waveform processing circuit 10 , the waveform represents the signal S 2 from the waveform processing circuit 10 shows the signal _S3 from.

Note that the present invention is not limited to the above-mentioned embodiments, and design changes may be made without departing from the gist of the present invention.For example, the drive circuit section 6 may be of a three-phase unipolar type, but also of a three-phase bipolar type. etc., and the predetermined temperature of the main heat generating component 9 is
Since it depends on the temperature at which the electronic component becomes dangerous, it differs depending on the main heat generating component 9, and the predetermined temperature can be changed freely by changing the reference voltage. Furthermore, when the main heat generating component 9 reaches a predetermined temperature and the fan 5 is rotating in the opposite direction,
It is also preferable to add a circuit for outputting an alarm.

[Effect of the invention] In the cooling device according to the invention, the inside of the housing 2 is normally cooled almost uniformly, and when the main heat generating component 9 reaches a high temperature (a predetermined temperature or higher), the fan near the main heat generating component 9 cools down. External air is blown directly from the main heat generating component 9, and the main heat generating component 9 is effectively cooled without waste.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the cooling device according to the present invention, FIGS. 2 and 3 are simplified diagrams showing usage conditions, and FIG. 4 is a graph of temperature characteristics.
The figure is a graph of the temperature characteristic of the resistance value of the temperature detection sensor, Figure 4 is a graph of the temperature characteristic of voltage V _Tp , Figure 4 is a graph of the temperature characteristic of signal A, and Figure 5 is a time chart. be. 2...Housing, 3...Electronic components, 4...Wall surface, 5
... Fan, 6 ... Drive circuit section, 7 ... Reverse signal generation section, 8 ... Outside air intake port, 9 ... Main heat generating component,
11...Temperature detection sensor.

Claims (1)

[Scope of Claim for Utility Model Registration] A cooling device for cooling electronic components 3...in a housing 2, which is attached to the wall surface 4 of the housing 2 near the main heat generating component 9 of the electronic components 3... a drive circuit unit 6 that rotates the fan 5 to suck external air into the housing 2 from an outside air intake port 8 provided in the housing 2; and a temperature detection sensor 11. When the detected temperature of the main heat generating component 9 reaches a predetermined temperature, a reversal signal is sent to the drive circuit section 6, the rotation of the fan 5 is reversed, and the fan 5 is directly connected to the main heat generating component 9. A cooling device comprising: a reversal signal generating section 7 that blows outside air.