JPS62272559A - Cooling method for forcible ventilation controller - Google Patents

Abstract

PURPOSE:To reduce the size and weight of a whole forcible ventilation controller by providing a gate of shape memory alloy which opens at a predetermined temperature or higher due to the temperature rise of a cooling fin at the end or on the way of a vent passage at a part of the fin for forcibly ventilating and closes at its temperature or lower to effectively cool it by the fan of small capacity. CONSTITUTION:A heat generating electric component 1 is contained in a box 4, the cooling air passage of a controller 2 cooled by forcible ventilation of a cooling fin 31 exposed directly in the box 4 or out of the box 4 is divided to provide a gate 8 made of a shape memory alloy which opens at a predetermined temperature or higher due to the temperature rise of the fin and closes at its temperature or lower in a partial cooling air passage, thereby adjusting to increase or decrease the passage in response to the temperature rise. For example, when the controller 2 is operated at a light load and the fin 31 is low at its temperature, the gate 8 is closed, and when cooling air is fed at fast velocity as designated by an arrow with a solid line to effectively cool the component 1 so that the load is increased to cause the temperature of the fin 31 to become its predetermined temperature or higher, the gate 8 is opened to feed cooling air through all air passage, thereby wholly cooling the film 31.

Description

[Detailed description of the invention] 3. Detailed description of the invention [Technical field to which the invention pertains] The present invention relates to a cooling method for a forced draft cooling control device.

[Prior art and its problems]

The control device, which houses heat-generating electronic components like a semiconductor converter inside a box and uses forced ventilation to cool the cooling fins exposed outside the box, has the simplest structure possible and uses a small-capacity fan for effective cooling. It is desirable that the device be compact and lightweight.

In the conventional control device of this kind, as shown in FIGS. 4 to 6, a control device 2 having a heat-generating electric component 1 is attached to a common cooling body 3 and housed in a box 4, and the cooling fins 31 of the common cooling body 3 are The cooling fins 31 are exposed outside the box and covered with an air passage cover 5, and the cooling fins 31 are cooled by forced ventilation by a cooling fan 7 attached to the lower end of the air passage via a fan mounting base 6. Ta.

In this structure, the common cooling body 3 is enlarged to serve as the base of the structure and to accommodate capacity expansion, and the heat-generating components are often installed unevenly due to the layout. The entire cooling fin is cooled by a large-capacity fan, which has the disadvantage that efficient cooling is not achieved and it is uneconomical to increase the capacity of the fan or add more.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling method for a forced draft control device that eliminates the above-mentioned drawbacks, performs effective cooling using a small-capacity cooling fan, and makes it possible to reduce the size and weight of the entire device.

[Key points of the invention]

In the present invention, a shape memory alloy gate is installed at the end or in the middle of a part of the air passage of a cooling fin that performs forced ventilation, and the shape memory alloy gate opens when the temperature of the cooling fin rises above a certain temperature and closes below that temperature. The purpose is to adjust the number of cooling air passages to increase or decrease in response to the rise.

[Embodiments of the invention]

FIGS. 1 and 2 show a forced draft control device that performs cooling by the cooling method of the embodiment of the present invention, and parts indicated by the same reference numerals as in FIGS. 4 to 6 are the same parts. A control device 2 having a heat generating electric component 1 is attached to a common cooling body 3 and housed in a box body 4, and the cooling fins 31 of the cooling body 3 exposed outside the box body are covered with an airway cover 5. A cooling fan 7 is attached to the lower end via a fan mount 6. A gate 8 made of a shape memory alloy is attached to the upper end of the cooling fan of the cooling body on the side where no heat-generating electrical parts are attached, covering the air passage. When the temperature of the cooling fins rises above a certain level, the gate 8 opens as shown in FIG. 3 to allow cooling air to flow in the direction of the dotted arrow, and when the temperature falls below that temperature, the air passage is closed.

By doing this, when the control device is operating under a light load and the temperature of the cooling fins is low, the gate 8 is closed.
As shown by the solid line arrow, the cooling air flows at a high wind speed and effectively cools the heat-generating electrical components, but when the load increases and the temperature of the cooling fins exceeds a certain level, the gate 8 opens and the cooling air flows through the entire air path. to completely cool the cooling fins. The temperature of the cooling fins on the side where there are no heat-generating electrical components drops quickly due to ventilation, so when the temperature drops, the gate 8 closes. That is, the opening time of the gate 8 is short, and the cooling fins on the side where the heat-generating electrical components are located are intensively and effectively cooled. Therefore, the cooling fan can have a small capacity that can withstand overload for a short period of time. 'Also, if multiple fans are provided, more effective forced cooling can be achieved by increasing or decreasing the number of fans in accordance with the increase or decrease in the number of air passages.

The present invention can also be applied to a forced ventilation control device that blows cooling air into the inside of a box.

〔Effect of the invention〕

According to the present invention, the forced draft control device can be effectively cooled by a small-capacity fan, which has the effect of reducing the capacity of the cooling fan and reducing the size and weight of the entire device.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of a forced draft control device according to an embodiment of the present invention, Fig. 2 is a front view with a partial cross section of Fig. 1, and Fig. 3 is a detailed view of the P section in Fig. 1 when the gate is open. , Fig. 4 is a vertical sectional view of a conventional forced ventilation control device, Fig. 5 is a front view partially sectionalized from Fig. 4, and Fig. 6 is a plan view of Fig. 5. 1: Heat-generating electrical component, 2: Control device, 3: Cooling body, 4: Box, 5: Air duct cover, 6: Fan mounting base, 7: Cooling fan, 8: Gate, 31: Cooling fin. Figure 3

Claims (1)

[Claims] In a control device that stores heat-generating electrical components inside a box body and uses forced ventilation to cool cooling fins exposed directly inside the box body or outside the box body, the cooling air path is divided and a portion of the cooling air path is A forced ventilation control device characterized by having a gate made of a shape memory alloy that opens at a certain temperature and closes at a temperature lower than that, and adjusts the increase or decrease of the air passage according to the temperature rise. cooling method.