BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the technology field of cooling fan, and more particularly to a cooling fan module having functionality of blocking reverse flow of hot air and a host electronic system equipped with the forgoing cooling fan.

2. Description of the Prior Art

Nowadays, computer system has become a necessary host electronic device for use in the fields of human life and industry. Conventionally-used computer systems include: desk computer, laptop computer, all-in-one computer, industrial computer, server computer, and video game console. In addition, it is known that each of the forgoing computer systems certainly equipped with at least one cooling fan, and the cooling fan is adopted for achieving a heat dissipation of electronic chips and/or modules that are accommodated in a computer case of the computer system. It is worth explaining that, owing to the fact that each of the high-technology applications of space exploration, petroleum exploration, meteorological observation, cloud computing, and video game streaming service has a high-performance requirement on computing speed of the computer system, the computer system is therefore designed to have a complex circuit structure consisting of at least one host electronic module and other necessary electronic chips and/or components. In such case, how to well develop a high efficiency heat dissipation module for use in the forgoing computer system having complex circuit structure hence becomes a very important issue.

In conventional, thermal design engineers commonly achieve the enhancement and/or efficiency of the heat dissipation of one specific computer system by disposing several cooling fans in the specific computer system's computer case simultaneously. However, in case of one of the several cooling fans failing to work normally, negative pressure effect would make the hot air exhausted out of the computer case by other normally-working cooling fans reversely flow into the computer case through the malfunction cooling fan. Accordingly, China patent publication No. CN101568249A discloses a wind direction limiting device for use in a cooling fan module that is applied in an electronic device.FIG. 1andFIG. 2respectively show a first stereo diagram and a second stereo diagram of the wind direction limiting device.

The cooling fan module consisting of N number of fan units11′ that are disposed in a computer case2′, and the wind direction limiting device comprises: N number of rotary rods12′, 2N number of blocking plates13′, and N−1 number of stop members14′. In which, each of the N number of rotary rods12′ is disposed in the computer case2′, and is correspondingly adjacent to each of the N number of fan units11′. FromFIG. 1, it is understood that, each of the N number of rotary rods12′ is pivotally connected with two blocking plates13′. In addition, each of the N number of rotary rods12′ is provided with a torsion spring15′ thereon, such that two legs of the torsion spring15′ respectively contact with the blocking plates13′, so as to utilize a torque of the torsion spring15′ to make the two blocking plates13′ be relatively opened by taking the rotary rod12′ as a rotary center. In such case, external air that flows through the malfunction cooling fan unit11′ is blocked by the two relatively-opened blocking plates13′, thereby failing to continuously flow into the computer case2′. On the contrary, asFIG. 2shows, when the cooling fan units11′ all work normally, hot air producing by electronic chips and/or components is exhausted out of the computer case2′ by the cooling fan units11′. In the meantime, flow of the hot air (i.e., hot air flow) needs to overcome the torque of the torsion spring15′ in order to make the two blocking plates13′ be relatively closed by wind blowing, thereby making the hot air in the computer case2′ be successfully exhausted out.

After put the wind direction limiting device of China patent publication No. CN101568249A into practice for a long time, thermal design engineers have eventually found that the forgoing wind direction limiting device exhibits a main drawback in practical use. That is, the hot air flow is generated in case of the cooling fan unit(s)11′ works normally, and the hot air flow needs to overcome the torque of the torsion spring15′ for making the two blocking plates13′ be relatively closed by wind blowing, in order to make the hot air in the computer case2′ be successfully exhausted out.

From above descriptions, it is understood that there is still room for improvement in the conventional cooling fan(s). In view of that, inventors of the present application have made great efforts to make inventive research and eventually provided a cooling fan module having functionality of blocking reverse flow of hot air and a host system equipped with the forgoing cooling fan.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to disclose a cooling fan module having functionality of blocking reverse flow of hot air. The cooling fan module having functionality of blocking reverse flow of hot air is for application in a case of a host electronic system, and consists of a fan unit and an air flow blocking unit. In which, the air flow blocking unit comprises a left-side plate, a left-side support pole, a left-side air flow blocking plate, a right-side plate, a right-side support pole, a right-side air flow blocking plate, and a stop member. By such arrangement, the left-side air flow blocking plate and the right-side air flow blocking plate are blown by an air flow that flows from outside environment into the case through the fan unit that is in a malfunction state, so as to rotate by respectively taking the left-side support pole and the left-side support pole as a rotary center thereof. Consequently, the left-side air flow blocking plate and the right-side air flow blocking plate are stopped rotating by the stop member, such that the air flow is blocked, by the two air flow blocking plates, from being entering the case.

It is worth further explaining that, the forgoing air flow blocking unit is particularly designed for making both the left-side air flow blocking plate and the right-side air flow blocking plate can be easily blown to rotate by the air flow that flows from outside environment into the case through the fan unit that is in a malfunction state, without using any auxiliary mechanism(s). Thus, the cooling fan module having functionality of blocking reverse flow of hot air proposed by the present invention includes several advantages of simple structure, easy to be applied in a computer system, and low wind resistance.

For achieving the primary objective of the present invention, an embodiment for the cooling fan module having functionality of blocking reverse flow of hot air is provided, comprising:a fan unit adopted for being disposed in a case that accommodates s at least one electronic chips and at least one electronic components; andan air flow blocking unit, being disposed near to a wind-inletting side of the fan unit, and comprising:a left-side plate, being disposed near to the wind-inletting side of the fan unit, so as to face the wind-inletting side by one of two vertical sides thereof;a left-side support pole, being connected to another one vertical side of the left-side plate;a left-side air flow blocking plate, having at least one first pivotal connection portion, and being pivotally connected to the left-side support pole through the at least one first pivotal connection portion;a right-side plate, being disposed near to the wind-inletting side of the fan unit, so as to face the wind-inletting side by one of two vertical sides thereof; wherein there is a first spacing distance between the right-side plate and the left-side plate, and the first spacing distance being smaller than or equal to a width of the fan unit;a right-side support pole, being connected to another one vertical side of the right-side plate;a right-side air flow blocking plate, having at least one second pivotal connection portion, and being pivotally connected to the right-side support pole through the at least one second pivotal connection portion; anda stop member, being disposed at a center position between the right-side plate and the left-side plate; wherein there is a second spacing distance between the stop member and the fan unit, and the second spacing distance being smaller than or equal to a width of the left-side plate;wherein in case of the fan unit working normally for driving a hot air that is generated by the at least one electronic chip and/or the at least one electronic component to flow out of the case through the fan unit, a first air flow being produced so as to blow the left-side air flow blocking plate and the right-side air flow blocking plate, thereby consequently making a first included angle be formed between the left-side plate and the left-side air flow blocking plate, and being formed the right-side plate and the right-side air flow blocking plate;wherein when the fan unit fails to work normally or is in a malfunction state, a negative pressure effect makes an external air flow into the case through the fan unit, such that a second air flow is produced so as to blow the left-side air flow blocking plate and the right-side air flow blocking plate, thereby consequently making a second included angle be formed between the left-side plate and the left-side air flow blocking plate, and being formed the right-side plate and the right-side air flow blocking plate;wherein the second included angle is greater than the first included angle.

Moreover, an embodiment for a host electronic system is also provided in the present invention, comprising a case, at least one electronic chip, and at least one electronic component; wherein it is characterized in that the host electronic system further comprises the forgoing cooling fan module having functionality of blocking reverse flow of hot air.

In one practicable embodiment, the forgoing host electronic system is selected from the group consisting of server computer, industrial computer, cloud computing system, video game console, desk computer, laptop computer, and all-in-one computer.

In one practicable embodiment, the forgoing air flow blocking unit further comprises:a top plate, being connected to one of two horizontal sides of the left-side plate and one of two horizontal sides of the right-side plate by one surface thereof; anda bottom plate, being connected to another one horizontal side of the left-side plate and another one horizontal side of the right-side plate by one surface thereof.

In one practicable embodiment, the forgoing air flow blocking unit further comprises:a first extension plate, being connected to the left-side air flow blocking plate, wherein there is a bend angle between the first extension plate and the left-side air flow blocking plate; anda second extension plate, being connected to the right-side air flow blocking plate, and wherein there is also the bend angle between the second extension plate and the right-side air flow blocking plate.

