JP6532168B2 - Double reversal fan - Google Patents

Description

  The present invention relates to a counter-rotating fan in which an upstream fan and a downstream fan rotate in different directions.

  As an axial flow type fan or blower, there is known one in which an upstream fan and a downstream fan are arranged with the center of rotation axis aligned in the axial flow direction. Such counter-rotating fans and the like cancel out the counter torque when the flow of air is concentrated in the axial flow direction due to the rectification effect compared to the case where a single fan rotates. There are advantages, such as can be done. By utilizing the advantages, downsizing of the fan, power saving, and quietness can be achieved.

  The inventor of the present invention has an open-type counter-rotating fan that also sucks air from between the upstream fan and the downstream fan in order to improve the performance of a fan that blows air from the outside of the PC as a peripheral device of the PC. Have been proposed (patent documents 1 to 3).

  Furthermore, the inventor of the present invention can construct two motors, which are used as a power source of this type of counter-rotating fan, with the same function or effect similar to that of one motor. We examined a new counter-rotating fan.

  In addition, although what drives each fan using a gear train as a reverse rotation type fan using one motor may be considered, it is unpreferable from the point of a cost increase, noise generation, etc. Therefore, the newly proposed counter-rotating fan aims to obtain a counter-rotating fan with a simple configuration and high energy efficiency without using the above-described gear train while using one motor. It is

  That is, this counter-rotating fan includes an upstream fan on the rear side and a downstream fan on the front side, which are arranged with their rotational axes aligned in the axial direction, and the upstream fan and the downstream fan rotate in different directions. In the double-reversal fan, the upstream fan on the rear side is rotationally driven by a motor, and the downstream fan on the front side is rotatably provided on the rotation shaft, and the upstream fan on the rear side rotates When this wind power causes the front downstream fan to rotate in the opposite direction, furthermore, this counter-rotating fan sucks in air from the rear in the axial direction, and between the upstream fan and the downstream fan. The air was also sucked from the

Patent No. 5709921 gazette Patent No. 5726107 gazette Patent No. 5749195 gazette

  In the above-described counter-rotating fan, since the upstream fan on the rear side is rotationally driven by the motor, a swirling flow is generated in addition to the straight flow. The swirling flow is wasted because the swirling component becomes centrifugal force and diffuses in the radial direction. Therefore, this is returned by the downstream fan on the front side and converted into a straight component, and as a result, the efficiency of the air blowing can be improved. This is a wind loss that causes air flow loss, that is, a whirlwind (wind that is only rotating around the fan) generated by the rotation of the fan and a wind blown out in the centrifugal force direction (lateral direction), the rotation of the downstream fan on the front side Thus, it is possible to improve the air blowing efficiency of the air blown in the axial direction from the upstream fan on the rear side.

  Although this counter-rotating fan can improve a certain air blowing efficiency, the following points have been studied as future issues. That is, in the case of such a method of driving the upstream fan on the rear side, since there is a rotation-free downstream fan on the front side, the wind from the upstream side (rear side) is blocked and the air is blown as the rotational speed is increased. The point is that the loss will increase.

  Therefore, the present invention, in this type of counter-rotating fan, inherits a simple configuration and high energy efficiency counter-rotating fan that drives one of the two fans, and further, the fan efficiency is further enhanced. It is an object of the present invention to obtain a counter-rotating fan capable of improving the

The invention described in the first claim of the present application is described between the front cover (200) provided with the straightening vane (200a) and the grill cover (300) on the rear side, with the reference numerals used in the embodiments. And an upstream fan (110) on the rear side and a downstream fan (120) on the front side, which are arranged with their rotational axes aligned in the axial direction, and the upstream fan (110) and the downstream fan (120) are different from each other In the counter-rotating fan (1) rotating in the direction
The upstream fan (110) is rotatably provided on the rotation shaft, and the downstream fan (120) is rotationally driven by a motor M.
The upstream fan (110) has a blade shape formed into a winding curve (involute curve) and is disposed close to the downstream fan (120).
The upstream fan (110) reverses under negative pressure generated when the downstream fan (120) rotates to generate a swirling flow,
The swirling flow of the upstream fan (110) reduces the swirling component of the downstream fan (120) to increase the straight component of the downstream fan (120), and the remaining swirling component of the downstream fan (120) The straightening direction (200a) of the front cover (200) is configured to be straightened .
The hub (110a) of the upstream fan (110) is disposed behind the hub (120a) of the downstream fan (120), and the motor M is accommodated behind the hub (110a) of the upstream fan (110). The case body (400a) of the case (400) is mounted, and further, the shaft S of the motor M is protruded from the front end of the case body (400a), and the shaft S is a hub (110a) of the upstream fan (110). ) And fixed to the hub (120a) of the downstream fan (120) .

In the invention described in claim 2 of the present application, the downstream fan (120) according to claim 1 , wherein the hub (110a) and the tip side portion of the blade (111) when the upstream fan (110) rotates It is a counter-rotating electric fan (1) characterized in that it is inserted in a non-contact manner into a gap (122) on the rear side formed by the blade (121) when the wheel rotates.

  According to the invention described in the first aspect of the present invention, the rear upstream fan (110) is rotatably provided on the rotation shaft, and the front downstream fan (120) is rotationally driven by the motor M. Since the upstream fan (110) disposed close to (120) is formed into a winding curve (involute curve) shape, the negative pressure generated when the downstream fan (120) rotates reverses the swirling flow The swirling flow of the upstream fan (110) reduces the swirling component of the downstream fan (120), thereby increasing the rectilinear component of the downstream fan (120), and the remaining portion of the downstream fan (120). Since the turning component is straightened in the straight direction by the straightening vane (200a) of the front cover (200), an excellent straightening effect can be obtained.

  Furthermore, since the upstream fan (110) is provided on the windward side of the motor-driven downstream fan (120), the upstream fan (110) is provided in the axial direction as compared to that provided downstream. The air flow loss of the air flow can be reduced as much as possible.

Also , the case body (220a) of the case (220) containing the motor M is mounted inside the hub (110a) of the upstream fan (110), and the shaft S of the motor M is protruded from the front end of the case body (220a) And the shaft S is fixed to the hub (120a) of the downstream fan (120) by penetrating the hub (110a) of the upstream fan (110). The spacing can be reduced.

Furthermore, as in the invention described in claim 2 of the present application, when the upstream fan (110) rotates, the downstream side fan (120) rotates at the tip side portion of the hub (110a) and the blade (111). The air gap (122) on the rear side formed by the blade (121) in a non-contacting manner, that is, the hub (110a) and the blade (111) of the upstream fan (110) as much as possible Since it can be made close to the downstream fan (120), further downsizing can be achieved in a counter-rotating fan having two fans.

1 is a front perspective view of a counter-rotating fan according to an embodiment of the present invention. FIG. 2 is a longitudinal side view of a counter-rotating fan according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of a counter-rotating fan according to an embodiment of the present invention. FIG. 2 is a side view showing a front cover, a downstream fan, and an upstream fan in order according to an embodiment of the present invention. It is a side perspective view which shows the front cover, the downstream fan, and the upstream fan in order in connection with the Example of this invention. It is the figure which looked at the upstream fan concerning the Example of this invention from the back side.

  Hereinafter, an embodiment of the present invention will be described based on the drawings. The counter-rotating electric fan 1 of this example is a small electric fan driven by using a USB of a personal computer or a dry cell as a power supply. The counter-rotating fan 1 includes a rear upstream fan 110 disposed between the front cover 200 provided with the straightening vanes 200 a and the grill cover 300 on the rear side, with the rotational axis aligned in the axial direction. A front side downstream fan 120 is provided.

  In the present embodiment, the downstream fan 120 is rotated by the motor M. The upstream fan 110 is provided rotatably (rotationally free) about the rotation axis.

  When the downstream fan 120 is rotated by motor drive, the upstream fan 110 provided free of rotation is rotated following the rotation of the downstream fan 120. That is, the upstream fan 110 is configured to invert under negative pressure generated when the downstream fan 120 rotates.

  By the way, in the counter-rotating fan of the previous example, the upstream fan 110 is motor-driven, and the rotation-free downstream fan 120 is rotated by the fan style. According to this, since the wind flows in from the rear side of the motor driven downstream fan 120, it was examined whether this inflow phenomenon, that is, the phenomenon in which the rear side of the fan becomes negative pressure can not be used. According to the inventor's knowledge, by forming the blade 111 of the rotation free upstream fan 110 into a winding curve (involute curve) shape, it has been realized that the rotation free upstream fan 110 rotates well. Furthermore, when the rotation-free upstream fan 110 is considered to approach and separate from the downstream fan 120 and examined, the rotation of the upstream fan 110 is increased by causing the upstream fan 110 to approach the downstream fan 120 as much as possible. I found out.

  The rotation-free upstream fan 110 reverses under negative pressure generated when the downstream fan 120 rotates as described above. When the upstream fan 110 reverses, a swirling flow in the opposite direction to the swirling flow of the downstream fan 120 is generated. Then, the generated backward swirling flow of the upstream fan 110 reduces the swirling component of the downstream fan 120 and increases the rectilinear component of the downstream fan 120.

  Further, the remaining turning components of the downstream fan 120 driven by the motor are arranged in the straight-ahead direction by the straightening vane 200a of the front cover 200 formed in a plate shape in the air blowing direction.

  Furthermore, in this example, the hub 110a of the upstream fan 110 is disposed behind the hub 120a of the downstream fan 120, and the case main body 400a of the case 400 housing the motor M is disposed behind the hub 110a of the upstream fan 110. Further, the shaft S of the motor M is protruded from the front end of the case main body 400 a, and the shaft S is fixed to the hub 120 a of the downstream fan 120 by penetrating the hub 110 a of the upstream fan 110. Such an appropriate arrangement of the component members makes it possible to reduce the device interval in the axial flow direction, thereby making it possible to make the counter-rotating fan compact. A case cover 400b is attached to the case main body 400a of the case 400 housing the motor M from the rear (rear) side. Reference numeral 400c is a leg.

  Further, in this example, when the upstream fan 110 rotates, the tip end side portions of the hub 110a and the blade 111 are not in the gap 122 on the rear side formed by the blade 121 when the downstream fan 120 rotates. It has a structure which is inserted by contact. Here, when the downstream fan 120 rotates, the gap 122 on the rear side formed by the blade 121 is on the rear side (upstream side) of the rear end edge of the blade 121 formed by the rotation of the blade 121. It is a space site to be formed.

  As described above, when the upstream fan 110 rotates, the tip end portions of the hub 110 a and the blade 111 are fitted in the air gap 122 in a non-contact manner. As a result, it is possible to make them close to each other, and in the counter-rotating fan having two fans, further downsizing can be achieved.

  In the motor-driven downstream fan 120, the amount of air blown, the amount of noise, and the negative pressure generated depend on the number of blades 121. So, in this example, while setting the number of the blades 121 of the downstream fan 120 to four, the number of the blades 111 of the upstream fan 110 was set to seven in connection with this. This makes it possible to increase the amount of air blown to the front side, reduce the amount of noise, and optimize the negative pressure generation efficiency.

  In the counter-rotating fan 1 of this example, the downstream fan 120, the upstream fan 110, the case 400, the motor M, and the case cover 400b are incorporated between the front cover 200 and the grille cover 300, and the leg of the case cover 400b 400c is supported by the lower stand 10 so as to be adjustable in angle. A bottom plate 20, a nameplate seal 30, and a cushion 40 are attached to the base 10 in order, and a drive circuit 50 and a switch operation unit 60 are incorporated into the base 10 (see FIG. 3). In addition to the ON / OFF function, the switch operation unit 60 can adjust the air volume by changing the voltage.

  In the counter-rotating fan 1 of this example configured as described above, the downstream fan 120 is rotated by the ON operation of the switch operation unit 60, and the upstream fan 110 is rotated by the negative pressure generated by the rotation of the downstream fan 120. To turn. Since the swirling of the upstream fan 110 rotates in the direction that cancels the swirling flow of the downstream fan 120, the swirling component of the wind generated from the downstream fan 120 decreases, and a highly linear flow of wind can be obtained. Further, the remaining rotation component of the downstream fan 120 is straightened by the straightening vane 200 a of the front cover 200. These actions have the effect of improving the blowing efficiency in blowing compared to a counter-rotating fan that drives the upstream fan by a motor and makes the downstream fan free of rotation.

As described above, the fan of this example is extremely rationally configured as an open structure counter-rotating fan. Of course, the configuration of each part in the present embodiment can be appropriately changed in design within the technical scope described in the claims, and is not limited to that described in the embodiment.

  The counter-rotating fan according to the present invention is excellent in manufacturability and can produce an extremely excellent counter-rotating fan with low noise and high air-blowing performance, and is a small fan driven with a personal computer USB or dry cell as a power source. It is possible to utilize suitably.

Reference Signs List 1 counter-rotating fan 10 base 20 bottom plate 30 nameplate seal 40 cushion 50 drive circuit 60 switch operation unit 110 upstream fan 110a hub 111 blade 120 downstream fan 120a hub 121 blade 122 air gap 200 front cover 200a current plate 300 grille cover 400 case 400a Case body 400b Case cover 400c Leg M Motor S Shaft

Claims (2)

Between the front cover (200) provided with the straightening vanes (200a) and the grill cover (300) on the rear side, the rear upstream fan (110) and the front side are arranged with their rotational axes aligned in the axial flow direction A counter-rotating fan (1) comprising a downstream fan (120), wherein the upstream fan (110) and the downstream fan (120) rotate in different directions,
The upstream fan (110) is rotatably provided on the rotation shaft, and the downstream fan (120) is rotationally driven by a motor M.
The upstream fan (110) has a blade shape formed into a winding curve (involute curve) and is disposed close to the downstream fan (120).
The upstream fan (110) reverses under negative pressure generated when the downstream fan (120) rotates to generate a swirling flow,
The swirling flow of the upstream fan (110) reduces the swirling component of the downstream fan (120) to increase the straight component of the downstream fan (120), and the remaining swirling component of the downstream fan (120) The straightening direction (200a) of the front cover (200) is configured to be straightened .
The hub (110a) of the upstream fan (110) is disposed behind the hub (120a) of the downstream fan (120), and the motor M is accommodated behind the hub (110a) of the upstream fan (110). The case body (400a) of the case (400) is mounted, and further, the shaft S of the motor M is protruded from the front end of the case body (400a), and the shaft S is a hub (110a) of the upstream fan (110). A reverse rotation type electric fan characterized in that the through hole is fixed to the hub (120a) of the downstream fan (120) . When the upstream fan (110) rotates, the distal end side portion of the hub (110a) and the blade (111) is formed on the rear side of the blade (121) when the downstream fan (120) rotates. 2. The counter- rotating electric fan according to claim 1 , wherein the space is inserted in a non-contacting manner.

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