JP2013170505A - Contra-rotating type blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reasonably structured open architecture contra-rotating type blower.SOLUTION: There is provided a contra-rotating type blower which includes a first impeller 110 located on an upstream side and a second impeller 120 located on a downstream side, which are arranged in the axial flow direction with both the rotational axes aligned, a first motor 210 for rotating the first impeller, a second motor 220 for rotating the second impeller, and a guard 300 enclosing the first impeller and the second impeller and in which the first impeller and the second impeller rotate in the directions opposed to each other. When revolution speeds of the first and second impellers are defined as X, Y, respectively; the diameters of the first and second impellers are defined as L1, L2, respectively; and the numbers of blades of the first and second impellers are defined as A, B, respectively, the relations of X>Y, L1<L2, and A<B are satisfied.

Description

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

  As an axial-flow type blower, as disclosed in Patent Documents 1 to 5, a fan in which an upstream impeller and a downstream impeller are arranged with the rotation axis center aligned in the axial flow direction is known. . Compared with a rotating single impeller, such a counter-rotating blower cancels counter torque, because the flow of wind concentrates in the axial flow direction due to the rectification effect, and the air volume to the cooling target increases. There are advantages such as being able to. By utilizing the advantage, it is possible to reduce the size, power consumption, and silence of the blower.

Japanese Patent No. 3953503 Japanese Patent No. 3959359 Japanese Patent No. 4128194 JP 2008-121440 A JP 2011-58420 A

  As the counter-rotating blower, one used as an air cooling device provided inside a personal computer is well known. In that case, normally, the upstream impeller and the downstream impeller are arranged inside the duct. That is, it has a closed structure in order to obtain a static pressure. In contrast, the inventor of the present application has an open structure that sucks air from between an upstream impeller and a downstream impeller in order to improve the performance of a blower that blows air from the outside of the personal computer as a peripheral device of the personal computer. A heavy reversing blower was proposed. And after the earnest examination, it came to the identification of a very excellent structure, and achieved this invention.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a counter-rotating blower with an open structure that is rationally configured.

  The invention described in claim 1 of the present application includes an upstream first impeller and a downstream second impeller that are arranged with the rotation axis center aligned in the axial direction, and a first motor that rotates the first impeller. A counter-rotating mechanism comprising: a second motor that rotates the second impeller; and a guard that surrounds the first impeller and the second impeller, wherein the first impeller and the second impeller rotate in different directions. In the air blower, the rotation speed of the first impeller is X, the rotation speed of the second impeller is Y, the diameter of the first impeller is L1, the diameter of the second impeller is L2, and the first impeller When the number of blades is A and the number of the blades of the second impeller is B, they are configured to satisfy the relationship of X> Y, L1 <L2, and A <B. It is.

  The invention described in claim 2 of the present application is that in claim 1, when the width of the blade of the first impeller in the axial flow direction is W1, and the width of the blade of the second impeller is W2, they are W1 It is a counter-rotating blower having a configuration in which the relationship> W2 is established.

  According to the present invention, the configuration of an open structure counter-rotating fan is reliably rationalized. The concept will be described below.

  The counter-rotating blower is superior in terms of blowing efficiency in that the rotation speed of the first impeller on the upstream side is larger than the rotation speed of the second impeller on the downstream side. However, using a combination of the first motor and the second motor having different specifications is not a desirable configuration from the viewpoint of cost performance in design and manufacturing.

  Therefore, the inventors of the present application devise the structures of the first impeller and the second impeller when the first motor and the second motor are the same type of motor having the same specifications, and the first motor and the second motor are driven with the same voltage. It was decided.

  The first motor and the second motor only have to have the rotation speed and torque during driving within the allowable range of the appropriate load. As conditions, if the area of the blade acting on the air increases, the torque increases and the rotational speed decreases. That is, as the impeller diameter increases, the rotational speed decreases. As the number of blades increases, the rotational speed decreases. Further, when the width of the impeller blade with respect to the axial flow direction is increased, the rotational speed is decreased.

  Here, in consideration of increasing the air volume by sucking air from the open structure, that is, between the first impeller and the second impeller, the diameter L2 of the second impeller is set larger than the diameter L1 of the first impeller. did. In consideration of the air flow and the like, considering that the diameter L2 of the second impeller is larger than the diameter L1 of the first impeller, the number B of blades of the second impeller is larger than the number A of blades of the first impeller. Set. Then, the rotational speed X of the first impeller is relatively larger than the rotational speed Y of the second impeller. According to such a structure, it becomes possible to raise the ventilation efficiency of a counter rotating type blower.

  Further, under the condition that the rotational speed X of the first impeller is larger than the rotational speed Y of the second impeller, the blade width W1 of the first impeller in the axial flow direction is made larger than the blade width W2 of the second impeller. Largely set. That is, this is a device for increasing the diameter L2 of the second impeller. According to such a configuration, air can be more actively sucked from between the first impeller and the second impeller. The structurally balanced design improves air blowing efficiency.

  The inventor of the present application has repeated trial manufacture and verification in order to obtain an excellent open structure counter rotating fan, and has completed the present invention. The effectiveness of the configuration of the present invention has been confirmed by comparative experiments with prototypes under different conditions.

  According to the present invention, it is possible to obtain a counter-rotating blower having an open structure that is rationally configured.

1 is a front view of a counter-rotating blower according to an embodiment of the present invention. 1 is a side view of a counter-rotating blower according to an embodiment of the present invention. 1 is a side sectional view of a counter-rotating blower according to an embodiment of the present invention. It is explanatory drawing of a 1st impeller according to the Example of this invention, (a) is a front view, (b) is a side view, (c) is a rear view. It is explanatory drawing of a 2nd impeller according to the Example of this invention, (a) is a front view, (b) is a side view, (c) is a rear view. It is explanatory drawing of the 1st impeller and the 2nd impeller concerning the Example of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. The counter-rotating blower 1 of this example shown in FIGS. 1 to 6 is a small blower that is driven by using a USB of a personal computer as a power source. This counter-rotating blower 1 includes an upstream first impeller 110 and a downstream second impeller 120 that are arranged with the rotation axis center aligned in the axial direction, and a first motor 210 that rotates the first impeller 110. A second motor 220 that rotates the second impeller 120, and a guard 300 that surrounds the first impeller 110 and the second impeller 120, and the first impeller 110 and the second impeller 120 rotate in different directions. It has a configuration. The guard 300 is a lattice-like or net-like cover, and the counter-rotating blower 1 of this example has an open structure in which air is also sucked from between the first impeller 110 and the second impeller 120. In addition, the black arrow in FIG. 2 has shown the flow of air. 4 indicates the rotation direction of the first impeller 110, and the white arrow in FIG. 5 indicates the rotation direction of the second impeller 120.

  The first motor 210 and the second motor 220 are the same type of DC motors with common specifications, and are wired in series with a 5 [V] DC power source using USB as a power source. Or you may wire in parallel. In any case, the circuit configuration is driven with the same voltage. Each impeller 110 and 120 has a hub 110a and 120a directly connected to a drive shaft of each motor 210 and 220, respectively. The hubs 110a and 120a of the impellers 110 and 120 are set to have the same diameter.

  The motors 210 and 220 and the guard 300 are mounted on a support 20 that is supported with respect to the pedestal 10 so that the angle can be adjusted. A switch 30 for switching ON / OFF of the first motor 210 and the second motor 220 is provided at an important point of the support 20 or the base 10. The switch 30 shown in the figure is capable of adjusting the air volume by changing the voltage in addition to ON / OFF. The rotation speed in the following description is a value when driving at the maximum voltage.

  In the counter-rotating blower 1 of this example, the rotational speed of the first impeller 110 is X, the rotational speed of the second impeller 120 is Y, the diameter of the first impeller 110 is L1, and the diameter of the second impeller 120 is L2. The number of blades 111 of the first impeller 110 is A, the number of blades 121 of the second impeller 120 is B, the width of the blade 111 of the first impeller 110 in the axial flow direction is W1, and the blade 121 of the second impeller 120 is When the width is W2, they are configured such that X> Y, L1 <L2, A <B, W1> W2 are satisfied.

  In this example, the rotation speed X of the first impeller 110 is 2400 [rpm], and the rotation speed Y of the second impeller 120 is 1400 [rpm]. A desirable relationship between X and Y is X / Y = 1.6 to 2.0. The practical value of X is 2000 to 4000 [rpm], and the practical value of Y is 1400 to 2000.

  The diameter L1 of the first impeller 110 is 80 [mm], and the diameter L2 of the second impeller 120 is 85 [mm]. A desirable relationship between L1 and L2 is L2 / L1 = 1.06-1.20. A practical value of L1 is 80 to 100 [mm], and a practical value of L2 is 85 to 120 [mm].

  The number A of blades 111 of the first impeller 110 is five, and the number B of blades 121 of the second impeller 120 is seven. A practical number of A is 3 to 6, and a desirable number of B is 1 to 4 more than A.

  The width W1 of the blade 111 of the first impeller 110 with respect to the axial flow direction is 21 [mm], and the width W2 of the blade 121 of the second impeller 120 is 18 [mm]. A desirable relationship between W1 and W2 is W1 / W2 = 1.16 to 1.40.

  The gap G between the blade 111 of the first impeller 110 and the blade 121 of the second impeller 120 is 14.5 [mm]. A practical value of G is 12.0 to 16.5 [mm], and a more desirable value is 14.0 to 15.0 [mm].

  According to such a configuration, it is possible to obtain an extremely excellent counter-rotating blower that is excellent in manufacturability and has low noise and high air blowing performance.

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

  The counter-rotating blower of the present invention can be suitably used as a small blower that is driven using a USB of a personal computer as a power source.

DESCRIPTION OF SYMBOLS 1 Counter-rotating type blower 10 Base 20 Support body 30 Switch 110 1st impeller 110a Hub 111 Blade 120 2nd impeller 120a Hub 121 Blade 210 1st motor 220 2nd motor 300 Guard L1 1st impeller diameter L2 2nd impeller Diameter W1 Blade width of the first impeller relative to the axial flow direction W2 Width of the blade of the second impeller relative to the axial flow direction G Distance between the blades of the first impeller and the second impeller

Claims (2)

A first impeller on the upstream side and a second impeller on the downstream side arranged with the rotation axis center aligned in the axial direction, a first motor for rotating the first impeller, and a second motor for rotating the second impeller And a counter-rotating blower in which the first impeller and the second impeller rotate in different directions, and a guard that surrounds the first impeller and the second impeller.
The rotational speed of the first impeller is X, the rotational speed of the second impeller is Y,
The diameter of the first impeller is L1, the diameter of the second impeller is L2,
When the number of the blades of the first impeller is A and the number of the blades of the second impeller is B,
The counter-rotating blower is characterized in that the relationship of X> Y, L1 <L2, A <B is established.   When the width of the blade of the first impeller with respect to the axial flow direction is W1, and the width of the blade of the second impeller is W2, the relationship of W1> W2 is established. Item 6. The counter-rotating blower according to item 1.

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