JP6468985B2 - Counter-rotating blower - Google Patents

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, one 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.

  Further, as the counter-rotating blower, one used as an air cooling device provided inside a case of an electric device 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 to obtain a static pressure (Patent Documents 1 and 2). 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. The heavy inversion type blower was proposed (patent documents 3 to 5).

  Among these counter-rotating blowers, the one disclosed in Patent Document 5 includes an upstream first impeller arranged downstream of the center of the rotating shaft in the axial direction and a downstream side as described in the claims. A first motor that rotates the first impeller, a second motor that rotates the second impeller, and a guard that surrounds the first impeller and the second impeller. In the counter-rotating blower in which one impeller and the second impeller rotate in different directions, the rotational speed of the first impeller is X, the rotational speed of the second impeller is Y, and the diameter of the first impeller is When L1, the diameter of the second impeller is L2, the number of blades of the first impeller is A, and the number of blades of the second impeller is B, the first motor and the second motor are When the first motor and the second motor are driven at the same voltage as the same type of motor with the same rack, they are configured such that the relationship X> Y, L1 <L2, A <B is satisfied. It is a counter-rotating blower.

  The counter-rotating blower described in Patent Document 5 includes a first impeller and a second impeller when the first motor and the second motor are motors of the same type having common specifications, and the first motor and the second motor are driven with equal voltages. The two-impeller structure was devised as follows and completed.

  That is, the first motor and the second motor need only have the rotational 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. And it becomes a structurally balanced design, and ventilation efficiency improves.

  Thus, in order to obtain a counter-rotating blower having an excellent open structure, trial production and verification were repeated, and the invention described in Patent Document 5 was completed, and this configuration is extremely effective. It has also been confirmed by comparative experiments with prototypes with different conditions.

  By the way, this type of counter-rotating blower is not known to have a rhythm-like function with “fluctuation”. In addition, in the general electric fan different from a counter rotating type blower, what is provided with the function of a rhythm style is used. These include, for example, a control device that controls a motor with a device that generates 1 / f fluctuation (Patent Document 6), or a fluctuation generator that generates a fluctuation function signal and outputs it to a control circuit (Patent Document) 7) A controller that changes the rotational speed of a DC fan motor to generate a rhythmic wind (Patent Document 8), and a temperature measuring means that measures the temperature and controls the air volume based on the height (Patent Document 8) 9) is known.

Japanese Patent No. 3993118 Japanese Patent No. 4128194 Japanese Patent No. 5709921 Japanese Patent No. 5726107 Japanese Patent No. 5749195 JP-A-5-18396 JP-A-9-88879 JP 2012-237238 A Japanese Patent Laying-Open No. 2015-86865

  Based on the knowledge obtained from the trial production and verification of the invention as described above, the applicant of the present application uses two motors that are used as power sources for this type of counter-rotating blower with the same function. The structure which can show an effect or the effect similar to it was examined, and the counter rotating type fan using one motor was proposed as mentioned above.

  In addition, although the previous invention can consider what drives each impeller using a gear train as a counter rotating type blower that uses one motor, it is not preferable from the viewpoint of cost increase and noise generation. Those using gear trains are excluded from design and development, and include a counter-rotating blower having a simpler configuration and higher energy efficiency.

  Further, in the previous invention, the function of the rhythm style is not provided. On the other hand, the electric fans described in Patent Documents 6 to 9 are not provided with a control device for generating the rhythm style, not the ON / OFF control of the motor. It is what.

  Therefore, the present invention provides a counter rotating fan that generates a straight forward wind in a counter rotating fan having a simpler configuration and higher energy efficiency without using the above gear train while using one motor. In addition to its functions, it is intended to be a counter-rotating blower that can provide a gentle, natural rhythmic wind with a simple and simple configuration consisting of simple motor ON / OFF control.

When the invention described in the first claim of the present application is described with the reference numerals used in the embodiments, the first impeller (110) on the upstream side and the downstream side of the first impeller (110) arranged with the rotation axis center aligned in the axial direction. A counter-rotating blower (1) comprising a second impeller (120), wherein the first impeller (110) and the second impeller (120) rotate in different directions,
The first impeller (110) is rotationally driven by a motor (210),
The second impeller (120) is rotatably provided on the rotating shaft, and is opposite to the rotation direction of the first impeller by the wind force of the first impeller when the first impeller (110) rotates. Non-motor driven , rotating in the direction,
The counter-rotating blower (1) sucks air from the rear in the axial flow direction and sucks air from between the first impeller (110) and the second impeller (120),
Furthermore, when the first impeller (110) and the second impeller (120) are viewed from the front in the axial flow direction, each of the first impeller (110) with respect to the total area of the blade (111) constituting the impeller When the ratio of the gap between the blades is P, and the ratio of the gap between the blades (121) constituting the impeller of the second impeller (120) is Q, the ratio of the gap between the blades is P> Q. Establish relationships so that
The first impeller (110) is intermittently driven by ON / OFF control of the motor (210) to reverse the second impeller (120), and the first impeller (110) and the second impeller ( 120) is a counter-rotating blower characterized in that a rhythmic wind is generated by the wind of 120).

  According to a second aspect of the present invention, in the first aspect, the diameter of the first impeller (110) is L1, the diameter of the second impeller (120) is L2, and the diameter of the first impeller (110) is When the number of blades is A and the number of blades of the second impeller (120) is B, they are provided so that the relationship of L1 <L2 and A <B is satisfied. It is an inversion fan.

  The present invention has a structure of a counter rotating fan having two impellers on the upstream side and the downstream side, the upstream impeller is driven by a motor, and the downstream impeller receives the upstream wind to rotate. As shown in FIG. 1, as shown in FIG. 1, the air from the upstream impeller deviating from the axial flow direction, that is, the wind that becomes the air loss can be taken in by the rotation of the downstream impeller, and as a result, from the downstream impeller The air blowing efficiency of the air blown in the axial flow direction can be improved.

  In addition, the upstream impeller (first impeller) is turned ON / OFF, and the downstream impeller (second impeller) is reversely operated after this, so as shown in FIG. Unlike perfect ON / OFF, a rhythmic wind with “fluctuation” can be realized.

It is explanatory drawing which shows the rectification | straightening effect by the downstream side impeller (2nd impeller) in this invention. It is explanatory drawing which shows the overlapping ventilation effect by the up-and-down side impeller (1st, 2nd impeller) in this invention. 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 (FIGS. 3 to 8). The counter-rotating blower 1 of this example 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. And a guard 300 surrounding the first impeller 110 and the second impeller 120, and the first impeller 110 and the second impeller 120 rotate in different directions.

  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. 4 has shown the flow of air. 6 indicates the rotation direction of the first impeller 110, and the white arrow in FIG. 7 indicates the rotation direction of the second impeller 120.

  The motor 210 is a DC motor, and uses a DC power source of 5 [V] using USB as a power source. Each impeller 110, 120 is directly connected to a hub 110a linked to a drive shaft of the motor 210 and a hub 120a linked to a shaft not using the motor. The hubs 110a and 120a of the impellers 110 and 120 are set to have the same diameter. In FIG. 5, reference numeral 220 denotes a case. This case 220 uses the motor case of the motor (second motor) of the previous invention (Patent Document 5) in this embodiment. In this example, the case 220 is provided with the second impeller 120. Free rotation is provided. However, the second impeller 120 may be rotatably provided on the hub 120a without using the case 220.

  The motor 210 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 motor 210 is provided at an important point of the support 20 or the base 10. In addition to the ON / OFF function, the switch 30 can adjust the air volume by changing the voltage. The rotation speed in the following description is a value when driving at the maximum voltage.

  In addition to the ON / OFF function, the switch 30 can adjust the air volume by changing the voltage as described above. In this example, as shown in FIG. 3 as an example, an ON / OFF switch position “0”, a maximum voltage drive switch position “1”, and an intermittent drive (rhythmic) switch position “2” are provided. Yes. In the intermittent drive (rhythm wind) of the switch position “2”, as shown in FIG. 2 described above, the amount of change in the air flow is different from complete ON / OFF, and a rhythm wind with “fluctuation” is generated. It can be realized.

  The switch 30 is connected to a control unit (not shown) that controls the rotation speed of the motor 210.

  According to the inventor's knowledge, the counter-rotating blower is superior 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 in terms of the blowing efficiency. Therefore, as a structure for obtaining such air blowing efficiency, the rotational speed decreases as the impeller diameter increases, the rotational speed decreases as the number of blades increases, and the impeller blade width in the axial flow direction. In consideration of the fact that the rotational speed decreases as the air pressure increases, and that the air volume is increased by sucking air from between the first impeller and the second impeller, the diameter L2 of the second impeller is reduced. It is set larger than the diameter L1.

  Further, considering 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 rotation speed of the first impeller becomes relatively larger than the rotation speed of the second impeller.

  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. This is a device for increasing the diameter L2 of the second impeller, and it is possible to inhale air more actively between the first impeller and the second impeller, and the structural balance is achieved. The design has been improved, and the knowledge that the ventilation efficiency is improved has been obtained.

  According to the above configuration, the following structure has been devised in consideration of the point that the blowing efficiency of the counter-rotating blower can be increased.

  In the counter-rotating blower 1 of this example, the diameter of the first impeller 110 is L1, the diameter of the second impeller 120 is L2, the number of blades 111 of the first impeller 110 is A, and the blades 121 of the second impeller 120 are When the number is B, the width of the blade 111 of the first impeller 110 in the axial flow direction is W1, and the width of the blade 121 of the second impeller 120 is W2, they are L1 <L2, A <B, W1> W2. The relationship is established. In the case of this example, the rotation speed of the first impeller 110 is 2400 [rpm].

  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].

Further, when the first impeller 110 and the second impeller 120 are viewed from the front in the axial direction, the distance between the blades 111 with respect to the total impeller area of the first impeller 110 (that is, the total area of the blades 111 constituting the impeller 110) . when the ratio of the gap portion P, and the ratio of the gap portion between each blade 121 with respect to the impeller total area of the second impeller 120 (or blades 121 total area constituting the impeller 120) Q, to, P> Q, It turned out to be preferable.

  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 of the present example, 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. Furthermore, by switching the switch, it is possible to obtain a rhythmic wind with “fluctuation” that is different from the ON / OFF in which the air flow change amount is completely.

  As described above, this example is extremely rationally configured as an open structure counter-rotating blower, and the amount of change in the blow is different from complete ON / OFF, as “fluctuation”. It is possible to realize a certain rhythmic style. 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 fan 10 Base 20 Support body 30 Switch 110 1st impeller 110a Hub 111 Blade 120 2nd impeller 120a Hub 121 Blade 210 Motor 220 Case 300 Guard L1 Diameter of the first impeller L2 Diameter of the second impeller W1 Axial flow Blade width W2 of the first impeller with respect to the direction Width G of the blade of the second impeller with respect to the axial flow direction Distance between the blade of the first impeller and the blade of the second impeller

Claims (2)

A first impeller (110) on the upstream side and a second impeller (120) on the downstream side that are arranged so that the rotation axis centers are aligned in the axial direction, the first impeller (110) and the second impeller (120). Are counter-rotating blowers (1) that rotate in different directions,
The first impeller (110) is rotationally driven by a motor (210),
The second impeller (120) is rotatably provided on the rotating shaft, and is opposite to the rotation direction of the first impeller by the wind force of the first impeller when the first impeller (110) rotates. Non-motor driven , rotating in the direction,
The counter-rotating blower (1) sucks air from the rear in the axial flow direction and sucks air from between the first impeller (110) and the second impeller (120),
Furthermore, when the first impeller (110) and the second impeller (120) are viewed from the front in the axial flow direction, each of the first impeller (110) with respect to the total area of the blade (111) constituting the impeller When the ratio of the gap between the blades is P, and the ratio of the gap between the blades (121) constituting the impeller of the second impeller (120) is Q, the ratio of the gap between the blades is P> Q. Establish relationships so that
The first impeller (110) is intermittently driven by ON / OFF control of the motor (210) to reverse the second impeller (120), and the first impeller (110) and the second impeller ( 120) A counter-rotating blower characterized in that a rhythm wind is generated by the wind of 120).
The diameter of the first impeller (110) is L1, the diameter of the second impeller (120) is L2, the number of blades of the first impeller (110) is A, and the number of blades of the second impeller (120) is 2. The counter-rotating blower according to claim 1, wherein when B, they are provided so that a relationship of L1 <L2 and A <B is satisfied.

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