JP2018115585A - Air blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air blower capable of improving reliability in operation by restricting a pressure difference generated between an upper surface and a lower surface of an air blower.SOLUTION: An air blower 10 of this preferred embodiment comprises; a housing 11 including an inlet port 17a for taking external air, a storing chamber LR communicated with the inlet port and a discharging port 17b for discharging air in the storing chamber to an external part, a motor 12 arranged in the storing chamber of the housing and provided with a coil, and a fan 13 arranged at a rotating shaft of the motor to take external air into the storing chamber from the inlet port and to blow air from the storing chamber into the discharging port. The fan 13 comprises; several plate-like blades 131 arranged on the first surface 13a radially from a rotation center CO toward the peripheral part and several grooves 133 arranged on the second surface 13b opposing against the first surface and at a position opposing between several adjoining blades toward the peripheral part.SELECTED DRAWING: Figure 5B

Description

  Embodiments of the present invention relate to a blower applicable to, for example, a ventilator.

  As a blower for discharging air sucked from an intake port to an exhaust port, for example, there is a blower including an air dynamic pressure bearing in which a rotor and a stator are not in contact with each other during rotation (see, for example, Patent Document 1).

  A blower including an air dynamic pressure bearing has a long life and low sound compared to a blower including a ball bearing type bearing in which a rotor and a stator are in direct contact. Therefore, it is suitable as a blower for ventilators.

Japanese Patent No. 5588747

  However, in a blower equipped with an air dynamic pressure bearing, a pressure difference is generated between the upper surface and the lower surface of the blower fan (blade), and the blower fan moves in a thrust direction from a predetermined position due to the generated pressure difference. There exists a possibility that a ventilation fan may contact the housing which is a case body.

  Therefore, in the embodiment of the present invention, a blower that can improve the reliability by suppressing the pressure difference generated between the upper surface and the lower surface of the blower fan is provided.

  The blower according to the embodiment includes a housing including an intake port that takes in external air, a storage chamber that communicates with the intake port, an exhaust port that discharges air in the storage chamber to the outside, and the storage chamber of the housing A motor provided with a coil, and a fan that is provided on a rotating shaft of the motor, takes in external air from the intake port into the storage chamber, and blows air from the storage chamber to the exhaust port, The fan has a plurality of plate-shaped blades provided radially on the first surface from the center of rotation toward the peripheral portion, and the plurality of blades adjacent on the second surface facing the first surface. And a plurality of grooves provided radially from the center toward the peripheral portion.

The figure which shows the whole structure of the air blower which concerns on 1st Embodiment. The top view which shows the whole structure of the air blower which concerns on 1st Embodiment. Sectional drawing along the III-III line of FIG. Sectional drawing which expands and shows A vicinity shown enclosed with the broken line of FIG. The perspective view which shows the upper surface side of the ventilation fan which concerns on 1st Embodiment. The perspective view which shows the lower surface side of the ventilation fan which concerns on 1st Embodiment. The block diagram which shows the electric constitution of the air blower concerning 1st Embodiment. Sectional drawing for demonstrating the pressure which generate | occur | produces in the case of the ventilation operation | movement of the air blower which concerns on 1st Embodiment. Sectional drawing which shows the flow path which generate | occur | produces in the case of the ventilation operation | movement of the air blower which concerns on 1st Embodiment. Sectional drawing for demonstrating the movement of the ventilation fan in the case of the ventilation operation | movement of the air blower which concerns on 1st Embodiment. Sectional drawing for demonstrating the movement of the ventilation fan in the case of the ventilation operation | movement of the air blower which concerns on a comparative example.

  Hereinafter, embodiments will be described with reference to the drawings. In the following description, substantially the same functions and elements are denoted by the same reference numerals and will be described as necessary. Further, the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like may differ from the actual ones.

(First embodiment)
[Constitution]
overall structure
The whole structure of the air blower concerning 1st Embodiment is demonstrated using FIG. 1, FIG. FIG. 1 is a diagram illustrating an overall configuration of a blower 10 according to the first embodiment. FIG. 2 is a plan view showing the overall configuration of the blower 10 according to the first embodiment.

  As shown in FIGS. 1 and 2, the blower 10 according to the first embodiment includes a housing 11 and a blower fan 13. The blower fan 13 has a plurality of blower blades 131 provided on a rotating shaft of a motor disposed in a housing chamber in the housing 11. The housing 11 has an intake port 17a and an exhaust port 17b, and is constituted by two divided housing members 11a and 11c. The intake port 17a is provided in the upper part of the housing 11, and is comprised from the housing member 11a. The exhaust port 17b is provided in the side part of the housing 11, and is comprised by the housing members 11a and 11b.

Sectional Configuration A sectional configuration of the blower according to the first embodiment will be described in detail with reference to FIGS. 3 and 4. 3 is a cross-sectional view taken along the line III-III in FIG. FIG. 4 is an enlarged cross-sectional view showing the vicinity of A surrounded by a broken line in FIG.

  As shown in FIG. 3, a housing chamber LR for housing the fan unit 51 is provided in the housing 11 so as to communicate with the air inlet 17 a and the air outlet. The fan unit 51 includes a blower fan 13 and a motor 12 for driving the blower fan.

  In the present embodiment, the motor 12 is exemplified by a coreless motor. The motor 12 includes at least a shaft (fixed shaft) 121, a minute gap 122, a sleeve 123, a back yoke 124, a coil 126, a magnet 125, a hub 127, and thrust magnets 128a and 128b. In the above configuration, the shaft 121, the coil 126, and the thrust magnet 128a are stators, and the sleeve 123, the back yoke 124, the magnet 125, the hub 127, and the thrust magnet 128b are rotors.

  The shaft 121 is fixed to the base plate 200 via the pedestal 190. The minute gap 122 is a very small gap provided between the shaft 121 and the sleeve 123. The sleeve 123 is provided on the outer periphery of the shaft 121 through a minute gap 122. The back yoke 124 is provided on the outer periphery of the sleeve 123. The coil 126 is provided on the outer periphery of the back yoke 124. The hub 127 is a rotating member that supports the side surfaces of the sleeve 123 and the magnet 125 and covers the upper portion of the shaft 121. The thrust magnet 128 a is a ring-shaped magnet fixed to the inside of the upper portion of the shaft 121. The thrust magnet 128b is a ring-shaped magnet fixed to the outside of the upper portion of the hub 127 so as to face the thrust magnet 128a. In the present embodiment, an air dynamic pressure bearing is configured by the above configuration.

  Note that another coil as an inductor electrically connected to the coil 126 via the substrate 230 may be provided in the vicinity of the motor 12.

  The blower fan 13 is disposed in the accommodation chamber LR, and is fixed to the hub 127 so that the rotation axis including the center of rotation CO coincides with the rotation axis of the motor 12. On the upper surface of the blower fan 13, a plurality of blower blades 131 are provided for blowing external air taken in from the intake port 17 a to the exhaust port 17 b with a predetermined output (blow pressure and flow rate). The plurality of blower blades 131 are formed of plate-like members provided in the blower fan 13 at predetermined intervals and protruding in the axial direction. Details of the blower fan 13 will be described later.

  Further, in FIG. 4, a predetermined gap (between the upper surface 13 a of the blower fan 13 and the housing member 11 a constituting the housing chamber LR is shown, as enlarged and shown in the vicinity of A of the portion surrounded by the broken line in FIG. 3. A gap (GP1) is provided, and a predetermined gap (gap) GP2 is provided between the lower surface 13b of the blower fan 13 and the housing member 11b constituting the housing chamber LR. By providing these gaps GP1 and GP2, even if the blower fan 13 rotates, a normal blower operation can be performed without the blower fan 13 and the housing 11 contacting each other.

  In addition, the housing member 11a is provided on the base plate 200 arrange | positioned at the bottom part. The base plate 200 and the housing member 11a are fixed by mounting screws 200n that pass through them. Further, the base plate 200 and the substrate 230 are fixed by mounting screws 230n penetrating them.

Detailed Configuration of Blower Fan A detailed configuration of the blower fan 13 included in the blower 10 according to the first embodiment will be described with reference to FIGS. 5A and 5B. FIG. 5A is a perspective view showing the upper surface 13 a side of the blower fan 13. FIG. 5B is a perspective view showing the lower surface 13 b side of the blower fan 13.

  As shown in FIG. 5A, a plurality of blowing blades (blowing blades) 131 are provided on the upper surface 13 a of the blowing fan 13. The plurality of blower blades 131 are configured by plate-like members that are provided at predetermined intervals on the upper surface 13a radially from the central portion including the center of rotation CO toward the peripheral portion and project in the axial direction.

  Further, the plurality of blower blades 131 are configured to bend in a direction (clockwise) opposite to the rotation direction of the blower fan 13 (here, counterclockwise indicated by an arrow in the drawing). With this configuration, air is sucked from the upper intake port 17a, and the air that has been sucked is scrolled to exhaust air from the side exhaust port 17b. Further, by configuring the air blowing blade 131 to be curved, the surface area of the air blowing blade 131 disposed on the upper surface 13a can be increased, and the amount of air entering between the air blowing blades 131 by the rotation of the air blowing fan 13 can be increased.

  As shown in FIG. 5B, convex portions 132 are provided on the lower surface 13b facing the upper surface 13a of the blower fan 13 at positions facing the plurality of blades 131, respectively, so that the radial direction from the center CO toward the peripheral portion is obtained. A plurality of groove portions 133 are provided in the upper surface. In other words, on the lower surface 13 b of the blower fan 13, a plurality of groove portions 133 are provided radially from the center CO toward the peripheral portion at positions facing between the adjacent blades 131. The plurality of convex portions 132 and the plurality of groove portions 133 are provided only in the peripheral portion on the lower surface 13 b of the blower fan 13. There is a cavity OP between the central part including the center CO of the blower fan 13 and the peripheral part, and a plurality of blades 131 are provided on the upper surface 13a across the cavity OP, whereby the central part and the peripheral part of the blower fan 13 are provided. And connected.

  Moreover, the plurality of grooves 133 are configured to curve in a direction opposite to the direction in which the blower fan 13 rotates. In other words, the plurality of grooves 133 are provided curved in the same direction as the plurality of blades 131. By configuring the groove 133 in this way, the air flow path Wb generated along each groove 133 indicated by an arrow in FIG. 5B can be increased during the air blowing operation, and the pressure in the storage chamber LR can be effectively increased. The pressure can be reduced. Details will be described later.

  5B, the height H132 from the lower surface 13b of the convex portion 132 is lower than the height H131 from the upper surface 13a of the blade 133 (H132 <H131). The width W132 of the convex portion 132 is wider than the width W131 of the blade 133 (W132> W131).

Electrical Configuration FIG. 6 schematically shows the configuration of the control system of the blower 10 according to the first embodiment.

  As shown in FIG. 6, the electrical configuration of the control system of the blower 10 includes a fan unit 51 including the motor 12 provided with the blower fan 13 and a drive control unit 52 for controlling the drive of the fan unit 51. Composed. The drive control unit 52 includes a power MOS-FET 32 for switching drive power for driving the motor 12 and a control circuit 31 for controlling the operation of the power MOS-FET 32. The control circuit 31 and the power MOS-FET 32 are mounted on the substrate 230 as predetermined circuit components, for example.

  The power MOS-FET 32 is, for example, a high-voltage power MOS-FET or the like, and one end of a current path (not shown) is electrically connected to a predetermined power source, and the other end is electrically connected to the coil 126 via the substrate 230. And the control terminal is electrically connected to the control circuit 31.

  The control circuit 31 transmits a control signal to the control terminal of the power MOS-FET 32 based on the driving state of the fan unit 51 and controls the power supplied to the motor 12. Therefore, the control circuit 31 may include a controller or the like for controlling the operation of the power MOS-FET 32, for example.

[Blower operation]
The air blowing operation of the blower 10 according to the first embodiment will be described with reference to FIGS. FIG. 7 is a cross-sectional view for explaining the pressure generated during the blowing operation of the blower according to the first embodiment. FIG. 8 is a cross-sectional view showing a flow path generated during the blowing operation of the blower according to the first embodiment.

  In the above configuration, when the motor 12 is driven by the control unit 52, the blower fan 13 rotates, so that the pressure inside the blower 10 becomes a negative pressure compared to the external atmospheric pressure. Outside air is taken into the chamber LR.

  The air taken into the storage chamber LR is scrolled through the storage chamber LR by the blower blade 131 and is exhausted from the exhaust port 17b to the outside with a predetermined output.

  Here, as shown in FIG. 7, when the scroll of the blower blade 131 is continued, the upper surface 13 a side of the blower fan 13 becomes negative pressure and the lower surface 13 b side becomes positive pressure, and the space between the upper surface 13 a and the lower surface 13 b of the blower fan 13. Pressure difference occurs. Due to the generated pressure difference, as indicated by an arrow in the figure, a force is exerted on the blower fan 13 to move to the negative pressure side, which is a low pressure region. Therefore, the blower fan 13 moves from the predetermined position in the axial thrust direction, and the blower fan 13 may abnormally float.

  However, as described above, in the blower 10 according to the present embodiment, the plurality of grooves 133 are provided radially on the lower surface 13b of the blower blade 13 from the center CO toward the peripheral portion. Therefore, as shown in FIG. 5B, when the blower fan 13 rotates, air collides with the convex portion 132 and air is collected in each groove portion 133, and an air flow path Wb is generated along each groove portion 133. .

  Therefore, as shown in FIG. 8, the air in the housing chamber LR of the housing 11 is sucked out from the exhaust port 17b to the outside by the air flow path Wb. More specifically, it is accommodated between the housing 11a on the side surface of the motor 12 and the hub 127 along with the air flow path Wb generated in the gap (gap GP2) between the lower surface 13b of the blower fan 13 and the housing 11a. An air flow path Wb1 is generated so as to suck out the air in the chamber LR. Due to the generated flow paths Wb and Wb1, the positive pressure generated in the gap GP2 on the lower surface 13b side is reduced, the pressure difference between the upper surface 13a and the lower surface 13b of the blower fan 13 is suppressed, and in the thrust direction of the blower fan 13 Can be prevented.

[Function and effect]
Here, as shown in FIG. 9, in the blower 100 according to the comparative example, when the scroll of the blower blade is continued, as described above, the upper surface side of the blower fan has a negative pressure and the lower surface side has a positive pressure. A pressure difference is generated between the upper surface and the lower surface. The cause of this pressure difference is that the upper surface of the blower fan communicates with the intake port and is open to the atmosphere, so the pressure becomes atmospheric pressure, but the pressure on the lower surface of the blower fan is equivalent to the internal pressure in the housing. It depends. However, the blower 100 according to the comparative example does not include the configuration of the groove 133 according to the present embodiment. For this reason, the generated pressure difference gradually increases, and the force to float on the negative pressure side acting on the blower fan also increases. Therefore, the gap GP12 between the lower surface of the blower fan and the housing increases, and the blower fan moves in the thrust direction until the gap GP11 between the upper surface and the housing becomes substantially zero, and the blower fan comes into contact with the housing. There is a fear. Moreover, if the lower surface side of the blower fan is opened to the atmosphere and the pressure is set to atmospheric pressure, the blower efficiency is reduced.

  Therefore, the blower 10 according to the first embodiment includes a plurality of grooves 133 provided radially on the lower surface 13b of the blower blade 13 from the center CO toward the periphery. In the above configuration, when the blower fan 13 rotates, air is collected in each groove 133, and an air flow path Wb from the center CO toward the periphery is generated in each groove 133 (FIG. 5B). By the air flow path Wb, the air in the housing chamber LR of the housing 11 is sucked out from the exhaust port 17b by the scroll of the blower blade 131 (FIG. 8).

  As a result, as shown in FIG. 10, the positive pressure generated in the gap GP2 on the lower surface 13b side of the blower fan 13 is reduced and generated in the gap GP1 on the upper surface 13a side and the gap GP2 on the lower surface 13b side of the blower fan 13. Pressure can be equalized. As a result, the gap GP1 on the upper surface 13a side and the gap GP2 on the lower surface 13b side of the blower fan 13 can be maintained regardless of before and after the blower operation, and the movement of the blower fan 13 in the thrust direction can be prevented. This is advantageous in that the property can be improved. Furthermore, in this embodiment, since the pressure on the lower surface 13b side of the blower fan 13 is connected to the upper surface 13a side without releasing to the atmosphere, the drive efficiency of the motor 12 with respect to the supplied power can be prevented from being lowered, and the output of the blower 10 can be reduced. There is no decline.

  Moreover, since the flow rate of the air flow path Wb generated in the groove 133 is configured to increase according to the rotational speed of the blower fan 13, the air flow in the thrust direction according to the rotational speed of the blower fan 13. The displacement amount of the fan 13 can be effectively suppressed.

  Furthermore, since the blower blade 131, the convex part 132, and the groove part 133 are integrally formed of a predetermined resin or the like, a desired shape can be formed precisely and easily.

  Moreover, the displacement amount to the thrust direction of the ventilation fan 13 is controllable by selecting the number of the groove part 133, depth (height H132 of the convex part 132), and width | variety (width W132 of a convex part).

  Further, in the present embodiment, the plurality of convex portions 132 and the plurality of groove portions 133 are provided only in the peripheral portion of the lower surface 13b of the blower fan 13, and between the central portion including the center CO of the blower fan 13 and the peripheral portion. Has a cavity OP, and a plurality of blades 131 are provided across the cavity OP on the upper surface 13a, thereby connecting the central portion and the peripheral portion of the blower fan 13. Therefore, the blower fan 13 can be reduced in weight, and power consumption can be reduced.

  In addition, when the blower 10 according to the present embodiment is used as a ventilator for a ventilator or the like, unlike a general blower, it is not necessary to frequently turn on / off the blowing operation, but it is longer and stable. A blowing operation is required. Therefore, when the blower 10 according to the present embodiment is applied as a blower for the artificial respirator, a pressure difference between the upper surface 13a and the lower surface 13b of the blower fan can be suppressed, so that reliable blowing operation is performed stably. It becomes possible.

  In the case where the control circuit 31 and the power MOS-FET 32 that serve as heating elements during the blowing operation are arranged on the substrate 230, these heating elements can be cooled by the air flow paths Wb and Wb1. Therefore, the temperature rise of the coil 126 of the motor 12 due to the heat generated from the control circuit 31 and the power MOS-FET 32 can be suppressed, and the output of the blower 10 can be prevented from being lowered.

(Modification)
The embodiment of the present invention is not limited to the contents disclosed in the first embodiment, and it is needless to say that various modifications are possible as necessary.

  For example, in the blower 10 according to the first embodiment, the number of the groove portions 133 is the same as the number of the blower blades 131, but is not limited thereto. Further, the depth (height H132 of the convex portion 132) and the width (width W132 of the convex portion) of the groove portion 133 can be selected as necessary.

  Furthermore, in the shape of the groove part 133, the structure in which the side surface is substantially perpendicular to the horizontal plane is given as an example, but the present invention is not limited to this. For example, the side surface of the groove part 133 has a predetermined taper angle with respect to the horizontal plane. It may be configured.

  In addition, the use of the air blower 10 disclosed in the present embodiment is not limited to a ventilator. Needless to say, the present invention is widely applicable to other air blowing applications such as medical use for continuous positive airway pressure (CPAP) for the treatment of sleep apnea syndrome.

  In addition, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 10 ... Blower, 11 ... Housing, 11a, 11b ... Housing member, 12 ... Motor, 13 ... Blower fan, 13a ... Blower fan upper surface, 13b ... Blower fan lower surface, 17a ... Intake port, 17b ... Exhaust port, 31 ... Control circuit, 32... Power MOS-FET, 131... Blower blade, 132 .. Projection, 133 .. Groove, LR .. Storage chamber, Wb, Wb1.

Claims (5)

A housing comprising an intake port for taking in external air, a storage chamber communicating with the intake port, and an exhaust port for discharging the air in the storage chamber to the outside;
A motor provided in the housing chamber of the housing and provided with a coil;
A fan that is provided on the rotating shaft of the motor, takes in external air from the intake port into the storage chamber, and blows air from the storage chamber to the exhaust port;
The fan has a plurality of plate-shaped blades provided radially on the first surface from the center of rotation toward the peripheral portion, and the plurality of blades adjacent on the second surface facing the first surface. A plurality of grooves provided radially from the center toward the peripheral portion at positions facing each other. The blower according to claim 1, wherein the plurality of grooves are provided only in a peripheral portion on the second surface of the fan. The blower according to claim 1, wherein the number of the plurality of grooves is the same as the number of the plurality of blades. The plurality of blades are provided curved in a direction opposite to a direction in which the fan rotates,
The blower according to any one of claims 1 to 3, wherein the plurality of grooves are curved in the same direction as the plurality of blades. A cavity is provided between a central part including the center of the fan and the peripheral part,
The blower according to any one of claims 1 to 4, wherein the plurality of blades are provided on an upper surface of the fan across the cavity to connect a central portion and a peripheral portion of the fan.

Images