CN108194387B - Axial flow fan - Google Patents

Axial flow fan Download PDF

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Publication number
CN108194387B
CN108194387B CN201810183990.5A CN201810183990A CN108194387B CN 108194387 B CN108194387 B CN 108194387B CN 201810183990 A CN201810183990 A CN 201810183990A CN 108194387 B CN108194387 B CN 108194387B
Authority
CN
China
Prior art keywords
outer rotor
blade
hub
impeller
rotor motor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810183990.5A
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Chinese (zh)
Other versions
CN108194387A (en
Inventor
王书勤
李华
杨坚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Changzhou Xiangming Intelligent Power Co ltd
Original Assignee
Changzhou Xiangming Intelligent Power Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Changzhou Xiangming Intelligent Power Co ltd filed Critical Changzhou Xiangming Intelligent Power Co ltd
Priority to CN201810183990.5A priority Critical patent/CN108194387B/en
Publication of CN108194387A publication Critical patent/CN108194387A/en
Application granted granted Critical
Publication of CN108194387B publication Critical patent/CN108194387B/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D19/00—Axial-flow pumps
    • F04D19/002—Axial flow fans
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D25/00—Pumping installations or systems
    • F04D25/02—Units comprising pumps and their driving means
    • F04D25/08—Units comprising pumps and their driving means the working fluid being air, e.g. for ventilation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/263—Rotors specially for elastic fluids mounting fan or blower rotors on shafts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/325—Rotors specially for elastic fluids for axial flow pumps for axial flow fans
    • F04D29/329—Details of the hub
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/38—Blades
    • F04D29/388—Blades characterised by construction
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/58—Cooling; Heating; Diminishing heat transfer
    • F04D29/582—Cooling; Heating; Diminishing heat transfer specially adapted for elastic fluid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/60—Mounting; Assembling; Disassembling
    • F04D29/64—Mounting; Assembling; Disassembling of axial pumps
    • F04D29/644—Mounting; Assembling; Disassembling of axial pumps especially adapted for elastic fluid pumps
    • F04D29/646—Mounting or removal of fans
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
    • F04D29/667—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by influencing the flow pattern, e.g. suppression of turbulence
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/70—Suction grids; Strainers; Dust separation; Cleaning
    • F04D29/701—Suction grids; Strainers; Dust separation; Cleaning especially adapted for elastic fluid pumps
    • F04D29/703—Suction grids; Strainers; Dust separation; Cleaning especially adapted for elastic fluid pumps specially for fans, e.g. fan guards

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

The invention relates to an axial flow fan, which is provided with an outer rotor motor, a fixing frame and an impeller; the fixing frame is provided with an outer ring body; the outer rotor motor is fixedly connected to the center of the fixing frame; the impeller is fixedly connected to an outer rotor of the outer rotor motor; the impeller is rotatably arranged in the outer ring body; the impeller comprises a hub; a plurality of blades are circumferentially distributed on the hub along the rotation axis; the center of the hub is provided with a through hole for the outer rotor of the outer rotor motor to pass through, and fixing holes are distributed on the hub around the circumference of the through hole; an annular flange connection disc is arranged on the circumferential surface of the outer rotor motor; the hub is sleeved outside the outer rotor of the outer rotor motor and fixedly connected with the annular flange connecting disc through a connecting bolt penetrating through the fixing hole. The invention greatly reduces the overall height by connecting the impeller and the outer rotor motor, and is also applicable to some limited installation spaces.

Description

Axial flow fan
Technical Field
The present invention relates to an axial flow fan.
Background
An axial flow fan is a device that rotates an impeller to flow gas parallel to the axial flow of the fan. Axial fans are commonly used in applications where flow requirements are high and pressure requirements are low. The axial flow fan has very wide application, such as electric fan, air conditioner fan, automobile axial flow fan, etc. The axial flow fan mainly comprises an impeller and a shell, has a simple structure and has very high index requirements.
When the impeller of the traditional axial flow fan is fixedly connected with the outer rotor motor, the hub of the impeller is sleeved on the outer rotor of the outer rotor motor, and then the impeller is fixedly connected with the outer rotor motor through bolts. Since the hub of the impeller itself has a certain thickness, the overall height increases after installation, and is not suitable for use in some special environments.
Meanwhile, as a core component impeller of the axial flow fan, the impeller has good aerodynamic performance and noise index, which are key to determining the performance of the axial flow fan. The pneumatic performance and noise of the impeller can be directly influenced by the arrangement of the blades on the impeller, the shapes of the blades, the angles of the blades and other designs.
In addition, in order to ensure the performance of some impellers for axial flow fans, a rotating ring is added to the top of the blades. The connection between the top of the blade and the rotating ring often forms a great amount of dust deposit with use, thereby affecting the performance of the axial flow fan. To solve the above problems, it is often necessary to remove the accumulated ash by maintenance. However, due to the existence of the dust deposition problem, the maintenance frequency of the axial flow fan is excessive, and the use efficiency is reduced.
Disclosure of Invention
The invention aims to provide an axial flow fan which has low height, good overall aerodynamic performance and low noise and can effectively reduce maintenance frequency.
The technical scheme for realizing the aim of the invention is as follows: the invention has an outer rotor motor, a fixing frame and an impeller; the fixing frame is provided with an outer ring body; the outer rotor motor is fixedly connected to the center of the fixing frame; the impeller is fixedly connected to an outer rotor of the outer rotor motor; the impeller is rotatably arranged in the outer ring body; the impeller comprises a hub; a plurality of blades are circumferentially distributed on the hub along the rotation axis; the center of the hub is provided with a through hole for the outer rotor of the outer rotor motor to pass through, and fixing holes are distributed on the hub around the circumference of the through hole; an annular flange connection disc is arranged on the circumferential surface of the outer rotor motor; the hub is sleeved outside the outer rotor of the outer rotor motor and fixedly connected with the annular flange connecting disc through a connecting bolt penetrating through the fixing hole.
The inner side surface of the through hole of the hub is provided with a plurality of reinforcing ribs which are circumferentially distributed along the rotation axis and are parallel to the rotation axis.
One side of the blade is a front edge, and the other side is a rear edge; the front edge of the blade is provided with a turbulator integrated with the blade; the turbulator comprises a plurality of protrusions arranged along the extension direction of the leading edge; the arrangement of the protrusions forms a wave shape.
Simultaneously, the rotating ring is coaxial with the hub; the hub is connected with the root of the blade into a whole, and the top of the blade is connected with the rotating ring into a whole.
The turbulators extend from the blade root to the blade tip; the protrusion of the turbulator at the root of the blade is connected with the hub into a whole; the protrusions of the turbulators at the top of the vanes are integrally connected with the rotating ring.
The turbulators are arranged on the protrusions at the top of the blade, naturally transition to the direction away from the front edge of the blade and gradually approaching the rotating ring, and form an extension part which is connected with the rotating ring into a whole and is higher than other protrusions.
The bulge comprises a rising part and a falling part; the turbulators are arranged on the protrusions at the tops of the blades, and naturally transition to the rotating ring along the extending direction of the rising parts of the turbulators to form extending parts which are connected with the rotating ring into a whole and are higher than other protrusions.
The included angle between the tangent line of the blade top and the tangent line of the rotating ring is 10-30 degrees.
A notch is arranged at the intersection of the rotating ring and the pressure surface of the blade; the bottom surface of the notch extends along the pressure surface of the corresponding blade.
Preferably, the bottom surface of the notch extends from an end of the extension remote from the leading edge of the blade to the trailing edge of the blade.
The invention has the positive effects that: (1) The invention greatly reduces the overall height by adopting the connection mode of the impeller and the outer rotor motor, so that the invention is also applicable to environments with effective installation space;
(2) The invention greatly improves the overall aerodynamic performance by the turbulator, and can reduce noise;
(3) According to the invention, through the optimized design of the turbulator, the aerodynamic performance is further improved, and the noise is further reduced;
(4) According to the invention, through the extension part of the turbulator, the aerodynamic performance is further improved, and the noise is further reduced;
(5) According to the invention, through the notch on the rotating ring, the dust collection dead angle is eliminated, and the maintenance frequency of the fan is greatly reduced;
(6) The optimal design of the notch further eliminates the ash deposition dead angle;
(7) According to the invention, the radiating effect can be effectively increased through the ribs, and the stability and the service life of long-time work are ensured.
Drawings
In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings, in which
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is an exploded view of the present invention;
FIG. 3 is a schematic view of the structure of the outer rotor motor according to the present invention;
FIG. 4 is a schematic view of the impeller of the present invention;
FIG. 5 is a front view of an impeller of the present invention;
FIG. 6 is a graph of air volume versus air pressure test versus an impeller of the present invention;
FIG. 7 is a graph of air volume versus efficiency test versus an impeller of the present invention;
FIG. 8 is a graph of air volume versus noise test versus an impeller of the present invention.
Detailed Description
Example one
Referring to fig. 1 to 5, the invention has an outer rotor motor 1, a fixed frame 2 and an impeller 3; the fixing frame 2 is provided with an outer ring body; the outer rotor motor 1 is fixedly connected to the center of the fixing frame 2; the impeller 3 is fixedly connected to the outer rotor of the outer rotor motor 1; the impeller 3 is rotatably arranged in the outer ring body; the impeller 3 comprises a hub 31 and a rotating ring 33 coaxially arranged; a plurality of blades 32 are circumferentially distributed between the hub 31 and the rotating ring 33 along the rotation axis; hub 31 is integrally connected to blade root portion 322, and blade tip portion 323 is integrally connected to rotating ring 33.
The center of the hub 31 is provided with a through hole for the outer rotor of the outer rotor motor 1 to pass through, and the hub 31 is provided with fixing holes around the circumference of the through hole; an annular flange connection disc is arranged on the circumferential surface of the outer rotor motor 1; the hub 31 is sleeved outside the outer rotor of the outer rotor motor 1 and fixedly connected with the annular flange connection disc through a fixing hole by a connecting bolt.
The inner side surface of the through hole of the hub 31 is provided with a plurality of reinforcing ribs 311 circumferentially distributed along the rotation axis and parallel to the rotation axis.
One side of the blade 32 is the leading edge and the other side is the trailing edge; the front edge of the blade 32 is provided with a turbulator 321 which is integrated with the blade 32; the turbulator 321 includes a plurality of protrusions aligned along the extension of the leading edge; the arrangement of the protrusions forms a wave shape.
The turbulators 321 extend from the blade root 322 to the blade tip 323; the protrusions of the turbulators 321 at the blade root 322 are integrally connected with the hub 31; the turbulator sites 321 are integrally connected to the rotating ring 33 by protrusions at the blade tips 323.
The bulge comprises a rising part and a falling part; the turbulators 321 are located at the projections of the blade tips 323, and naturally transition to the rotating ring 33 along the extending direction of the rising parts thereof to form extending parts 324 which are connected with the rotating ring 33 into a whole and are higher than other projections.
The angle between the tangent of the blade tip 323 and the tangent of the rotating ring 33 is 10 DEG to 30 deg.
A notch 34 is arranged at the intersection of the rotating ring 33 and the pressure surface 325 of the blade 32; the bottom surface of the notch 34 extends along the pressure surface 325 of its corresponding vane 32. And from an end of the extension 324 remote from the leading edge of the blade 32 to the trailing edge of the blade 32.
The inner wall of the hub 31 is circumferentially provided with ribs for dissipating heat during rotation along the rotation axis.
The ribs are in a blade shape.
As shown in fig. 6 to 8, the present invention has more outstanding aerodynamic performance and low noise.
Example two
The turbulators 321 of the present invention are located at the protrusions of the blade tip 323, naturally transition to a direction away from the front edge of the blade 32 and gradually approaching the rotating ring 33, and form an extension 324 integrally connected with the rotating ring 33 and higher than the other protrusions. Other technical features are the same as those of the first embodiment.
While the foregoing is directed to embodiments of the present invention, other and further details of the invention may be had by the present invention, it should be understood that the foregoing description is merely illustrative of the present invention and that no limitations are intended to the scope of the invention, except insofar as modifications, equivalents, improvements or modifications are within the spirit and principles of the invention.

Claims (2)

1. An axial flow fan is provided with an outer rotor motor (1), a fixing frame (2) and an impeller (3); the fixing frame (2) is provided with an outer ring body; the outer rotor motor (1) is fixedly connected to the center of the fixing frame (2); the impeller (3) is fixedly connected to the outer rotor of the outer rotor motor (1); the impeller (3) is rotatably arranged in the outer ring body; the method is characterized in that: the impeller (3) comprises a hub (31); a plurality of blades (32) are circumferentially distributed on the hub (31) along the rotation axis; the center of the hub (31) is provided with a through hole for the outer rotor of the outer rotor motor (1) to pass through, and the hub (31) is provided with fixing holes around the circumference of the through hole; an annular flange connection disc is arranged on the circumferential surface of the outer rotor motor (1); the hub (31) is sleeved outside the outer rotor of the outer rotor motor (1) and fixedly connected with the annular flange connecting disc through a connecting bolt penetrating through a fixing hole;
The inner side surface of the through hole of the hub (31) is provided with a plurality of reinforcing ribs (311) which are circumferentially distributed along the rotation axis and are parallel to the rotation axis; one side of the blade (32) is a front edge, and the other side is a rear edge; the front edge of the blade (32) is provided with a turbulator (321) which is integrated with the blade (32); the turbulator (321) comprises a plurality of protrusions arranged along the extension direction of the leading edge; the arrangement of the bulges forms a wave shape; a rotating ring (33) coaxial with the hub (31); the hub (31) is connected with the blade root (322) into a whole, and the blade top (323) is connected with the rotating ring (33) into a whole; the turbulators (321) extend from the blade root (322) to the blade tip (323); the protrusion of the turbulator (321) positioned at the root (322) of the blade is connected with the hub (31) into a whole; the protrusion of the turbulator (321) positioned at the blade top (323) is connected with the rotating ring (33) into a whole;
the bulge comprises a rising part and a falling part; the turbulators (321) are arranged on the protrusions of the blade tops (323), naturally transition to the rotating ring (33) along the extending direction of the rising parts of the turbulators to form extending parts (324) which are connected with the rotating ring (33) into a whole and are higher than other protrusions;
A notch (34) is arranged at the intersection of the rotating ring (33) and the pressure surface (325) of the blade (32); the bottom surface of the notch (34) extends along the pressure surface (325) of the corresponding blade (32);
The bottom surface of the notch (34) extends from an end of the extension (324) remote from the leading edge of the blade (32) to the trailing edge of the blade (32).
2. The axial flow fan according to claim 1, wherein: the included angle between the tangent line of the blade top (323) and the tangent line of the rotating ring (33) is 10-30 degrees.
CN201810183990.5A 2018-03-07 2018-03-07 Axial flow fan Active CN108194387B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810183990.5A CN108194387B (en) 2018-03-07 2018-03-07 Axial flow fan

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810183990.5A CN108194387B (en) 2018-03-07 2018-03-07 Axial flow fan

Publications (2)

Publication Number Publication Date
CN108194387A CN108194387A (en) 2018-06-22
CN108194387B true CN108194387B (en) 2024-06-14

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CN201810183990.5A Active CN108194387B (en) 2018-03-07 2018-03-07 Axial flow fan

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Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109209952A (en) * 2018-11-09 2019-01-15 仪坤动力科技（上海）有限公司 Blade and internal rotor integral structure and blower with fixing axle

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000087898A (en) * 1998-09-08 2000-03-28 Matsushita Refrig Co Ltd Axial flow blower
CN202391808U (en) * 2011-12-13 2012-08-22 广东美的电器股份有限公司 Low-noise axial flow air wheel
CN103062111A (en) * 2012-10-09 2013-04-24 宁波风机有限公司 Fan impeller
CN103671250A (en) * 2012-09-05 2014-03-26 德昌电机(深圳)有限公司 Fan
CN204003532U (en) * 2014-07-21 2014-12-10 王东茂 Removable fan structure
JP2016102467A (en) * 2014-11-28 2016-06-02 株式会社デンソー Blower device
CN207906107U (en) * 2018-03-07 2018-09-25 常州祥明智能动力股份有限公司 Axial flow blower

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Publication number Priority date Publication date Assignee Title
US8152484B2 (en) * 2009-04-09 2012-04-10 Robert Bosch Gmbh Engine cooling fan assembly
IT1404254B1 (en) * 2011-01-25 2013-11-15 Gate Srl FAN, PARTICULARLY FOR A VENTILATION GROUP FOR A HEAT EXCHANGER OF A MOTOR VEHICLE
CN104196754B (en) * 2014-08-11 2017-06-20 上海马陆日用友捷汽车电气有限公司 Multifunctional fan blade wheel hub
CN206397810U (en) * 2016-12-27 2017-08-11 广东泛仕达机电有限公司 A kind of impeller assembly and the blower fan including the impeller assembly

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000087898A (en) * 1998-09-08 2000-03-28 Matsushita Refrig Co Ltd Axial flow blower
CN202391808U (en) * 2011-12-13 2012-08-22 广东美的电器股份有限公司 Low-noise axial flow air wheel
CN103671250A (en) * 2012-09-05 2014-03-26 德昌电机(深圳)有限公司 Fan
CN103062111A (en) * 2012-10-09 2013-04-24 宁波风机有限公司 Fan impeller
CN204003532U (en) * 2014-07-21 2014-12-10 王东茂 Removable fan structure
JP2016102467A (en) * 2014-11-28 2016-06-02 株式会社デンソー Blower device
CN207906107U (en) * 2018-03-07 2018-09-25 常州祥明智能动力股份有限公司 Axial flow blower

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