GB2478646A - Fan blade spacing and/or construction - Google Patents

Fan blade spacing and/or construction Download PDF

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Publication number
GB2478646A
GB2478646A GB1103949A GB201103949A GB2478646A GB 2478646 A GB2478646 A GB 2478646A GB 1103949 A GB1103949 A GB 1103949A GB 201103949 A GB201103949 A GB 201103949A GB 2478646 A GB2478646 A GB 2478646A
Authority
GB
United Kingdom
Prior art keywords
fan
hand
machine tool
held machine
blades
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.)
Withdrawn
Application number
GB1103949A
Other versions
GB201103949D0 (en
Inventor
Marco Zucchini
Robert Simm
Pasquale Oliverio
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of GB201103949D0 publication Critical patent/GB201103949D0/en
Publication of GB2478646A publication Critical patent/GB2478646A/en
Withdrawn legal-status Critical Current

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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
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
    • F04D29/281—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps for fans or blowers
    • 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
    • F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
    • F04D29/30—Vanes
    • 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
    • F04D29/666—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by means of rotor construction or layout, e.g. unequal distribution of blades or vanes

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

Abstract

A hand-held machine tool fan has at least three fan blades 12 which have at least partly identical effective regions 14 in use. The blades are arranged at irregular distances 16, 18 from one another, and/or have effective surfaces 20 of differing construction. The intake and/or output edges 22, 24 may be of differing construction. At least two blades may be arranged in pairs. The blades may move air in the peripheral direction 26 of the fan axis 28. A fan hub 30 may deflect the airflow 32 by more than 45 degrees. A centre of gravity of the blades may be close to the fan axis. A stabilising ring 34 may be provided at least in the peripheral direction of the fan axis.

Description

Description
Hand-held machine tool fan
Prior art
The starting point of the invention is a hand-held machine tool fan in accordance with the pre-characterising clause of claim 1.
A hand-held machine tool fan with at least three fan blades which have an at least partly identical effective region during operation has already been proposed. In this instance, the fan blades are arranged at regular distances from one another and have effective surfaces of identical shape.
Disclosure of the invention
The starting point of the invention is a hand-held machine tool fan with at least three fan blades which have an at least partly identical effective region during operation.
It is proposed that the fan blades are arranged at irregular distances from one another and/or have effective surfaces of differing construction. A "fan blade" should be understood to mean, in particular, an element which is intended to move, by means of the effective surface, at least air which is arranged within the effective region.
The fan blades are preferably mounted so as to be capable of rotating movement about a fan axis. Said fan blades advantageously have a main extension surface which is oriented substantially parallel to a radial direction of the fan axis and, particularly advantageously, substantially perpendicular to a peripheral direction of said fan axis. In this connection, "substantially parallel or perpendicular" should be understood to mean with an angle of less than 60 degrees, advantageously less than 30 degrees and, particularly advantageously, less than 10 degrees, between the main extension surface and the radial direction or between the peripheral direction and a normal of said main extension surface, respectively. A main extension surface might, in particular, be constructed so as to be curved, advantageously by less than 30 degrees.
"Intended" should be understood to mean, in particular, specially equipped and/or designed. "Have an at least partly identical effective region" should be understood to mean, in particular, that bodies of revolution of the fan blades encompass, at least in part, an identical space around the fan axis. An "effective surface" should be understood to mean, in particular, a surface of the fan blade which is intended to transmit energy to an airflow in the effective region when the fan blade rotates about the fan axis. The effective surface of the fan blade is preferably oriented parallel to the main extension surface of the same fan blade. The phrase "at irregular distances from one another" should be understood to mean, in particular, that a distance in the peripheral direction on a radius around the fan axis between at least a first fan blade and an adjacent second fan blade and a distance in the peripheral direction on the radius between the second fan blade and an adjacent third fan blade are different in size. The fan blades are preferably arranged so as to be distributed asymmetrically around the fan axis. In this connection, "asymmetrically" should be understood to mean that connections of points which lie on the effective surface and which are arranged on a specific radius around the fan axis only form irregular polygons. In particular, "effective surfaces of differing construction" should be understood to mean effective surfaces which differ in distance relative to the fan axis, in size and/or, advantageously, in shape. By configuring the hand-held machine tool fan in accordance with the invention, particularly quiet and, at the same time, efficient operation can be achieved. In particular, it is possible to avoid unwanted sounds within an audible frequency range, and to do so at different and, in particular, low rotational speeds. In addition, a particularly quiet fan with few fan blades and thereby a high capacity can be obtained.
In another configuration, it is proposed that the fan blades have intake edges of differing construction, as a result of which particularly low intake noise during operation is possible. An "intake edge" should be understood to mean, in particular, an edge of the fan blade which, in a body of revolution of the fan blade around the fan axis, forms a surface through which air flows into the effective region of the fan blade during operation. In particular, "edges of differing construction" should be understood to mean edges which differ in shape and/or, advantageously, at least in distance relative to the fan axis.
Furthermore, it is proposed that the fan blades have output edges of differing construction, as a result of which it is possible to achieve particularly low fan noise on the output side during operation. An "output edge" should be understood to mean, in particular, an edge of the fan blade which forms, in the case of a body of revolution of the fan blade around the fan axis, a surface through which air flows out of the effective region of the fan blade during operation.
It is further proposed that at least two fan blades are arranged in pairs, as a result of which it is possible to obtain, in a simple manner in terms of design, a fan which is quiet during operation. "Arranged in pairs" should be understood to mean, in particular, that at least two mutually adjacent fan blades belonging to a section are arranged so as to be spaced apart from one another on a radius which amounts to a maximum of 75%, and advantageously a maximum of 50%, of a section between one of the fan blades which are arranged in pairs and a third fan blade.
In addition, it is proposed that the fan blades are intended to move air substantially in the peripheral direction of the fan axis, as a result of which it is possible to make available a hand-held machine tool fan which has a high capacity and can be integrated into a housing in a simple manner in terms of design. In a preferred manner, the fan blades preferably move the air outwards on a circular path, in particular a spiral path.
In this connection, "outwards" should be understood to mean, in particular, in a direction that points away from the fan axis.
It is furthermore proposed that the hand-held machine tool fan has a fan hub which is intended to deflect a direction of airflow by more than 45 degrees. A "fan hub" should be understood to mean, in particular, an element which connects the fan blades to a unit that drives them. The term "direction of airflow" should be understood to mean, in particular, a direction in which the air flows, on average, at a point during operation. As a result of the fan hub according to the invention, an airflow that extends in an advantageous manner can be achieved.
In one advantageous construction of the invention, it is proposed that a centre of gravity of the fan blades is arranged close to a fan axis, as a result of which particularly high smoothness of running and low wear can be achieved. In this connection, "close to" should be understood to mean arranged at a distance of less than mm, and advantageously less than 2 mm.
Furthermore, it is proposed that the hand-held machine tool fan has a stabilising ring which fastens the fan blades at least in the peripheral direction of the fan axis, as a result of which particularly thin fan blades are possible.
A "stabilising ring" should be understood to mean, in particular, an annular element which is intended to bring about a force on the fan blades in the peripheral direction.
The starting point of the invention is also a hand-held machine tool with a hand-held machine tool fan, wherein all the hand-held machine tools that seem appropriate to the person skilled in the art, such as, in particular, drilling machines, drill and chisel hammers, saws, planes, screwdrivers, milling cutters, grinders, angle grinders and/or multifunction tools, would be conceivably possible for operation with a hand-held machine tool fan, as a result of which a particularly quiet and effectively ventilated hand-held machine tool can be made available.
Drawings Further advantages emerge from the following description of the drawings. An exemplified embodiment of the invention is represented in the drawings. Said drawings, the description and the claims contain numerous features in combination. The person skilled in the art will also consider the features individually in a suitable manner, and put them together to form appropriate further combinations.
Fig. 1 shows a hand-held machine tool fan according to the invention, in a perspective view, and Fig. 2 shows a partial section through a hand-held machine tool with the hand-held machine tool fan according to figure 1.
Description of the exemplified embodiment
Figure 1 shows a hand-held machine tool fan 10 according to the invention with twenty-one fan blades 12, a fan hub 30 and a stabilising ring 34. Said hand-held machine tool fan is constructed as a radial fan. As figure 2 shows, the hand-held machine tool fan 10 can be connected to a fan shaft 38 in a torque-proof manner. Said hand-held machine tool fan 10 can be driven, by means of the fan shaft 38, in a manner rotating about a fan axis 28.
A main extension surface of each fan blade 12 is oriented perpendicularly to a peripheral direction 26 of the fan axis 28. The hand-held machine tool fan 10 is thus constructed as a radial fan. The fan blades 12 are all arranged, in part, on identical radii around the fan axis 28. They consequently have, during operation, a partly identical effective region 14. During operation, the fan blades 12 move air substantially in the peripheral direction 26 of the fan axis 28, namely on a spiral path away from said fan axis 28.
The fan blades 12 are arranged at irregular distances 16, 18 from one another. The distance 16 between a first fan blade 12' and an adjacent second fan blade 12" and the distance 18 between the second fan blade 12" and a third fan blade 12E differ from one another, and do so by more than 10%.
The fan blades 12 have effective surfaces 20 of differing construction. Figure 2 shows a partial section through the hand-held machine tool fan 10 and through the effective region 14 between two fan blades 12. Only one fan blade 12 is represented in the background. Possible effective surfaces 20 of differing construction are shown on the fan blade 12 which is represented. Other shapes and/or sizes of effective surface that seem appropriate to the person skilled in the art are possible.
The fan blades 12 have intake edges 22 of differing construction and output edges 24 of differing construction.
The intake edges 22 extend from the fan hub 30 in an arc-shaped manner in a direction pointing away from the fan axis 28. The fan hub 30 and a surface of revolution which is formed by one of the intake edges 22 around the fan axis 28 enclose an intake region 40 through which air flows into the effective region 14. The air flows into the intake region 40 in a manner substantially parallel to the fan axis 28. During operation, the fan hub 30 thus deflects a direction of airflow 32 by more than 45 degrees on a plane which is oriented parallel to the fan axis 28. The output edges 24 are formed by edges of the fan blades 12 which are arranged in a manner facing away from the fan axis 28.
Possible intake edges 22 and possible output edges 24 are represented in figure 2. Other shapes of intake edges and output edges that seem appropriate to the person skilled in the art are possible.
At least two of the fan blades 12', 12" are arranged in pairs. The distance between these fan blades 12', 12" is about half as great as a minimum distance between one of the fan blades 12', 12" arranged in pairs and another fan blade 12, 12L1.
The stabilising ring 34 of the hand-held machine tool fan is constructed as an annular surface. It surrounds the fan axis 28 coaxially and is oriented perpendicularly to said fan axis 28. The stabilising ring 34 connects the fan blades 12 to one another. Said stabilising ring 34 thus fastens the fan blades 12 in the peripheral direction 26 of the fan axis 28. The centres of gravity of all the fan blades 12, of the fan hub 30 and of the stabilising ring 34 are arranged on the fan axis 28 in each case.
Alternatively, it might be possible to arrange only one common centre of gravity of fan blades, of a fan hub and of a stabilising ring on a fan axis. In that case, for example, a centre of gravity of fan blades and a centre of gravity of a stabilising ring would balance each other out.
As figure 2 shows, the effective region 14 is at least partly surrounded, in the axial direction, by housing elements 42, 44 of a hand-held machine tool 36. The fan shaft 38 is mounted in said housing elements 42, 44. A driving motor, which is not represented, of the hand-held machine tool 36 drives the fan shaft 38 in a rotating manner during operation.

Claims (10)

  1. Claims 1. Hand-held machine tool fan with at least three fan blades (12) which have an at least partly identical effective region (14) during operation, characterised in that the fan blades (12) are arranged at irregular distances (16, 18) from one another and/or have effective surfaces (20) of differing construction.
  2. 2. Hand-held machine tool fan according to claim 1, characterised in that the fan blades (12) have intake edges (22) of differing construction.
  3. 3. Hand-held machine tool fan according to claim 1 or 2, characterised in that the fan blades (12) have output edges (24) of differing construction.
  4. 4. Hand-held machine tool fan according to one of the preceding claims, characterised in that the at least two fan blades (12) are arranged in pairs.
  5. 5. Hand-held machine tool fan according to one of the preceding claims, characterised in that the fan blades (12) are intended to move air substantially in the peripheral direction (26) of a fan axis (28)
  6. 6. Hand-held machine tool fan according to one of the preceding claims, characterised by a fan hub (30) which is intended to deflect a direction of airflow (32) by more than 45 degrees.
  7. 7. Hand-held machine tool fan according to one of the preceding claims, characterjsed in that a centre of gravity of the fan blades (12) is arranged close to a fan axis (28)
  8. 8. Hand-held machine tool fan according to one of the preceding claims, characterised by a stabilising ring (34) which fastens the fan blades (12) as least in the peripheral direction (26) of a fan axis (28).
  9. 9. Hand-held machine tool with a hand-held machine tool fan (10) according to one of the preceding claims.
  10. 10. Apparatus substantially as herein before described with reference to and as shown in the accompanying drawings.
GB1103949A 2010-03-09 2011-03-08 Fan blade spacing and/or construction Withdrawn GB2478646A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE102010002673A DE102010002673A1 (en) 2010-03-09 2010-03-09 Hand tools fan

Publications (2)

Publication Number Publication Date
GB201103949D0 GB201103949D0 (en) 2011-04-20
GB2478646A true GB2478646A (en) 2011-09-14

Family

ID=43923401

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1103949A Withdrawn GB2478646A (en) 2010-03-09 2011-03-08 Fan blade spacing and/or construction

Country Status (3)

Country Link
CN (1) CN102192188A (en)
DE (1) DE102010002673A1 (en)
GB (1) GB2478646A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2984971A1 (en) * 2011-12-21 2013-06-28 Seb Sa Wheel for centrifugal ventilator of deep fryer for cooking potato chips, has blades extended between lower longitudinal edge and upper longitudinal edge in direction of height of blade, where upper longitudinal edge exhibits concave profile
EP3842643A1 (en) * 2019-12-24 2021-06-30 Sunonwealth Electric Machine Industry Co., Ltd. Impeller and cooling fan including the impeller

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012215503B4 (en) 2012-08-31 2016-07-21 Siemens Aktiengesellschaft Rotor of an electric machine and electric machine
CN104275630A (en) * 2013-07-12 2015-01-14 南京德朔实业有限公司 Handheld sanding machine
CN104832459B (en) * 2014-02-10 2018-01-02 珠海格力电器股份有限公司 Fan and air conditioner comprising same
CN103967819B (en) * 2014-05-26 2016-08-24 浙江理工大学 A kind of 360 ° of fans of noise reduction
ITUB20152807A1 (en) * 2015-08-03 2017-02-03 Ma Ti Ka S R L FAN FOR OVENS FOR COOKING FOOD
CN108425882A (en) * 2018-05-31 2018-08-21 陈靖 A kind of electric hair dryer fan blade
CN108953236B (en) * 2018-07-17 2019-11-26 青岛永胜昌风机科技有限公司 A kind of rotor structure of centrifugal blower
CN108953222B (en) * 2018-08-16 2021-02-12 泛仕达机电股份有限公司 Centrifugal impeller

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Publication number Priority date Publication date Assignee Title
GB2046360A (en) * 1979-03-31 1980-11-12 Aes Plastics Ltd Fluid impeller
US20020108211A1 (en) * 2001-02-09 2002-08-15 Svoboda Steven J. Impeller for use with portable blower/vacuums
EP1253325A2 (en) * 2001-04-27 2002-10-30 Black & Decker Inc. Radial flow impeller

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Publication number Priority date Publication date Assignee Title
JP3391199B2 (en) * 1996-11-22 2003-03-31 日立工機株式会社 Centrifugal fan
JP2005246542A (en) * 2004-03-04 2005-09-15 Hitachi Koki Co Ltd Power tool
CN100540918C (en) * 2004-09-24 2009-09-16 松下电器产业株式会社 Cross flow fan
CN2748676Y (en) * 2004-11-23 2005-12-28 珠海格力电器股份有限公司 Fan impeller for air conditioner
DE102008001556A1 (en) * 2008-05-05 2009-11-12 Robert Bosch Gmbh Fan and method for operating a fan
CN201416570Y (en) * 2009-03-12 2010-03-03 上虞专用风机有限公司 Impeller of high-temperature centrifugal fan

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2046360A (en) * 1979-03-31 1980-11-12 Aes Plastics Ltd Fluid impeller
US20020108211A1 (en) * 2001-02-09 2002-08-15 Svoboda Steven J. Impeller for use with portable blower/vacuums
EP1253325A2 (en) * 2001-04-27 2002-10-30 Black & Decker Inc. Radial flow impeller

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2984971A1 (en) * 2011-12-21 2013-06-28 Seb Sa Wheel for centrifugal ventilator of deep fryer for cooking potato chips, has blades extended between lower longitudinal edge and upper longitudinal edge in direction of height of blade, where upper longitudinal edge exhibits concave profile
EP3842643A1 (en) * 2019-12-24 2021-06-30 Sunonwealth Electric Machine Industry Co., Ltd. Impeller and cooling fan including the impeller

Also Published As

Publication number Publication date
DE102010002673A1 (en) 2011-09-15
GB201103949D0 (en) 2011-04-20
CN102192188A (en) 2011-09-21

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