EP0467336A2 - Axialgebläse mit umkehrbarer Strömungsrichtung - Google Patents
Axialgebläse mit umkehrbarer Strömungsrichtung Download PDFInfo
- Publication number
- EP0467336A2 EP0467336A2 EP91111960A EP91111960A EP0467336A2 EP 0467336 A2 EP0467336 A2 EP 0467336A2 EP 91111960 A EP91111960 A EP 91111960A EP 91111960 A EP91111960 A EP 91111960A EP 0467336 A2 EP0467336 A2 EP 0467336A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- casing
- drive motor
- wind
- rotating impeller
- impeller
- 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.)
- Granted
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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
- 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
- F04D19/00—Axial-flow pumps
- F04D19/002—Axial flow fans
- F04D19/005—Axial flow fans reversible fans
Definitions
- the present invention relates to a bi-directional axial-flow blower which is mounted, for example, near the ceiling of the tunnel of an automobile road for ventilating the tunnel.
- a bi-directional axial-flow blower generally referred to as a jet-fan is commonly used.
- Such type of well-known bi-directional blower is grouped in the following categories.
- An object of the invention is to provide a bi-directional axial-flow blower which requires no complex mechanism such as a rotor-reversing mechanism and employs a proper shape of rotor to enables air-blowing operation with high efficiency and low noise both in the forward and reverse directions.
- a bi-directional axial-flow blower of the present invention is constructed as follows:
- the wind is controlled to flow either in the forwardly direction or in the reverse direction by selectively operating one of the forward or reverse drive motor in accordance with the command for changing wind directions.
- the airfoil type rotors having camber suitable for the respective wind directions provide high blower efficiency in either directions.
- the impeller of the inoperative motor side is left free, so that the inoperative impeller receives air flow produced by the operative impeller to rotate free without adversely affecting the ventilation performance.
- the drive motor is, for example, of the reversible type in which the drive motor is operated either in the forward direction or in the reverse direction in accordance with the desired wind direction and the clutches inserted between the drive motor and impellers are engaged or disengaged in accordance with the desired wind direction, thereby changing the wind directions.
- the use of rotor having a camber offers high blower efficiency.
- the inoperative impeller disengaged form the drive motor by the clutch is freely rotated due to air flow produced by the operative impeller. Therefore, it will not adversely affect the ventilation performance.
- the impellers are driven into rotation in the same direction regardless of the desired direction of wind.
- the impellers and drive motor are also turned around together with the casing so that the wind flow is reversed.
- the use of airfoil rotor having a camber offers high blower efficiency.
- the stay vane converts a high rotating dynamic pressure produced at the outlet of the impeller into a static pressure for pressure recovery as well as controls the separation on the surface of stay vane.
- the wind pressure of blower is increased achieving highly efficient and low noise operation of the blower.
- the conical wind guide provided within the stationary casings form a wind path whose cross section continuously grows smaller(upstream) toward and larger(downstream) from the boss of impeller and the drive motor which are incorporated within the casing adjacent to the fixed casing.
- This permits the smooth acceleration and deceleration of the air flowing through the bore of casing, retarding the occurrence of separation.
- the conical wind guide in the stationary casing arranging is separated from the casing in which the impeller and drive motor are incorporated, thus achieving a short and small casing that rotates in accordance with the desired wind direction. This is particularly advantageous in that adjacent casings will not interfere each other during rotation even if a plurality of blowers for ventilation are suspended from the tunnel ceiling side by side in a narrow space.
- FIGs. 1 - 3 show an embodiment according to first aspect of the invention.
- reference numeral 1 denotes a blower supported from the ceiling of tunnel 2.
- the blower 1 comprises a hollow cylindrical casing 3 opening at two ends thereof, an inner hollow cylinder 5 mounted in the middle of the casing 3 by means of a stay 4, a forward drive motor 6 and a reverse drive motor 7 housed in the inner hollow cylinder 5 on the same axis thereof, and a forwardly-rotating impeller 8 and a reversely-rotating impeller 9 coupled to the output shafts of the respective motors 6 and 7, respectively.
- Reference numeral 10 denotes a controller for controlling the wind direction
- 8a and 9a denote rotors of the impellers
- 8b and 9b denote cones enclosing the ends of the impellers.
- the rotors 8a and 9a of aforementioned impellers 8 and 9 have a camber shown in Figs. 3(a) and 3(b) (curved rotor whose thickness grows thinner toward the rear edge of the rotor plate or circular-arc plate whose thickness is constant along the camber line of rotor), and are disposed with respective orientation in accordance with the rotational directions of the forward and reverse motors 6 and 7 as shown by arrows a and b.
- the forward drive motor 6 is operated to drive the forwardly-rotating impeller 8 into rotation in the direction of the arrow a of Fig.
- the command is supplied to the controller 10 so as to change the wind direction.
- the forward drive motor 6 is stopped and the reverse drive motor 7 is started so as to drive the reversely-rotating impeller 9 into rotation in the direction of the arrow b of Fig. 3(b).
- the impeller 9 directly coupled to the inoperative motor 8 is free, so that it receives the air flow B to rotate free.
- the inner hollow cylinder 5 may be omitted and the forward drive motor 6 and the reverse drive motor 7 may be mounted within the casing 3 by the means of the stay 4.
- the dual-rotor type motor in which two rotors are assembled into a common stator may be used in place of two independent motors such as the motor 6 for driving the forwardly-rotating impeller and the motor 7 for driving contrarotating impeller.
- the inner hollow cylinder 5 may be omitted and the drive motor may be directed mounted in the casing 3 by means of the stay 4.
- the cones 8b and 9b are mounted to the impellers 8 and 9, the cones may be separated from the impellers and fixed in the casing 3.
- the rotor 8a of the forwardly-rotating impeller 8 and the rotor 9a of the reversely-rotating impeller 9 are oriented 180 degrees opposite to each other and the drive motor 6 runs in the direction of a and the drive motor 7 in the direction of b.
- a modification can be made such that the rotors 8a and 9a are oriented differently as shown in Fig. 4 and the drive motors 6 and 7 may be rotated in the same direction, a and b.
- Fig. 5 shows an embodiment according to second aspect of the invention.
- a reversible drive motor 11 (double loaded) is used in the place of the forward and reverse drive motors 6 and 7 of the first embodiment.
- To the two ends of shaft extending outwardly of the motor 11 are coupled the forwardly-and reversely-rotating impellers 8 and 9 via clutches 12 and 13 electromagnetically operated.
- the shape and orientation of the rotors of the impellers 8 and 9 are the same as those in Figs. 3(a) and 3(b).
- the drive motor 11 is of a reversible type and runs to rotate the impellers 8 and 9 either in the direction a or in the direction b in accordance with the desired wind direction A or B
- the rotors 8a and 9a of the impellers 8 and 9 may be cascaded as shown in Fig. 4 so that the impellers 8 and 9 can rotate in the same direction without regard to the desired wind directions A or B.
- the use of this construction allows that a ordinary double-loaded drive motor that rotates in a fixed direction may be used in place of the reversible type drive motor 11.
- Figs. 6-8 show an embodiment according to third and fourth aspect of the invention.
- a drive motor 15 supported by means of a stay vane 14 and an impeller 16 coupled to the output shaft of the drive motor 15.
- the casing has a wind inlet 3a, a wind outlet 3b, an impeller 16 disposed upstream of the drive motor 15.
- a cone 17 for guiding the wind is mounted at the front end of the impeller 16 and a cone 18 at the rear end of the drive motor 15.
- the casing 3 is mounted to a motor shaft 19a of a wind-direction selecting motor 19 for selecting the wind direction such that the casing is suspended from the motor 19 mounted on the ceiling.
- the casing 3 is rotated about the shaft 19a in the direction of the arrow C.
- the impeller 16 has an airfoil type rotor 16a having a camber.
- the orientation of rotor blades relative to the rotational direction a is that shown in Fig. 8.
- the stay vane 14 aligned downstream of the rotor 16a is formed with a curved surface, so that the cross section of the stay vane is such that the angle 0 with respect to the central axis O of the casing 3 decreases from front edge to rear edge.
- the casing 3 When the wind is delivered from right to left with the drive motor 15 rotated in the direction a, the casing 3 is rotated by the wind-direction selecting motor 19 so as to change the orientation of the casing 3 by 180 degrees from the position in Fig. 6 to that in Fig. 7.
- the inlet 3a of the casing 3 is oriented to the right and an air flow is produced in the direction B within the casing 3.
- the stay vane 14 holding the motor 15 is formed to have the aforementioned cross section so that the stay vane 14 retards the separation of wind flowing along the stay vane 14 and absorbs the dynamic pressure due to the rotating velocity produced by the impeller 16 to convert it into the static pressure.
- the cones 17 and 18 provided at the front end of the impeller 16 and at the rear end of the drive motor 15, respectively, allow the smooth change of flow rate of air flow contributing to the retardation of separation.
- Figs. 9 and 10 show a variation of the third embodiment as an embodiment of the fifth aspect of the invention.
- the drive motor 15 and impeller 16 are assembled just as in the third embodiment.
- a stationary casings 20 are suspended from the ceiling by means of wires 21 such that the stationary casings 20 are in line with the casing 3 and are disposed at the front of and at the rear of the casing 3.
- a long conical wind guide 22 is mounted by means of the stays 23 so that the cross section of the wind path varies continuously toward the drive motor 15 and the front end of impeller 16.
- the inlet and outlet of the casing 3 and the ends of the stationary casings 20 opposing the casing 3 are formed in an arcuate shape in concentric relation with the motor shaft 19a of the wind-direction selecting motor 19.
- the casings are opposing each other with slight clearances therebetween.
- the conical wind guide mounted to the stationary casing 20 smooths out the change in wind velocity just as in the third embodiment so as to control the occupance of separation.
- the casing 3 is allowed to rotate free in the direction of the arrow C without interfering with the stationary casings 20.
- Mounting the long conical wind guide 22 to the stationary casing 20 separately from the casing 3 permits a smaller size of the casing 3 which incorporates the drive motor 15 and impeller 16 therein. This minimizes the projection of the casing 3 to the sideway when the casing 3 is rotated.
- the adjacent blowers may be spaced apart only by short distance between them without interference.
- a bi-directional type axial-flow blower according to the present invention is of the aforementioned constructed and has the following advantages.
- the rotor of impeller is constructed of the airfoil blade having a camber and the forward and reverse drive motor is selectively operated to achieve the forward and reverse flow of wind for high efficiency wind production.
- the impeller requires no complex mechanism for changing the orientation of rotor blades ensuring high reliability.
- the rotor of impeller is constructed of the airfoil blade having a camber as the first aspect and the clutch is operated to select either forward wind direction or reverse wind direction thereby achieving highly efficient wind production.
- the orientation of the casing in which the impeller and drive motor are assembled is reversed in accordance with the desired wind direction.
- a complex mechanism for changing the orientation of rotor blade is not required while the wind direction can be switched between the forward and reverse directions by rotating the casing with both the direction of rotor blade cascade and the motor direction unchanged.
- the impeller is disposed upstream of the wind in the casing and the drive motor downstream while at the same time the drive motor is mounted to the casing by means of a stay vane whose cross section is such that the angle with respect to the center axis of casing decreases from front edge to rear edge.
- the stationary casing having a wind path is disposed adjacent the casing, which has the impeller and drive motor assembled therein, in such a away that the wind path communicates with the casing.
- the conical wind guide is provided within the stationary casing on the central axis. This allows the change in wind velocity to be smoothed out for high efficiency and low noise as well as achieves the smallest possible casing that is rotated to be oriented in accordance with the wind direction.
- the blower is advantageous in that if the blower is used for the ventilation in the tunnel where a plurality of blowers are to be aligned in a small space near the ceiling, the casings of adjacent blowers will not interfere each other when the casings are rotated.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP94102599A EP0606108B1 (de) | 1990-07-18 | 1991-07-17 | Axialgebläse mit umkehrbaren Strömungsrichtung |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18986890 | 1990-07-18 | ||
| JP189868/90 | 1990-07-18 | ||
| JP2254498A JP2712800B2 (ja) | 1990-07-18 | 1990-09-25 | 正逆双方向型軸流送風機 |
| JP254498/90 | 1990-09-25 |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP94102599.1 Division-Into | 1994-02-21 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0467336A2 true EP0467336A2 (de) | 1992-01-22 |
| EP0467336A3 EP0467336A3 (en) | 1992-04-15 |
| EP0467336B1 EP0467336B1 (de) | 1995-04-26 |
Family
ID=26505731
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19910111960 Expired - Lifetime EP0467336B1 (de) | 1990-07-18 | 1991-07-17 | Axialgebläse mit umkehrbarer Strömungsrichtung |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP0467336B1 (de) |
| DE (2) | DE69125037T2 (de) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2150031C1 (ru) * | 1998-10-12 | 2000-05-27 | Открытое акционерное общество "Ракетно-космическая корпорация "Энергия" им. С.П. Королева" | Дублированный электровентилятор |
| US8932013B2 (en) | 2011-10-05 | 2015-01-13 | Twin City Fan Companies, Ltd. | Guide vane and inline fan assembly |
| CN109458663A (zh) * | 2018-11-16 | 2019-03-12 | 广东美的制冷设备有限公司 | 空调挂机和具有其的空调器 |
| CN109973869A (zh) * | 2019-03-07 | 2019-07-05 | 广州市沙唯士电子科技有限公司 | 一种用于煤矿的便于散热的除尘型开采设备 |
| US10519957B2 (en) * | 2013-10-14 | 2019-12-31 | Continental Automotive Gmbh | Pump |
| EP3789617A1 (de) * | 2019-09-03 | 2021-03-10 | Ziehl-Abegg Se | Ventilator |
| RU216449U1 (ru) * | 2022-10-24 | 2023-02-06 | Общество с ограниченной ответственностью Новосибирский энергомашиностроительный завод "ТАЙРА" | Устройство для передачи энергии вращения |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE484254A (de) * | ||||
| DE72180C (de) * | GG. RUDOLF & ClE in Feuerbach bei Stuttgart | Saugend oder drückend wirkende Ventilationsvorrichtung mittelst eines durch Wasserdruck betriebenen Ventilators | ||
| DE431682C (de) * | 1924-06-05 | 1926-07-20 | Siemens Schuckertwerke G M B H | Ventilator fuer umkehrbare Luftfoerderung |
| US1932231A (en) * | 1930-02-28 | 1933-10-24 | Westinghouse Electric & Mfg Co | Propeller type fluid translating device |
| US2555576A (en) * | 1946-05-07 | 1951-06-05 | Buffalo Forge Co | Axial flow fan |
| US3089637A (en) * | 1960-05-02 | 1963-05-14 | Chrysler Corp | Air circulating system and blower structure |
| WO1980000475A1 (en) * | 1978-08-16 | 1980-03-20 | Colchester Woods | Axial flow fans |
| FR2531501A1 (fr) * | 1982-08-03 | 1984-02-10 | Olivier Gilbert | Appareil combine ventilateur-distributeur d'air a plusieurs voies |
| DE3938975C1 (en) * | 1989-11-24 | 1990-12-06 | Wsp Ingenieurgesellschaft Fuer Waermetechnik, Stroemungstechnik Und Prozesstechnik Mbh, 5100 Aachen, De | Gas feed for process plant - uses identical fans and housings to give equal efficiency in either direction |
-
1991
- 1991-07-17 DE DE1991625037 patent/DE69125037T2/de not_active Expired - Fee Related
- 1991-07-17 DE DE1991609198 patent/DE69109198T2/de not_active Expired - Fee Related
- 1991-07-17 EP EP19910111960 patent/EP0467336B1/de not_active Expired - Lifetime
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2150031C1 (ru) * | 1998-10-12 | 2000-05-27 | Открытое акционерное общество "Ракетно-космическая корпорация "Энергия" им. С.П. Королева" | Дублированный электровентилятор |
| US8932013B2 (en) | 2011-10-05 | 2015-01-13 | Twin City Fan Companies, Ltd. | Guide vane and inline fan assembly |
| US10519957B2 (en) * | 2013-10-14 | 2019-12-31 | Continental Automotive Gmbh | Pump |
| CN109458663A (zh) * | 2018-11-16 | 2019-03-12 | 广东美的制冷设备有限公司 | 空调挂机和具有其的空调器 |
| CN109973869A (zh) * | 2019-03-07 | 2019-07-05 | 广州市沙唯士电子科技有限公司 | 一种用于煤矿的便于散热的除尘型开采设备 |
| EP3789617A1 (de) * | 2019-09-03 | 2021-03-10 | Ziehl-Abegg Se | Ventilator |
| RU216449U1 (ru) * | 2022-10-24 | 2023-02-06 | Общество с ограниченной ответственностью Новосибирский энергомашиностроительный завод "ТАЙРА" | Устройство для передачи энергии вращения |
| RU2805716C1 (ru) * | 2022-10-24 | 2023-10-23 | Общество с ограниченной ответственностью Новосибирский энергомашиностроительный завод "ТАЙРА" | Устройство для передачи энергии вращения |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0467336A3 (en) | 1992-04-15 |
| DE69109198T2 (de) | 1995-08-31 |
| DE69125037T2 (de) | 1997-06-12 |
| DE69109198D1 (de) | 1995-06-01 |
| DE69125037D1 (de) | 1997-04-10 |
| EP0467336B1 (de) | 1995-04-26 |
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