EP0040532A1 - Construction of fan blades - Google Patents
Construction of fan blades Download PDFInfo
- Publication number
- EP0040532A1 EP0040532A1 EP81302184A EP81302184A EP0040532A1 EP 0040532 A1 EP0040532 A1 EP 0040532A1 EP 81302184 A EP81302184 A EP 81302184A EP 81302184 A EP81302184 A EP 81302184A EP 0040532 A1 EP0040532 A1 EP 0040532A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- fan
- angle
- attack
- blades
- shape memory
- 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- Withdrawn
Links
Images
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
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/34—Blade mountings
- F04D29/36—Blade mountings adjustable
- F04D29/362—Blade mountings adjustable during rotation
- F04D29/368—Adjustment by differences of temperature
Definitions
- the present invention relates to fans, and in particular to fans suitable for cooling engines or motors.
- a rotary fan having blades constructed of shape memory material and capable of assuming a first angle of attack at temperatures below a threshold value and a second angle of attack, greater than the first, at a temperature above said threshold value.
- a fan which may be used for cooling an engine or motor, in which the blades have a small angle of attack at ambient temperatures, and due to being made of a shape memory material, for example shape memory brass or a copper-zinc-aluminium alloy known as "Betalloy N-1040" and manufactured by Raychem Inc. of California, U.S.A., will deform to give a normal fan angle of attack at a temperature above a particular threshold value.
- a threshold value suitable for use with an electric motor, is 50 to 70 o C.
- the fan is advantageously punched out from sheet metal shape memory material so as to have a disc form at ambient temperature.
- an elevated temperature for example 50 to 70°C, then provided that the fan has an appropriate construction history, the punched out blades of the disc will incline to the desired fan angle, so that air is projected over the windings of the motor.
- the "fan” when the motor starts off, the "fan" will be essentially disc-shaped, and will make substantially no noise.
- the motor itself will increase in temperature, and the fan will also increase in temperature, because it will be connected thereto directly.
- the fan blades will then begin to alter or form due to the shape memory characteristics of the metal, and this will project air over the armature, thus cooling it down.
- the motor operates at full speed, the actual rotation of the motor will itself induce . a cooling, and the current demand will be greatly reduced, in any event, so that the requirement for a fan will drop.
- the temperature of the armature will drop, and the "fan” will reassume its disc-like configuration, thus reducing significantly the noise.
- the angle of attack will, of course, then be zero. It is possible, however, for the blades to have a smaller than normal angle of attack at ambient temperature.
- the fan is initially formed (Fig. 1(a)) as a flat disc 1 with radial slots such as 2 defining the blades, such as 3, of the fan.
- a central boss 4 is provided, and this member may or may not be formed of shape memory material. It can be advantageous for the boss 4 to be formed of material of high thermal conductivity so as to assist heat flow to the vicinity of the blades.
- the blades are twisted, by cold or hot shaping, to form blades with a normal angle of attack for such fans (e.g.25° - 35 0 ).
- the so formed fan is then heated to give austenitic crystal structure (beta or parent phase) then rapidly cooled, or subjected to stress whose magnitude is related to temperature, to give crystal form of martensite.
- the fan is re-formed, at room temperature, into a disc-shaped plate (i.e. matensite under stress).
- the structure is "trained” by repeating several times the foregoing sequence of "betatizing”. quenching, deforming and then betatizing again.
- the fan' assumes its disc-like shape at relatively low temperatures but reverts to this fan-like form, with angle of attack 25 0 - 35°, when its temperature is raised to, say, 50°C to 70°C.
- a blade angle of 30° corresponds to:
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
Acooling fan for an engine or motor is constructed so that the blades, at least, are formed of shape memory material. The construction procedure is such as to cause the material to assume one condition, in which the angle of attack for the blades is relatively low, for temperatures below a threshold value and to assume another condition, in which the angle of attack of the blades is relatively high, fortemperatures above the threshold value.
Description
- The present invention relates to fans, and in particular to fans suitable for cooling engines or motors.
- It is very often advantageous for an engine, such as an internal combustion engine or for an electric motor to have a fan to cool it during operation. Nearly all electric motors are provided with such fans. One of the problems of electric motors provided with fans is that they generate a rather high noise level.
- According to the invention from one aspect there is provided a rotary fan having blades constructed of shape memory material and capable of assuming a first angle of attack at temperatures below a threshold value and a second angle of attack, greater than the first, at a temperature above said threshold value.
- According to the present invention, from another aspect a fan is provided, which may be used for cooling an engine or motor, in which the blades have a small angle of attack at ambient temperatures, and due to being made of a shape memory material, for example shape memory brass or a copper-zinc-aluminium alloy known as "Betalloy N-1040" and manufactured by Raychem Inc. of California, U.S.A., will deform to give a normal fan angle of attack at a temperature above a particular threshold value. An example of such a threshold value, suitable for use with an electric motor, is 50 to 70oC.
- The fan is advantageously punched out from sheet metal shape memory material so as to have a disc form at ambient temperature. When it is raised to an elevated temperature, for example 50 to 70°C, then provided that the fan has an appropriate construction history, the punched out blades of the disc will incline to the desired fan angle, so that air is projected over the windings of the motor.
- This is particularly advantageous with an electric motor, because the heating of the motor takes place mainly when under load at low speeds. The noise of the motor, however, is highest when the motor is operating at a high speed.
- Thus with the construction according to the present invention, when the motor starts off, the "fan" will be essentially disc-shaped, and will make substantially no noise. As the current builds up, the motor itself will increase in temperature, and the fan will also increase in temperature, because it will be connected thereto directly. The fan blades will then begin to alter or form due to the shape memory characteristics of the metal, and this will project air over the armature, thus cooling it down. When the motor operates at full speed, the actual rotation of the motor will itself induce . a cooling, and the current demand will be greatly reduced, in any event, so that the requirement for a fan will drop. Thus, when the motor operates at full speed, the temperature of the armature will drop, and the "fan" will reassume its disc-like configuration, thus reducing significantly the noise.
- If the fan is of disc form at ambient temperature, the angle of attack will, of course, then be zero. It is possible, however, for the blades to have a smaller than normal angle of attack at ambient temperature.
- A typical construction procedure for a fan in accordance with one example-of the invention will now be desoribed with reference to the accompanying drawings which show a fan in various stages of construction.
- The fan is initially formed (Fig. 1(a)) as a flat disc 1 with radial slots such as 2 defining the blades, such as 3, of the fan. A
central boss 4 is provided, and this member may or may not be formed of shape memory material. It can be advantageous for theboss 4 to be formed of material of high thermal conductivity so as to assist heat flow to the vicinity of the blades. - As shown in Figure 1(b), the blades are twisted, by cold or hot shaping, to form blades with a normal angle of attack for such fans (e.g.25° - 350).
- The so formed fan is then heated to give austenitic crystal structure (beta or parent phase) then rapidly cooled, or subjected to stress whose magnitude is related to temperature, to give crystal form of martensite.
- As the next step in the procedure, the fan is re-formed, at room temperature, into a disc-shaped plate (i.e. matensite under stress). The structure is "trained" by repeating several times the foregoing sequence of "betatizing". quenching, deforming and then betatizing again.
- When the construction procedure is complete, the fan' assumes its disc-like shape at relatively low temperatures but reverts to this fan-like form, with angle of attack 250 - 35°, when its temperature is raised to, say, 50°C to 70°C.
-
- where t represents the material's thickness,
- Z represents the blade root width
- ε represents the strain, and
- α represents the blade angle
- On the basis of the foregoing relationship, and assuming a certain maximum value for the strain factor (typically 3%) curves can be drawn of material thickness plotted against blade angle and it can be shown that different curves are produced by different blade root widths.
- For example, a blade angle of 30° corresponds to:
- (a) a material thickness of approximately 0.70mm for a blade root width of 6mm, or
- (b) a material thickness of approximately 1.50mm for a blade root width of 12mm, or
- (c) a material thickness of approximately 2.20mm for a blade root width of 18mm.
Claims (8)
1. A rotary fan having blades constructed of shape memory material and capable of assuming a first angle of attack at temperatures below a threshold value and a second angle of attack, greater than the first, at temperatures above said threshold value.
2. A fan according to Claim 1 wherein the shape memory material comprises shape memory brass.
3. A fan according to Claim 1 wherein the shape memory material comprises an alloy of copper, zinc and aluminuim, known as Betalloy N-1040.
4. A fan according to any preceding claim formed with a boss of high thermal conductivity.
5. A fan according to any preceding claim wherein said first angle of attack is substantially zero and said second angle of attack is in the range from 25° to 35 0.
6. A fan according to any preceding claim wherein the threshold value of temperature is in the range from 54°C to 70°C.
7. A fan, for cooling an engine or motor, in which the blades have a small angle of attack at ambient temperatures and deform to give a greater angle of attack at temperatures above a threshold value, wherein the blades are formed of a shape memory material.
8. A fan substantially as herein described.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8016582 | 1980-05-20 | ||
GB8016582 | 1980-05-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0040532A1 true EP0040532A1 (en) | 1981-11-25 |
Family
ID=10513531
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP81302184A Withdrawn EP0040532A1 (en) | 1980-05-20 | 1981-05-18 | Construction of fan blades |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0040532A1 (en) |
JP (1) | JPS5710798A (en) |
AU (1) | AU7068881A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2530886A1 (en) * | 1982-04-28 | 1984-01-27 | Mitsubishi Electric Corp | GENERATOR FOR A VEHICLE WITH A COOLING FAN |
GB2184168A (en) * | 1985-12-04 | 1987-06-17 | Mtu Muenchen Gmbh | Use of shape-memory alloy components to operate gas turbine engine elements |
EP1247992A1 (en) * | 2001-03-16 | 2002-10-09 | C.R.F. Società Consortile per Azioni | Fan or propeller, with shape memory |
EP2078865A2 (en) | 2008-01-09 | 2009-07-15 | Rosati Fratelli S.r.l. | Variable geometry fan and method for manufacturing the blades thereof |
US11668316B1 (en) * | 2022-01-07 | 2023-06-06 | Hamilton Sundstrand Corporation | Rotor formed of multiple metals |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5999098A (en) * | 1982-11-26 | 1984-06-07 | Matsushita Electric Ind Co Ltd | Ventilating device for air-conditioning machine |
JPS6127917U (en) * | 1984-07-23 | 1986-02-19 | 本田技研工業株式会社 | cooling fan |
JPS6365894U (en) * | 1986-10-20 | 1988-04-30 | ||
JPH0226697A (en) * | 1988-07-16 | 1990-01-29 | Nomura Kiko:Kk | Dehydration of sludgy substance |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2112261A1 (en) * | 1971-03-13 | 1972-09-14 | Battelle Institut E V | Cooling fan |
US3764227A (en) * | 1972-08-11 | 1973-10-09 | Hayes Albion Corp | Temperature sensitive fan |
FR2351446A1 (en) * | 1976-05-10 | 1977-12-09 | Delta Materials Research Ltd | TEMPERATURE SENSITIVE CONTROL UNIT |
-
1981
- 1981-05-18 AU AU70688/81A patent/AU7068881A/en not_active Abandoned
- 1981-05-18 EP EP81302184A patent/EP0040532A1/en not_active Withdrawn
- 1981-05-19 JP JP7561381A patent/JPS5710798A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2112261A1 (en) * | 1971-03-13 | 1972-09-14 | Battelle Institut E V | Cooling fan |
US3764227A (en) * | 1972-08-11 | 1973-10-09 | Hayes Albion Corp | Temperature sensitive fan |
FR2351446A1 (en) * | 1976-05-10 | 1977-12-09 | Delta Materials Research Ltd | TEMPERATURE SENSITIVE CONTROL UNIT |
GB1573204A (en) * | 1976-05-10 | 1980-08-20 | Delta Materials Research Ltd | Temperature responsive actuators |
Non-Patent Citations (1)
Title |
---|
Machine Design, Vol. 51, October 1979, Nr. 24 Cleveland, US D.T. CURRY: "New uses for Metals that Remember", pages 113-117 * pages 114,115 * * |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2530886A1 (en) * | 1982-04-28 | 1984-01-27 | Mitsubishi Electric Corp | GENERATOR FOR A VEHICLE WITH A COOLING FAN |
GB2184168A (en) * | 1985-12-04 | 1987-06-17 | Mtu Muenchen Gmbh | Use of shape-memory alloy components to operate gas turbine engine elements |
US4740138A (en) * | 1985-12-04 | 1988-04-26 | MTU Motoren-und Turbinen-Munchen GmbH | Device for controlling the throat areas between the diffusor guide vanes of a centrifugal compressor of a gas turbine engine |
US4752182A (en) * | 1985-12-04 | 1988-06-21 | Mtu Motoren-Und Turbinen-Munench Gmbh | Device for the open- or closed-loop control of gas turbine engines or turbojet engines |
GB2184168B (en) * | 1985-12-04 | 1989-10-11 | Mtu Muenchen Gmbh | Diffusor guide vane having a device for open-or closed-loop control of a gas turbine. |
EP1247992A1 (en) * | 2001-03-16 | 2002-10-09 | C.R.F. Società Consortile per Azioni | Fan or propeller, with shape memory |
EP2078865A2 (en) | 2008-01-09 | 2009-07-15 | Rosati Fratelli S.r.l. | Variable geometry fan and method for manufacturing the blades thereof |
US8092188B2 (en) | 2008-01-09 | 2012-01-10 | Rosati Fratelli S.R.L. | Variable geometry fan and method for manufacturing the blades thereof |
US11668316B1 (en) * | 2022-01-07 | 2023-06-06 | Hamilton Sundstrand Corporation | Rotor formed of multiple metals |
Also Published As
Publication number | Publication date |
---|---|
AU7068881A (en) | 1982-07-15 |
JPS5710798A (en) | 1982-01-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0040532A1 (en) | Construction of fan blades | |
US5403157A (en) | Heat exchange means for obtaining temperature gradient balance | |
EP0154090A1 (en) | Engine temperature control system | |
US6015263A (en) | Fluid moving device and associated method | |
EP0889211A3 (en) | Cooling control system and cooling control method for engine | |
US4890050A (en) | Automotive alternator | |
US4038955A (en) | Automatic choke systems for carburetors | |
US3764227A (en) | Temperature sensitive fan | |
FR2392521A1 (en) | CIRCUIT WITH PROTECTION AGAINST OVERLOADS FOR GRADUAL ADJUSTMENT OF THE POWER OF ELECTRIC FAN MOTORS | |
US2845869A (en) | Thermo-sensitive pump | |
US3968468A (en) | Electrical switch and method of calibrating | |
JPH06159099A (en) | Axial flow fluid machinery | |
JPS5755338A (en) | Ventilating fan with heat exchanger | |
JPS55119519A (en) | Damper | |
JPS5857100A (en) | Blade-tip clearance adjustment type axial-flow compressor | |
US2512342A (en) | Electric motor starting system | |
JPS5920521A (en) | Cooling system controller for water-cooled internal combustion engine | |
JPS6030499A (en) | Fan | |
US5159307A (en) | Electric motor protector | |
JPH07213091A (en) | Method of cooling power conversion device for electric car | |
DE1528887A1 (en) | Hydrodynamic or aerodynamic guide or conveyor element | |
EP0097606B1 (en) | Method of securing sleeve bearing lubrication of a multiple speed rotational device, control arrangement for carrying out said method, and use of said method and control arrangement in regulating a fan | |
JP2724815B2 (en) | Shape memory alloy coil spring and method of manufacturing the same | |
JPS58204999A (en) | Variable blade | |
JPS62142894A (en) | Blower |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): DE FR GB IT NL |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN |
|
18W | Application withdrawn |
Withdrawal date: 19820302 |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: PLACKETT, ANTHONY GEOFFREY |