Title of Invention	AXIAL FAN WITH ANGLED BLADES
Abstract	An axial fan (1) rotating in a plane (XY) about an axis (2) comprises a central hub (3), a plurality of blades (4), which have a root (5) and a tip (6), the blades (4) being delimited by a convex leading edge (7) and by a concave trailing edge (8), their projections in the fan rotation plane each being formed by circular arc segments; the blades (4) are made from sections with aerodynamic profiles, each with decreasing length and more curved from the perimeter to the hub.

Title of Invention

AXIAL FAN WITH ANGLED BLADES

Abstract

An axial fan (1) rotating in a plane (XY) about an axis (2) comprises a central hub (3), a plurality of blades (4), which have a root (5) and a tip (6), the blades (4) being delimited by a convex leading edge (7) and by a concave trailing edge (8), their projections in the fan rotation plane each being formed by circular arc segments; the blades (4) are made from sections with aerodynamic profiles, each with decreasing length and more curved from the perimeter to the hub.

Full Text	WO 2006/006043 PCT/IB2005/001898 1 AXIAL FAN Description Technical Field The present invention relates to an axial fan with blades angled in the fan plane of rotation. The fan according to the present invention may be used in various applications, for example, to move air through a heat exchanger, or radiator, of a cooling system for the engine of a motor vehicle or the like; or to move air through the heat exchanger of the heating system and/or through the evaporator of the air conditioning system of the interior of a motor vehicle. Moreover, the fan according to the present invention may be used to move air in fixed air conditioning or heating systems for houses. Background Art Fans of this type must satisfy various requirements, including: low noise level, high efficiency, compactness, capacity to achieve good pressure and flow rate values. In particular, achieving good general performance while keeping noise levels down requires careful design of the blades and the profiles of which they consist. A fan of this type is known from United States patent US-6 241 474, which describes a low noise fan with blades whose angle or pitch decreases gradually from the hub to the tip over a predetermined extension of the radius, then their angle increases again towards the tip. The blades are connected to one another by an external ring. Disclosure of the Invention One aim of the present invention is to provide a fan which has good general performance with a low noise level. WO 2006/006043 PCT/IB2005/001898 2 According to one aspect of the present invention, an axial fan as specified in claim 1 is presented. The dependent claims refer to preferred and advantageous embodiments of the invention. Brief Description of the Drawings The invention is described in more detail below with reference to the accompanying drawings, which illustrate a preferred, non-limiting embodiment, in which: Figure 1 is a front view of the fan in accordance with the present invention; Figure 2 is a schematic front view of a blade of the fan illustrated in the previous figure; Figure 3 is a cross-section of several profiles at various fan diameters; and Figure 4 is a cross-section of a profile and the respective geometric characteristics. Detailed description of the Preferred Embodiments of the Invention With reference to the accompanying drawings, the fan 1 rotates about an axis 2 and comprises a central hub 3 to which a plurality of blades 4 are connected, the blades being curved in the fan 1 plane of rotation XY. The blades 4 have a root 5, a tip 6 and are delimited by a convex leading edge 7 and a concave trailing edge 8. For the best results in terms of efficiency, flow rate and air pressure, the fan 1 rotates with a direction of rotation V, illustrated in Figures 1 and 4, so that the tip 6 of each blade 4 encounters the air flow after the root 5. Maintaining the direction of rotation V, the fan 1 can be produced as a blowing fan or as a suction fan, by suitably modifying and adapting the profiles of the blades. The following description refers to a blowing fan by way of example. Figure 2 illustrates an example of the geometric characteristics of a blade 4: the leading edge 7 is delimited by two circular arc segments 9, 10, and the trailing edge 8 is delimited by one circular arc segment 11. In the leading edge 7, a WO 2006/006043 PCT/1B2005/001898 3 radius labelled Rl is the point of change from one circular arc segment to the other circular arc segment. According to the example in Figure 2, the general dimensions of the projection of a blade 4 in the plane XY are summarised in table 1: Table 1 - dimensions of a blade 4. Radius of internal segment (mm) Radius of change (mm) Radius of external segment (mm) Leading edge (Ref. 7) 133.57 (Ref. 9) 97.75 (Ref. Rl) 83.23 (Ref. 10) Radius (mm) Trailing edge (Ref. 8) S7.25 (Ref. 11) The general geometric characteristics of the blade 4 are defined relative to a hub with 110 mm diameter, that is to say, the blade 4 has a minimum radius Rmin = 55 mm at the root 5, and a 3 02 mm external diameter, giving it a maximum radius Rmax = 151 mm at the tip 6, meaning that the blade 4 has a 96 mm radial extension. As illustrated in the accompanying drawings, the outside of the fan may be fitted with a connecting ring 12 which may be several millimetres thick, meaning that the fan 1 in the example embodiment provided has an overall diameter of approximately 310 mm. As is known, one of the functions of the connecting ring is to stiffen the outer part of the blades 4 so as to promote maintenance of the angles of angles of incidence and to improve the aerodynamic performance of the outer profiles of the blades, reducing the formation of vortices at the tip 6 of the blades 4. However, it should be noticed that good results were also achieved using a fan made according to the present invention without the connecting ring. Considering that the blade 4 has a minimum radius Rmin = 55 mm and a maximum radius Rmax = 151 mm, the leading edge 7 has a radius Rl, where the change in the circular arc occurs, corresponding to around 44% of the radial extension of the leading edge 7, an extension which, as already indicated, is 96 mm. The part 9 of the leading edge 7 closest to the root 5 consists of a circular arc with a radius equal to around 88% of the WO 2006/006043 PCT/IB2005/001898 4 radius Rmax, and the part 10 of the leading edge 7 closest to the tip 6 consists of a circular arc segment with a radius equal to around 55% of the radius Rmax of the blade 4. As regards the trailing edge 8, the circular arc segment 11 has a radius equal to around 44.5% of the radius Rmax of the blade 4. The dimensions in percentages are summarised in table 2: Table 2 - blade 4 dimensions in percentage form. Internal segment radius (% ofRmax) Change radius (% of blade extension = Rmax-Rmin) External segmentradius (% of Rmax) Leading edge (Ref. 7) 88 (Ref. 9) 44 (Ref. Rl) 55 (Ref. 10) Radius (% of Rmax) Trailing edge (Ref. 8) 44.5 (Ref. 11) Satisfactory results in terms of flow rate, pressure and noise were achieved even with values around these percentage dimensions. In particular, variations of 10% more or less on the above-mentioned dimensions are possible. The percentage ranges relative to the dimensions are summarised in table 3: Table 3 - Blade 4 edges percentage ranges. Internal segment radius {% of Rmax) Change radius {% of blade extension = % of Rmax-Rmin) External segment radius {% of Rmax) Leading edge (Ref. 7) 79 - 97 (Ref. 9) 40 - 48.5 (Ref. Rl) 49.5 - 60.5 (Ref. 10) Radius (.% Rmax) Trailing edge (Ref. 8) 40 - 49 (Ref. 11) For the leading edge 7, in the circular arc segment change zone, there may be a suitable fillet so that the edge 7 is continuous and free of cusps. As regards the width or angular extension of the blades, again with reference to Figure 2, the projection of the blade 4 in the plane XY has an amplitude, at the root 5, represented by an angle Bl of around 60 degrees and an amplitude, at the tip 6, represented WO 2006/006043 PCT/IB2005/001898 5 by an angle B2 of around 2 6 degrees. Again, satisfactory results were achieved in terms of flow rate, pressure and noise with values of angles Bl, B2 around these values. In particular, variations of 10% more or less than the angles indicated are possible. The angle Bl may vary from 54 to 66 degrees, whilst the angle B2 may vary from 23 to 29 degrees. In general, it must also be considered that, due to the plastic material used to make fans, variations in all of the dimensions and angles of 5% more or less must all be considered within the values indicated. Considering the respective bisecting lines and following the fan 1 direction of rotation V, the tip 6 is further back than the root 5 by an angle B3 of around 26 degrees. Other angles characteristic of the blade 4 are angles B4, B5, B6, B7 (Figure 2) formed by the respective tangents to the two edges 7, 8 and by the respective lines passing through points M, N, S, T: the angles B4 and B5 are respectively 28 and 54 degrees and the angles B6, B7 are respectively 28 and 45 degrees. There may be between three and seven blades 4 and, according to a preferred embodiment, there are five blades 4 and they are separated by equal angles. Each blade 4 consists of a set of aerodynamic profiles which gradually join up starting from the root 5 towards the tip 6. Figure 3 illustrates seven profiles 13 - 19, relative to respective sections at various intervals along the radial extension of a blade 4. The profiles 13 - 19 are also formed by the geometric characteristics of which an example is provided in Figure 4 for one of the profiles. As illustrated in Figure 4, each profile 13 - 19 is formed by a continuous centre line Ll without points of inflection or cusps and by a chord L2. Each profile 13 - 19 is also formed by two angles BLE, BTE of incidence with the leading edge and with the trailing edge, said angles formed by the respective tangents to the centre line Ll at the point of intersection with the leading edge and with the trailing edge and a respective straight line perpendicular to the plane XY passing through the corresponding points of intersection. WO 2006/006043 PCT/IB2005/001898 6 With reference to the seven profiles 13 - 19, table 4 below indicates the angles of the leading edge BLE and of the trailing edge BTE, the length of the centre line LI and the chord L2 of the profiles of a blade 4. Table 4 - Radial position, angles of leading and trailing edges, length of centre line and chord of the profiles of a blade 4. Profile Radial extension (%> Radius (mm) BLE (degrees) BTE (degrees) LI (centre line mm) L2 (chord mm) 13 0 55 78.47 55.15 64.12 63.66 14 17.9 72.15 81.38 49.31 65.37 64.53 15 44.5 97.75 82.93 48.46 69.40 68.30 16 71.2 123.35 83.53 51.96 73.28 73.31 17 81.5 133.27 83.99 53.96 73.95 73.04 18 97.9 148.95 84.82 54.96 72.63 71.64 19 100 151 85.28 54.85 72.18 71.14 It should be noticed that the thickness of each profile 13 -19, according to a typical trend of wing-shaped profiles, initially increases, reaching a maximum value S-MAX at around 40% of the length of the centre line Ll, then it gradually decreases as far as the trailing edge 8. In percentages, the thickness S-MAX is around 1.6% of the radius Rmax; the thickness of the profiles is distributed symmetrically relative to the centre line Ll. The positions of the profiles 13 - 19 relative to the radial extension of a blade 4 and the relative values for the thickness, trend according to their position with respect to the centre line Ll are summarised in table 5. Table 5 - Radial position and thickness trend of blade 4 profiles. Profile Extension (%) Radius (mm) Thickness S-MAX (mm) dimensionless relative to S-MAX 0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll 13 0 55 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2 14 17.9 72.15 2.45 0.681633 0.967347 2 0.808163 0.534694 0.2 15 44.5 97.75 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2 16 71.2 123.35 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2 17 81.5 133.27 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2 18 97.9 148.95 2.45 0.5 31633 0.967347 1 0.808163 0.534694 0.2 19 100 151 2.45 0.681633 0.967347 1 0.808163 0.53461 I 0.2 WO 2006/006043 PCT/IB2005/001898 7 Table 6 below summarises the actual mm values of the trend of thicknesses according to their position with respect to the centre line Ll for each profile 13 - 19 with reference to the embodiment illustrated. Table 6 - Thickness trend in mm of blade 4 profiles 13 - 19. Profile Thickness (mm) 0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll 13 1.67 2.37 2.45 1.98 1.31 0.49 14 1.67 2.37 2.45 1.98 1.31 0.49 15 1.67 2.37 2.45 1.98 1.31 0.49 16 1.67 2.37 2.45 1.98 1.31 0.49 17 1.67 2.37 2.45 1.98 1.31 0.49 18 1.67 2.37 2.45 1.98 1.31 0.49 19 1.67 2.37 2.45 1.98 1.31 0.49 The profiles 13 - 19 are preferably delimited with a semicircular fillet, on the leading edge 7 side, and with a truncation created using a segment of a straight line on the trailing edge 8 side. In an alternative embodiment, good general performance was achieved in terms of the noise, flow rate and pressure supplied by the fan disclosed even with thicker profiles. According to said alternative embodiment, the positions of the profiles 13 - 19 relative to the radial extension of a blade and the relative thickness trend values according to their position with respect to the centre line Ll are summarised in table 7. It should also be noticed that, in this embodiment, the thickness S-MAX is reached at 30% of the length of the centre line Ll. Table profiles. 7 - Radial position and thickness trend of blade 4 Profile Extension (%) Radius (mm) Thickness S-MAX (mm) dimensionless relative to S-MAX 0% Ll 20% Ll 40% Ll 60%Ll 80% Ll 100% Ll 13 0 55 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125 14 17.9 72.15 3.98 0.42 0.9486 0.9667 0.75 0.46 0.125 15 44.5 97.75 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125 16 71.2 123.35 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125 17 84.5 136.15 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125 18 97.9 148.95 3.98 0.42 0.9486 0.9667 0.75 . 0.46 0.125 19 100 151 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125 Table 8 below summarises the actual mm values of the trend of WO 2006/006043 PCT/1B28 8 thicknesses according to their position with respect to the centre line LI for each profile 13 - 19 relative to the embodiment illustrated in the accompanying drawings. Table 8 - Thickness trend in mm of blade 4 profiles 13 - 19. Profile Thickness (mm) 0% LI 20% LI 40% LI 60% LI 80% LI 100% LI 13 1.67 3.77 3.85 2.99 1.83 0.49 14 1.67 3.77 3.85 2.99 1.83 0.49 15 1.67 3.77 3.85 2.99 1.83 0.49 16 1.67 3.77 3.85 2.99 1.83 0.49 17 1.67 3.77 3.85 2.99 1.83 0.49 18 1.67 3.77 3.85 2.99 1.83 0.49 19 1.67 3.77 3.85 2.99 1.83 0.49 As may be seen, in both embodiments, the profiles 13 - 19 have the same thickness in the corresponding positions (0% of LI, 20% of LI, ..., 80% of LI, etc.) along the extension of the centre line Ll. The first embodiment with the thinner profiles has advantages in terms of lightness, cost and ease of moulding. The second embodiment with the thicker profiles has advantages in terms of aerodynamic efficiency, since the thicker profiles have better performance to prevent stalling. The invention described may be subject to modifications and variations without thereby departing from the scope of the inventive concept described in the claims herein. WO 2006/006043 PCT/IB2005/001898 9 LIST OF REFERENCE CHARACTERS Reference Description 1 AXIAL FAN 2 AXIS OF ROTATION 3 CENTRAL HUB 4 FAN 1 BLADE 5 BLADE 4 ROOT 6 BLADE 4 TIP 7 CONCAVE LEADING EDGE 8 CONVEX TRAILING EDGE 9 CIRCULAR ARC SEGMENT (INTERNAL) 10 CIRCULAR ARC SEGMENT (EXTERNAL) 11 CIRCULAR ARC SEGMENT 12 CONNECTING RING 13-19 AERODYNAMIC PROFILES XY ROTATION PLANE V DIRECTION OF ROTATION Rl RADIUS OF CHANGE BETWEEN SEGMENTS 9 AND 10 XY PROJECTION IN THE PLANE Bl - B7 BLADE 4 CHARACTERISTIC ANGLES M, N, S, T BLADE 4 CHARACTERISTIC POINTS LI CENTRE LINE L2 CHORD BLE LEADING EDGE ANGLES OP INCIDENCE BTE TRAILING EDGE ANGLES OF INCIDENCE WO 2006/006043 PCT/JB2G05/001898 10 Claims 1. An axial fan (1), rotating in a direction (V) in a plane (XY) about an axis (2), comprising a central hub (3) with a radius (Rmin) , a plurality of blades (4) each, having a root (5) , a tip (6) which extends to a tip radius (Rmax) , the blades (4) being delimited by a convex leading edge (7) and a concave trailing edge (8), the axial fan being characterised in that the leading edge (7) comprises a first circular arc segment (9) close to the root (5) with a radius of between 79% and 97% of the tip radius (Rmax) and a second circular arc segment (10) close to the tip (6) with a radius of between 49.5% and 60.5% of the tip radius (Rmax), and a radius at the change between the two circular arc segments (9, 10) of between 40% and 48.5% of the extension (Rmax - Rmin) of the blade (4). 2. The axial fan (1) according to claim 1, characterised in that the trailing edge (8) comprises a circular arc segment (11) with a radius of between 40% and 49% of the tip radius (Rmax). 3. The axial fan (1) according to claim 1 or 2, characterised in that the leading edge (7) comprises a first circular arc segment (9) close to the root (5) with a radius which is 88% of the tip radius (Rmax) and a second circular arc segment (10) close to the tip (6) with a radius which is 55% of the tip radius (Rmax) , and a radius at the change between the two circular arc segments (9, 10) which is 44% of the extension (Rmax - Rmin) of the blade (4). 4. The axial fan (1) according to any of the foregoing claims, characterised in that the trailing edge (8) comprises a circular arc segment (11) with a radius which is 44.5% of the tip radius (Rmax) . 5. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane WO 2006/006043 PCT/IB2005/001898 11 (XY) has an amplitude, at the root (5) , with an angle (Bl) of between 54 and 66 degrees. 6. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) has an amplitude, at the tip (6) , with an angle (B2) of between 23 and 29 degrees. 7. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) has an amplitude, at the root (5) , with an angle (Bl) of around SO degrees. 8. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) has an amplitude, at the tip (6), with an angle (B2) of around 26 degrees. 9. The axial fan (1) according to any of the foregoing claims, characterised in that, considering the projection of the blade (4) in the plane (XY) and fan (1) direction of rotation (V) , the tip (6) is further back than the root (5) by an angle (B3) of around 26 degrees. 10. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) forms a point (M) of intersection between the leading edge (7) and the hub (3) with an angle (B4) of 28 degrees, the angle (B4) being formed by the respective tangent to the leading edge (7) at the point (M) and by a respective line from the axis (2) of the fan (1) passing through the point (M). 11. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) forms a point (N) of intersection between the leading edge (7) and the tip (6) with an angle (B5) of 54 degrees, the angle (B5) being formed by the respective tangent to the leading edge (7) at WO 20(16/006043 PCT/LB2005/001898 12 the point (N) and by a respective line from the axis (2) of the fan (1) passing through the point (N). 12. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) forms a point (S) of intersection between the trailing edge (8) and the hub (3) with an angle (B6) of 28 degrees, the angle (B6) being formed by the respective tangent to the trailing edge (8) at the point (S) and by a respective line from the axis (2) of the fan (1) passing through the point (S). 13. The axial fan (1) according to any of the foregoing claims, characterised in that the projection of the blade (4) in the plane (XY) forms a point (T) of intersection between the trailing edge (8) and the tip (6) with an angle (B7) of 45 degrees, the angle (8) at the point (T) and by a respective line from the axis (2) of the fan (1) passing through the point (T). 14. The axial fan (1) according to any of the foregoing claims, characterised in that the blade (4) consists of at least several aerodynamic profiles (13 - 19) relative to respective sections at various intervals along the radial extension of a blade (4), each profile (13 - 19) being formed by a centre line (LI) which is continuous and without points of inflection or cusps and by two angles (BLE, BTE) of incidence with the leading edge and the trailing edge, the angles being formed by the respective tangents to the centre line (Ll) at the point of intersection with the leading edge and with the trailing edge and a respective straight line perpendicular to the plane (XY) passing through the corresponding points of intersection and also being characterised in that the angles (BLE, BTE) of the profiles (13 - 19) have the values indicated in the following table: Profile Radial extension (%) Radius (mm) BLE (degrees) BTE (degrees) 13 0 55 78.47 55.15 14 17.9 72.15 81.38 49.31 15 44.5 97.75 82.93 48.46 WO 2006/1)06043 PCT/IB2005/001898 13 16 71.2 123.35 83.53 51.96 17 81.5 133.27 83.99 53.96 18 97.9 148.95 84.82 54.96 19 100 151 85.28 54.85 15. The axial fan (1) according to any of the foregoing claims, characterised in that the blade (4) consists of at least several aerodynamic profiles (13 - 19), relative to respective sections at various intervals along the radial extension of a blade (4) , each profile (13 - 19) being formed by a centre line (LI) which is continuous and free of points of inflection or cusps and also being characterised in that the profiles (13 - 19) have a thickness S-MAX equal to 1.6% of the tip radius Rmax. 16. The axial fan (1) according to claim 15, characterised in that the profiles (13 - 19) have a thickness which is arranged symmetrically relative to the centre line (LI) and a thickness trend that is initially increasing, a maximum value S-MAX at around 40% of the length of the centre line (LI) , and then gradually decreasing as far as the trailing edge 8 and also being characterised in that the thickness trend is defined by the following table: Extension Radius Profile Dimensionless thickness relative to S-MAX {%) (mm) 0% LI 20% LI 40% LI 60% Ll 80% Ll 100% Ll 13 0 55 0 . 681633 0. 967347 1 0 808163 0 534694 0. 2 14 17.9 72.15 0 .681633 0 967347 1 0 808163 0 534694 0. 2 15 44.5 97.75 0 . 681633 0 967347 1 0 808163 0 534694 0 2 16 71.2 123.35 0 .681633 0 967347 1 0 808163 0 534694 0 2 17 81.5 133.27 0 .681633 0 967347 1 0 808163 0 534694 0 2 18 97.9 148.95 0 .681633 0 967347 1 0 808163 0 534694 0 2 19 100 151 0 . 681633 0 967347 1 0 808163 0 534694 0 2 17. The axial fan (1) according to any of the claims from 1 to 14, characterised in that the blade (4) consists of at least several aerodynamic profiles (13 - 19), relative to respective sections at various intervals along the radial extension of a blade (4), each profile (13 - 19) being formed by a centre line (Ll) which is continuous and free of points of inflection or cusps and WO 2006/006043 PCT/1B2005/001898 14 also being characterised in that the profiles (13 - 19) have a thickness S-MAX equal to 2.6% of the tip radius Rmax. 18. The axial fan (1) according to claim 17, characterised in that the profiles (13 - 19) have a thickness that is arranged symmetrically relative to the centre line (Ll) and a thickness trend that is initially increasing, a maximum value S-MAX at around 30% of the length of the centre line (Ll) , and then gradually decreasing as far as the trailing edge 8 and also being characterised in that the thickness trend is defined in the following table: Profile Extension Radius Dimensionless thickness relative to S-MAX (%) (mm) 0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll 13 0 55 0.42 0.9486 0.9667 0.75 0.46 0.125 14 17.9 72.15 0.42 0.9486 0.9667 0.75 0.46 0.125 15 44.5 97.75 0.42 0.9486 0.9667 0.75 0.46 0.125 16 71.2 123.35 0.42 0.9486 0.9667 0. 75 0.46 0.125 17 84.5 136.15 0.42 0.9486 0.9667 0. 75 0.46 0.125 18 97.9 148.95 0.42 0.9486 0.9667 0. 75 0.46 0.125 19 100 151 0.42 0.9486 0.9667 0.75 0.46 0.125 An axial fan (1) rotating in a plane (XY) about an axis (2) comprises a central hub (3), a plurality of blades (4), which have a root (5) and a tip (6), the blades (4) being delimited by a convex, leading edge (7) and by a concave trailing edge (8), their projections in the fan rotation plane each being formed by circular arc segments; the blades (4) are made from sections with aerodynamic profiles, each with decreasing length and more curved from the perimeter to the hub.

Full Text

WO 2006/006043 PCT/IB2005/001898
1
AXIAL FAN Description
Technical Field
The present invention relates to an axial fan with blades angled in the fan plane of rotation.
The fan according to the present invention may be used in various applications, for example, to move air through a heat exchanger, or radiator, of a cooling system for the engine of a motor vehicle or the like; or to move air through the heat exchanger of the heating system and/or through the evaporator of the air conditioning system of the interior of a motor vehicle. Moreover, the fan according to the present invention may be used to move air in fixed air conditioning or heating systems for houses.
Background Art
Fans of this type must satisfy various requirements, including: low noise level, high efficiency, compactness, capacity to achieve good pressure and flow rate values.
In particular, achieving good general performance while keeping noise levels down requires careful design of the blades and the profiles of which they consist.
A fan of this type is known from United States patent US-6 241 474, which describes a low noise fan with blades whose angle or pitch decreases gradually from the hub to the tip over a predetermined extension of the radius, then their angle increases again towards the tip. The blades are connected to one another by an external ring.
Disclosure of the Invention
One aim of the present invention is to provide a fan which has good general performance with a low noise level.

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According to one aspect of the present invention, an axial fan as specified in claim 1 is presented.
The dependent claims refer to preferred and advantageous embodiments of the invention.
Brief Description of the Drawings
The invention is described in more detail below with reference to the accompanying drawings, which illustrate a preferred, non-limiting embodiment, in which:
Figure 1 is a front view of the fan in accordance with the present invention;
Figure 2 is a schematic front view of a blade of the fan illustrated in the previous figure;
Figure 3 is a cross-section of several profiles at various fan diameters; and
Figure 4 is a cross-section of a profile and the respective geometric characteristics.
Detailed description of the Preferred Embodiments of the Invention
With reference to the accompanying drawings, the fan 1 rotates about an axis 2 and comprises a central hub 3 to which a plurality of blades 4 are connected, the blades being curved in the fan 1 plane of rotation XY.
The blades 4 have a root 5, a tip 6 and are delimited by a convex leading edge 7 and a concave trailing edge 8.
For the best results in terms of efficiency, flow rate and air pressure, the fan 1 rotates with a direction of rotation V, illustrated in Figures 1 and 4, so that the tip 6 of each blade 4 encounters the air flow after the root 5.
Maintaining the direction of rotation V, the fan 1 can be produced as a blowing fan or as a suction fan, by suitably modifying and adapting the profiles of the blades. The following description refers to a blowing fan by way of example.
Figure 2 illustrates an example of the geometric characteristics of a blade 4: the leading edge 7 is delimited by two circular arc segments 9, 10, and the trailing edge 8 is delimited by one circular arc segment 11. In the leading edge 7, a

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radius labelled Rl is the point of change from one circular arc segment to the other circular arc segment.
According to the example in Figure 2, the general dimensions of the projection of a blade 4 in the plane XY are summarised in table 1:
Table 1 - dimensions of a blade 4.
Radius of internal segment (mm) Radius of change (mm) Radius of external segment (mm)
Leading edge (Ref. 7) 133.57 (Ref. 9) 97.75 (Ref. Rl) 83.23 (Ref. 10)
Radius (mm)
Trailing edge (Ref. 8) S7.25 (Ref. 11)
The general geometric characteristics of the blade 4 are defined relative to a hub with 110 mm diameter, that is to say, the blade 4 has a minimum radius Rmin = 55 mm at the root 5, and a 3 02 mm external diameter, giving it a maximum radius Rmax = 151 mm at the tip 6, meaning that the blade 4 has a 96 mm radial extension.
As illustrated in the accompanying drawings, the outside of the fan may be fitted with a connecting ring 12 which may be several millimetres thick, meaning that the fan 1 in the example embodiment provided has an overall diameter of approximately 310 mm.
As is known, one of the functions of the connecting ring is to stiffen the outer part of the blades 4 so as to promote maintenance of the angles of angles of incidence and to improve the aerodynamic performance of the outer profiles of the blades, reducing the formation of vortices at the tip 6 of the blades 4.
However, it should be noticed that good results were also achieved using a fan made according to the present invention without the connecting ring.
Considering that the blade 4 has a minimum radius Rmin = 55 mm and a maximum radius Rmax = 151 mm, the leading edge 7 has a radius Rl, where the change in the circular arc occurs, corresponding to around 44% of the radial extension of the leading edge 7, an extension which, as already indicated, is 96 mm.
The part 9 of the leading edge 7 closest to the root 5 consists of a circular arc with a radius equal to around 88% of the

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radius Rmax, and the part 10 of the leading edge 7 closest to the
tip 6 consists of a circular arc segment with a radius equal to
around 55% of the radius Rmax of the blade 4.
As regards the trailing edge 8, the circular arc segment 11
has a radius equal to around 44.5% of the radius Rmax of the blade
4.
The dimensions in percentages are summarised in table 2: Table 2 - blade 4 dimensions in percentage form.
Internal segment radius (% ofRmax) Change radius (% of blade extension = Rmax-Rmin) External segmentradius (% of Rmax)
Leading edge (Ref. 7) 88 (Ref. 9) 44 (Ref. Rl) 55 (Ref. 10)
Radius (% of Rmax)
Trailing edge (Ref. 8) 44.5 (Ref. 11)
Satisfactory results in terms of flow rate, pressure and noise were achieved even with values around these percentage dimensions. In particular, variations of 10% more or less on the above-mentioned dimensions are possible.
The percentage ranges relative to the dimensions are summarised in table 3:
Table 3 - Blade 4 edges percentage ranges.
Internal segment radius {% of Rmax) Change radius {% of blade extension = % of Rmax-Rmin) External segment radius {% of Rmax)
Leading edge (Ref. 7) 79 - 97 (Ref. 9) 40 - 48.5 (Ref. Rl) 49.5 - 60.5 (Ref. 10)
Radius (.% Rmax)
Trailing edge (Ref. 8) 40 - 49 (Ref. 11)
For the leading edge 7, in the circular arc segment change zone, there may be a suitable fillet so that the edge 7 is continuous and free of cusps.
As regards the width or angular extension of the blades, again with reference to Figure 2, the projection of the blade 4 in the plane XY has an amplitude, at the root 5, represented by an angle Bl of around 60 degrees and an amplitude, at the tip 6, represented

WO 2006/006043 PCT/IB2005/001898
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by an angle B2 of around 2 6 degrees.
Again, satisfactory results were achieved in terms of flow rate, pressure and noise with values of angles Bl, B2 around these values. In particular, variations of 10% more or less than the angles indicated are possible. The angle Bl may vary from 54 to 66 degrees, whilst the angle B2 may vary from 23 to 29 degrees.
In general, it must also be considered that, due to the plastic material used to make fans, variations in all of the dimensions and angles of 5% more or less must all be considered within the values indicated. Considering the respective bisecting lines and following the fan 1 direction of rotation V, the tip 6 is further back than the root 5 by an angle B3 of around 26 degrees.
Other angles characteristic of the blade 4 are angles B4, B5, B6, B7 (Figure 2) formed by the respective tangents to the two edges 7, 8 and by the respective lines passing through points M, N, S, T: the angles B4 and B5 are respectively 28 and 54 degrees and the angles B6, B7 are respectively 28 and 45 degrees.
There may be between three and seven blades 4 and, according to a preferred embodiment, there are five blades 4 and they are separated by equal angles.
Each blade 4 consists of a set of aerodynamic profiles which gradually join up starting from the root 5 towards the tip 6.
Figure 3 illustrates seven profiles 13 - 19, relative to respective sections at various intervals along the radial extension of a blade 4.
The profiles 13 - 19 are also formed by the geometric characteristics of which an example is provided in Figure 4 for one of the profiles.
As illustrated in Figure 4, each profile 13 - 19 is formed by a continuous centre line Ll without points of inflection or cusps and by a chord L2.
Each profile 13 - 19 is also formed by two angles BLE, BTE of incidence with the leading edge and with the trailing edge, said angles formed by the respective tangents to the centre line Ll at the point of intersection with the leading edge and with the trailing edge and a respective straight line perpendicular to the plane XY passing through the corresponding points of intersection.

WO 2006/006043 PCT/IB2005/001898
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With reference to the seven profiles 13 - 19, table 4 below indicates the angles of the leading edge BLE and of the trailing edge BTE, the length of the centre line LI and the chord L2 of the profiles of a blade 4.
Table 4 - Radial position, angles of leading and trailing edges, length of centre line and chord of the profiles of a blade 4.
Profile Radial extension (%> Radius (mm) BLE (degrees) BTE (degrees) LI (centre line mm) L2 (chord mm)
13 0 55 78.47 55.15 64.12 63.66
14 17.9 72.15 81.38 49.31 65.37 64.53
15 44.5 97.75 82.93 48.46 69.40 68.30
16 71.2 123.35 83.53 51.96 73.28 73.31
17 81.5 133.27 83.99 53.96 73.95 73.04
18 97.9 148.95 84.82 54.96 72.63 71.64
19 100 151 85.28 54.85 72.18 71.14
It should be noticed that the thickness of each profile 13 -19, according to a typical trend of wing-shaped profiles, initially increases, reaching a maximum value S-MAX at around 40% of the length of the centre line Ll, then it gradually decreases as far as the trailing edge 8.
In percentages, the thickness S-MAX is around 1.6% of the radius Rmax; the thickness of the profiles is distributed symmetrically relative to the centre line Ll.
The positions of the profiles 13 - 19 relative to the radial extension of a blade 4 and the relative values for the thickness, trend according to their position with respect to the centre line Ll are summarised in table 5.
Table 5 - Radial position and thickness trend of blade 4 profiles.
Profile Extension (%) Radius (mm) Thickness
S-MAX (mm) dimensionless relative to S-MAX
0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll
13 0 55 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2
14 17.9 72.15 2.45 0.681633 0.967347 2 0.808163 0.534694 0.2
15 44.5 97.75 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2
16 71.2 123.35 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2
17 81.5 133.27 2.45 0.681633 0.967347 1 0.808163 0.534694 0.2
18 97.9 148.95 2.45 0.5 31633 0.967347 1 0.808163 0.534694 0.2
19 100 151 2.45 0.681633 0.967347 1 0.808163 0.53461 I 0.2

WO 2006/006043 PCT/IB2005/001898
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Table 6 below summarises the actual mm values of the trend of thicknesses according to their position with respect to the centre line Ll for each profile 13 - 19 with reference to the embodiment illustrated.
Table 6 - Thickness trend in mm of blade 4 profiles 13 - 19.
Profile Thickness (mm)
0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll
13 1.67 2.37 2.45 1.98 1.31 0.49
14 1.67 2.37 2.45 1.98 1.31 0.49
15 1.67 2.37 2.45 1.98 1.31 0.49
16 1.67 2.37 2.45 1.98 1.31 0.49
17 1.67 2.37 2.45 1.98 1.31 0.49
18 1.67 2.37 2.45 1.98 1.31 0.49
19 1.67 2.37 2.45 1.98 1.31 0.49
The profiles 13 - 19 are preferably delimited with a semicircular fillet, on the leading edge 7 side, and with a truncation created using a segment of a straight line on the trailing edge 8 side.
In an alternative embodiment, good general performance was achieved in terms of the noise, flow rate and pressure supplied by the fan disclosed even with thicker profiles. According to said alternative embodiment, the positions of the profiles 13 - 19 relative to the radial extension of a blade and the relative thickness trend values according to their position with respect to the centre line Ll are summarised in table 7.
It should also be noticed that, in this embodiment, the thickness S-MAX is reached at 30% of the length of the centre line Ll.
Table profiles.
7 - Radial position and thickness trend of blade 4

Profile Extension (%) Radius (mm) Thickness
S-MAX (mm) dimensionless relative to S-MAX
0% Ll 20% Ll 40% Ll 60%Ll 80% Ll 100% Ll
13 0 55 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125
14 17.9 72.15 3.98 0.42 0.9486 0.9667 0.75 0.46 0.125
15 44.5 97.75 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125
16 71.2 123.35 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125
17 84.5 136.15 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125
18 97.9 148.95 3.98 0.42 0.9486 0.9667 0.75 . 0.46 0.125
19 100 151 3.98 0.42 0.9486 0.9667 0. 75 0.46 0.125
Table 8 below summarises the actual mm values of the trend of

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thicknesses according to their position with respect to the centre
line LI for each profile 13 - 19 relative to the embodiment
illustrated in the accompanying drawings.
Table 8 - Thickness trend in mm of blade 4 profiles 13 - 19.

Profile Thickness (mm)
0% LI 20% LI 40% LI 60% LI 80% LI 100% LI
13 1.67 3.77 3.85 2.99 1.83 0.49
14 1.67 3.77 3.85 2.99 1.83 0.49
15 1.67 3.77 3.85 2.99 1.83 0.49
16 1.67 3.77 3.85 2.99 1.83 0.49
17 1.67 3.77 3.85 2.99 1.83 0.49
18 1.67 3.77 3.85 2.99 1.83 0.49
19 1.67 3.77 3.85 2.99 1.83 0.49
As may be seen, in both embodiments, the profiles 13 - 19 have the same thickness in the corresponding positions (0% of LI, 20% of LI, ..., 80% of LI, etc.) along the extension of the centre line Ll.
The first embodiment with the thinner profiles has advantages in terms of lightness, cost and ease of moulding.
The second embodiment with the thicker profiles has advantages in terms of aerodynamic efficiency, since the thicker profiles have better performance to prevent stalling.
The invention described may be subject to modifications and variations without thereby departing from the scope of the inventive concept described in the claims herein.

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LIST OF REFERENCE CHARACTERS
Reference Description
1 AXIAL FAN
2 AXIS OF ROTATION
3 CENTRAL HUB
4 FAN 1 BLADE
5 BLADE 4 ROOT
6 BLADE 4 TIP
7 CONCAVE LEADING EDGE
8 CONVEX TRAILING EDGE
9 CIRCULAR ARC SEGMENT (INTERNAL)
10 CIRCULAR ARC SEGMENT (EXTERNAL)
11 CIRCULAR ARC SEGMENT
12 CONNECTING RING
13-19 AERODYNAMIC PROFILES
XY ROTATION PLANE
V DIRECTION OF ROTATION
Rl RADIUS OF CHANGE BETWEEN SEGMENTS 9 AND 10
XY PROJECTION IN THE PLANE
Bl - B7 BLADE 4 CHARACTERISTIC ANGLES
M, N, S, T BLADE 4 CHARACTERISTIC POINTS
LI CENTRE LINE
L2 CHORD
BLE LEADING EDGE ANGLES OP INCIDENCE
BTE TRAILING EDGE ANGLES OF INCIDENCE

WO 2006/006043 PCT/JB2G05/001898
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Claims
1. An axial fan (1), rotating in a direction (V) in a plane
(XY) about an axis (2), comprising a central hub (3) with a radius
(Rmin) , a plurality of blades (4) each, having a root (5) , a tip
(6) which extends to a tip radius (Rmax) , the blades (4) being
delimited by a convex leading edge (7) and a concave trailing edge
(8), the axial fan being characterised in that the leading edge
(7) comprises a first circular arc segment (9) close to the root
(5) with a radius of between 79% and 97% of the tip radius (Rmax)
and a second circular arc segment (10) close to the tip (6) with a
radius of between 49.5% and 60.5% of the tip radius (Rmax), and a
radius at the change between the two circular arc segments (9, 10)
of between 40% and 48.5% of the extension (Rmax - Rmin) of the
blade (4).
2. The axial fan (1) according to claim 1, characterised in
that the trailing edge (8) comprises a circular arc segment (11)
with a radius of between 40% and 49% of the tip radius (Rmax).
3. The axial fan (1) according to claim 1 or 2, characterised
in that the leading edge (7) comprises a first circular arc
segment (9) close to the root (5) with a radius which is 88% of
the tip radius (Rmax) and a second circular arc segment (10) close
to the tip (6) with a radius which is 55% of the tip radius
(Rmax) , and a radius at the change between the two circular arc
segments (9, 10) which is 44% of the extension (Rmax - Rmin) of
the blade (4).
4. The axial fan (1) according to any of the foregoing claims,
characterised in that the trailing edge (8) comprises a circular
arc segment (11) with a radius which is 44.5% of the tip radius
(Rmax) .
5. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane

WO 2006/006043 PCT/IB2005/001898
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(XY) has an amplitude, at the root (5) , with an angle (Bl) of between 54 and 66 degrees.
6. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) has an amplitude, at the tip (6) , with an angle (B2) of
between 23 and 29 degrees.
7. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) has an amplitude, at the root (5) , with an angle (Bl) of
around SO degrees.
8. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) has an amplitude, at the tip (6), with an angle (B2) of around
26 degrees.
9. The axial fan (1) according to any of the foregoing claims,
characterised in that, considering the projection of the blade (4)
in the plane (XY) and fan (1) direction of rotation (V) , the tip
(6) is further back than the root (5) by an angle (B3) of around 26
degrees.

10. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) forms a point (M) of intersection between the leading edge (7)
and the hub (3) with an angle (B4) of 28 degrees, the angle (B4)
being formed by the respective tangent to the leading edge (7) at
the point (M) and by a respective line from the axis (2) of the fan
(1) passing through the point (M).
11. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) forms a point (N) of intersection between the leading edge (7)
and the tip (6) with an angle (B5) of 54 degrees, the angle (B5)
being formed by the respective tangent to the leading edge (7) at

WO 20(16/006043 PCT/LB2005/001898
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the point (N) and by a respective line from the axis (2) of the fan (1) passing through the point (N).
12. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) forms a point (S) of intersection between the trailing edge
(8) and the hub (3) with an angle (B6) of 28 degrees, the angle
(B6) being formed by the respective tangent to the trailing edge
(8) at the point (S) and by a respective line from the axis (2) of
the fan (1) passing through the point (S).
13. The axial fan (1) according to any of the foregoing claims,
characterised in that the projection of the blade (4) in the plane
(XY) forms a point (T) of intersection between the trailing edge
(8) and the tip (6) with an angle (B7) of 45 degrees, the angle
(8) at the point (T) and by a respective line from the axis (2) of
the fan (1) passing through the point (T).
14. The axial fan (1) according to any of the foregoing claims, characterised in that the blade (4) consists of at least several aerodynamic profiles (13 - 19) relative to respective sections at various intervals along the radial extension of a blade (4), each profile (13 - 19) being formed by a centre line (LI) which is continuous and without points of inflection or cusps and by two angles (BLE, BTE) of incidence with the leading edge and the trailing edge, the angles being formed by the respective tangents to the centre line (Ll) at the point of intersection with the leading edge and with the trailing edge and a respective straight line perpendicular to the plane (XY) passing through the corresponding points of intersection and also being characterised in that the angles (BLE, BTE) of the profiles (13 - 19) have the values indicated in the following table:
Profile Radial extension (%) Radius (mm) BLE (degrees) BTE (degrees)
13 0 55 78.47 55.15
14 17.9 72.15 81.38 49.31
15 44.5 97.75 82.93 48.46

WO 2006/1)06043 PCT/IB2005/001898
13

16 71.2 123.35 83.53 51.96
17 81.5 133.27 83.99 53.96
18 97.9 148.95 84.82 54.96
19 100 151 85.28 54.85
15. The axial fan (1) according to any of the foregoing claims,
characterised in that the blade (4) consists of at least several
aerodynamic profiles (13 - 19), relative to respective sections at
various intervals along the radial extension of a blade (4) , each
profile (13 - 19) being formed by a centre line (LI) which is
continuous and free of points of inflection or cusps and also being
characterised in that the profiles (13 - 19) have a thickness S-MAX
equal to 1.6% of the tip radius Rmax.
16. The axial fan (1) according to claim 15, characterised in
that the profiles (13 - 19) have a thickness which is arranged
symmetrically relative to the centre line (LI) and a thickness
trend that is initially increasing, a maximum value S-MAX at around
40% of the length of the centre line (LI) , and then gradually
decreasing as far as the trailing edge 8 and also being
characterised in that the thickness trend is defined by the
following table:
Extension Radius
Profile Dimensionless thickness relative to S-MAX
{%) (mm) 0% LI 20% LI 40% LI 60% Ll 80% Ll 100% Ll
13 0 55 0 . 681633 0. 967347 1 0 808163 0 534694 0. 2
14 17.9 72.15 0 .681633 0 967347 1 0 808163 0 534694 0. 2
15 44.5 97.75 0 . 681633 0 967347 1 0 808163 0 534694 0 2
16 71.2 123.35 0 .681633 0 967347 1 0 808163 0 534694 0 2
17 81.5 133.27 0 .681633 0 967347 1 0 808163 0 534694 0 2
18 97.9 148.95 0 .681633 0 967347 1 0 808163 0 534694 0 2
19 100 151 0 . 681633 0 967347 1 0 808163 0 534694 0 2
17. The axial fan (1) according to any of the claims from 1 to 14, characterised in that the blade (4) consists of at least several aerodynamic profiles (13 - 19), relative to respective sections at various intervals along the radial extension of a blade (4), each profile (13 - 19) being formed by a centre line (Ll) which is continuous and free of points of inflection or cusps and

WO 2006/006043 PCT/1B2005/001898
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also being characterised in that the profiles (13 - 19) have a thickness S-MAX equal to 2.6% of the tip radius Rmax.
18. The axial fan (1) according to claim 17, characterised in that the profiles (13 - 19) have a thickness that is arranged symmetrically relative to the centre line (Ll) and a thickness trend that is initially increasing, a maximum value S-MAX at around 30% of the length of the centre line (Ll) , and then gradually decreasing as far as the trailing edge 8 and also being characterised in that the thickness trend is defined in the following table:

Profile Extension Radius
Dimensionless thickness relative to S-MAX
(%) (mm) 0% Ll 20% Ll 40% Ll 60% Ll 80% Ll 100% Ll
13 0 55 0.42 0.9486 0.9667 0.75 0.46 0.125
14 17.9 72.15 0.42 0.9486 0.9667 0.75 0.46 0.125
15 44.5 97.75 0.42 0.9486 0.9667 0.75 0.46 0.125
16 71.2 123.35 0.42 0.9486 0.9667 0. 75 0.46 0.125
17 84.5 136.15 0.42 0.9486 0.9667 0. 75 0.46 0.125
18 97.9 148.95 0.42 0.9486 0.9667 0. 75 0.46 0.125
19 100 151 0.42 0.9486 0.9667 0.75 0.46 0.125

An axial fan (1) rotating in a plane (XY) about an axis (2) comprises a central hub (3), a plurality of blades (4), which have a root (5) and a tip (6), the blades (4) being delimited by a convex, leading edge (7) and by a concave trailing edge (8), their projections in the fan rotation plane each being formed by circular arc segments; the blades (4) are made from sections with aerodynamic profiles, each with decreasing length and more curved from the perimeter to the hub.

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Patent Number

261189

Indian Patent Application Number

3911/KOLNP/2006

PG Journal Number

24/2014

Publication Date

13-Jun-2014

Grant Date

10-Jun-2014

Date of Filing

26-Dec-2006

Name of Patentee

SPAL AUTOMOTIVE S.r.L

Applicant Address

VIA PER CARPI ,26/B I-42015 CORREGGIO (REGGIO EMILIA)

Inventors:

#	Inventor's Name	Inventor's Address
1	SPAGGIARI, ALESSANDRO	VIA LEONARDO DA VINCI,8I-42015 CORREGGIO (REGGIO EMILIA)

PCT International Classification Number

F04D29/38; F04D29/38

PCT International Application Number

PCT/IB2005/001898

PCT International Filing date

2005-07-05

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	BO2004A000417	2004-07-06	Italy