WO2015090354A1

WO2015090354A1 - Rotor with tinted blades

Info

Publication number: WO2015090354A1
Application number: PCT/EP2013/076753
Authority: WO
Inventors: Serge BERNICAT; Christian BARE-GUILLET
Original assignee: Bernicat Serge; Bare-Guillet Christian
Priority date: 2013-12-16
Filing date: 2013-12-16
Publication date: 2015-06-25

Abstract

Bladed rotor, in which the blades (3) have specific tinted zones (4) which are situated on the tip parts thereof, at least on one side, and which follow the same path as the rotor turns. The specific zones are tinted with a first and a second tint from the visible spectrum, following on circumferentially from one another. The wavelength of the first tint (Tc) is comprised between 550 and 650 nanometres. The wavelength of the second tint (Tn) is either equal to or less than the wavelength of the first tint chosen, minus 145 nanometres or equal to or greater than the wavelength of the first tint chosen, plus 145 nanometres, or equal to a wavelength of one of the extreme portions of the visible spectrum or a black if the calculated value lies outside of the visible spectrum.

Description

Rotor with tinted blades

The present invention relates to the field of devices with paddle rotors, such as helicopters or fans.

Such blades are dangerous because, when the rotor is rotating, the path they run or disk rotor is difficult to see.

In the case of a moving aircraft such as a helicopter, it is very difficult for the pilot to see the blade tips rotating, so that if he is to approach an obstacle such as a rock wall during rescue in the mountains, a wall of a building, a pylon or a tree, the blades may hit the obstacle and cause an accident.

In the case of a generally immobile apparatus such as a domestic or industrial ventilator or a ventilator associated with an engine of a motor vehicle, there is the risk that a person approaching in particular his hand, his clothing or an object and rotating blades, by necessity or inadvertently, do not give a good account of the path or rotor disk traversed by these blades and causes an accident.

The present invention aims to improve the visibility of the ends of the blades in rotation of a blade rotor.

It is first of all specified that the visible light, also called visible spectrum or optical spectrum is the part of the electromagnetic spectrum which is visible for the human eye. There is no exact limit to the visible spectrum. Generally, the response of the eye is considered to cover wavelengths of 380 nm to 780 nm, although a wavelength range of 400 nm to 700 nm is more common. According to one embodiment of the invention, the blades have tinted specific areas which are located on their end portions, at least on the same side, and which run in the same path during rotation of the rotor; adding the surfaces of said specific areas determines a total area; the total surface is divided into a first and a second total surface portion disposed circumferentially to one another and tinted respectively by first and second shades of the light or visible electromagnetic spectrum; the first hue is selected from hues whose wavelength is in a range of 550 to 650 nanometers; and the second hue is selected from hues whose wavelength is either equal to or less than the selected wavelength of the first hue at which 145 nanometers are subtracted, or equal to or greater than the wavelength of the hue. first hue chosen to which 145 nanometers is added, equal to a wavelength of one of the extreme parts of the visible spectrum or a black in the case where the calculated value is outside the visible spectrum.

Thus, the first hue is chosen from the so-called "light or bright" colors and the second hue is chosen from the so-called "dark, dark or black" colors, relative to the first hue.

It follows that, during the rotation of the rotor with blades, the visibility of the crown, on which is visible the trail of hues, resulting from the path traveled by said specific areas tinted or corresponding to a substantially annular portion of the resulting rotor disk said tinted specific areas are increased, this ring being able to have a variable thickness if the blades undergo fluctuations in the direction of the rotor axis with blades, as in the case where the present invention would be applied to the blades of a rotor with blades of a helicopter.

Different embodiments of the present invention are possible. The first surface portion may have a value that is at most equal to 50% and at least 20% of said total area.

The tinted areas may extend to the ends of the blades.

The tinted areas may extend over the entire width of the blades.

Each blade may carry only one of said shades.

The blades may have tinted sub-zones adjacent to said tinted areas and located radially inward, these sub-zones bearing dark hues.

Said zones may have, in the radial direction, lengths between 10% and 20% of the length of the blades.

The wavelength of the first hue can be selected in the range of 575 to 595 nanometers.

Various blade rotors having specific areas tinted according to the present invention will now be described by way of non-limiting examples, illustrated by the drawing in which:

- Figure 1 shows a rotor with two blades;

- Figure 2 shows a rotor with three blades;

- Figure 3 shows a rotor with four blades;

- Figure 4 shows a rotor with five blades;

- Figure 5 shows a rotor with six blades;

- Figure 6 shows a rotor with seven blades;

FIG. 7 represents a first wavelength diagram of the visible spectrum; and

- Figure 8 shows a second wavelength diagram of the visible spectrum.

In Figure 1 is shown a rotor 1 which comprises a rotary shaft 2 provided with two identical blades 3 extending radially outwardly and diametrically opposite.

On the same side, the blades 3 have specific areas 4, identical in shape and surface, which are situated on their end parts and which run in the same path during the rotation of the rotor 1. According to the example shown, the specific areas 4 extend circumferentially substantially along the width of the blades 3 and, radially in the direction of the direction of the blades 3, from a location at a distance from the ends to the ends of the blades 3.

According to an alternative embodiment, the other faces of the blades 2 could also have specific areas 4.

According to another variant embodiment, the specific zones 4 may extend over the entire periphery of the blades 3.

The specific zones 4 may have lengths of between 10% and 20% of the length of the blades 3.

On their specific areas 4, one of the blades 3 carries a first shade Tc and the other a second shade Tn.

As a result, the area covered by the hue Tc is equal to the area covered by the hue Tn, so that the hue Tc _. covers 50% of the addition of the surfaces of the specific zones 4 of the two blades 3.

FIG. 2 shows a rotor 5 different from the rotor 1 in that it comprises three angularly distributed blades 3 identically having specific zones 4. This time, on their specific zones 4, one of the three blades 3 carries a T hue while the other two have a tint Tn.

As a result, the area covered by the Tc hue is equal to one third of the addition of the surfaces of the specific zones 4 of the three blades 3.

In Figure 3 is shown a rotor 6 different from the rotor 1 in that it comprises four angularly distributed blades 3. This time, on their specific areas 4, one of the four blades have a Tc hue while the other three have a tint Tn.

As a result, the area covered by the tint Tc is equal to a quarter of the addition of the surfaces of the specific zones 4 of the four blades 3.

According to an alternative embodiment, two blades adj acentes or circumferentially succeeding could carry a tint Tç while the other two blades adj acentes or succeeding circumferentially would then wear a Tn tint.

In Figure 4 is shown a rotor 7 different from the rotor 1 in that it comprises five blades 3 angularly distributed. This time, on their specific areas 4, two blades adj acentes or which succeed each circumferentially carry a tint Tc _. while the other three blades adj acentes or which succeed each circumferentially carry a tint Tn.

As a result, the area covered by the color Tc is equal to three fifths of the addition of the surfaces of the specific zones 4 of the five blades 3.

According to an alternative embodiment, on their specific areas 4, one of the blades could carry a Tc tint while the other four blades would then wear a tint Tn.

In Figure 5 is shown a rotor 6 different from the rotor 8 in that it comprises six blades 3 angularly distributed. This time, on their specific zones 4, two adjacent or circumferentially succeeding blades carry a tint while the other four adjacent or circumferentially succeeding blades carry a tint Tn.

As a result, the area covered by the Tc hue is equal to one third of the addition of the surfaces of the specific zones 4 of the six blades 3.

According to an alternative embodiment, three blades that are adjacent to each other or that circumferentially succeed each other could carry a Tc shade _. while the other three blades adj acentes or which succeed one another circumferentially would carry a tint Tn.

In Figure 6 is shown a rotor 9 different from the rotor 1 in that it comprises seven blades 3 angularly distributed. This time, on their specific areas 4, three blades adj acentes or circumferentially succeeding wear a Tç tint while the other four blades adjacent or succeeding circumferentially carry a tint Tn. As a result, the area covered by the color Te is equal to three seventh of the addition of the surfaces of the specific zones 4 of the seven blades 3.

According to an alternative embodiment, two blades adj acentes or circumferentially succeeding could carry a tint Tc _. while the other five blades adj acentes or which succeed one another circumferentially would carry a shade Tn.

It follows from the foregoing that, in general, on the circumference of a rotor, irrespective of the number of blades, the colors Tc and Tn are not alternately arranged, but one as a result of the other.

Also generally, the total area resulting from the addition of the surfaces of the specific zones 4 of the rotor blades 3 is divided into a first and a second total surface portion disposed circumferentially in succession to each other. and tinted respectively by the first shade Tc _. and the second hue Tn, the first surface portion covered with the hue T having a value at most equal to 50% and at least equal to 20% of said total area.

According to an alternative embodiment, while having the colors

Te and Tn one after the other on a circumference of a rotor, at least one of the blades could carry both Tc and Tn shades.

Referring to Figures 7 and 8, we will now define the possible choices of shades Tc and Tn.

The Tc and Tn shades are chosen from the hues of the light or visible electromagnetic spectrum to which the human eye is sensitive. The visible spectrum includes wavelengths between 380 and 780 nanometers, but generally ranges from 400 to 700 nanometers.

The Tc hue is clear and is chosen from hues whose wavelength is between 550 nanometers and 650 nanometers, preferably from hues whose wavelength is between 575 and 595 nanometers.

The Tn hue is rather a dark hue or a black. According to the variant embodiment illustrated in FIG. 7, having chosen a shade Te, one subtracts 145 nanometers from the value of the wavelength e of this shade Tc _. and we obtain a value of a wavelength nb. The tint Tn is then chosen among hues whose wavelength λη is equal to or less than this calculated wavelength Tnb.

According to the other variant embodiment illustrated in FIG. 8, having chosen a color Te, we subtract 145 nanometers from the value of the wavelength λ 0 of this color Tc_ and we obtain a value of a wavelength ληΐι . The tint Tn is then chosen among the shades whose wavelength is equal to or greater than this calculated wavelength ληΐι.

Nevertheless, it is possible that the calculated wavelength λnb or ληΐι is outside the visible spectrum. In this case, one chooses a tint Te whose wavelength λη is located in one of the extreme parts of the visible spectrum or a black.

When rotating any of the rotor blades described above, the shades T _ and Tn form visible streaks on a crown resulting from the path traveled by the specific zones 4 of the blades 3, that is to say on an outer ring of the rotor disc swept by the blades 3, so that the visibility of this ring swept by the end portions of the blades 3 is increased.

The arrangements described above may be applied to paddle rotors such as those of helicopters or equipment such as fans.

In the case of a helicopter, the specific areas tinted 4 of the rotor blades are provided on the lower faces of the blades 3, so that the pilot, installed inside the cockpit of the helicopter and seeing, according to a strongly inclined angle, the lower faces of the blades 3 of the rotor, can better see the crown swept by the end portions of the blades 3.

In the case of a domestic or industrial fan, the tinted specific areas 4 may be provided on both sides or all around the end portions of the blades of this fan, so that the end portions of the blades 3 are more visible by anyone approaching them.

The present invention is not limited to the examples described above. Many other embodiments are possible, without departing from the scope of the invention.

Claims

1. Rotor blade, characterized by the fact:

the blades (3) have specific areas (4) which are tinted on their end parts, at least on the same side, and which run in the same path when the rotor rotates, that the addition of the surfaces of said specific areas determines a total area,

the total area is divided into a first and a second total surface portion disposed circumferentially to each other and respectively tinted with a first and a second shade of the light or visible electromagnetic spectrum,

that the first hue (Te) is chosen from hues whose wavelength is in a range between 550 and 650 nanometers,

and that the second hue (Tn) is selected from hues whose wavelength is either equal to or less than the chosen wavelength of the first hue at which 145 nanometers are cut off, or equal to or greater than the length of the hue. wave of the first selected hue to which is added 145 nanometers, equal to a wavelength of one of the extreme parts of the visible spectrum or a black in the case where the calculated value is outside the visible spectrum.

2. Rotor according to claim 1, wherein the first surface portion has a value that is at most equal to 50% and at least equal to 20% of said total area.

3. Rotor according to any one of the preceding claims, wherein the tinted areas extend to the ends of the blades.

4. Rotor according to any one of the preceding claims, wherein the tinted areas extend over the entire width of the blades.

5. Rotor according to any one of the preceding claims, wherein each blade carries only one of said shades.

6. Rotor according to any one of the preceding claims, wherein the blades have secondary zones tinted adjacent to said tinted areas and located radially inward, these sub-zones bearing dark shades.

7. Rotor according to any one of the preceding claims, wherein, in the radial direction, said specific areas have lengths between 10% and 20% of the length of the blades.

8. A rotor according to any one of the preceding claims, wherein the wavelength of the first hue is selected in a range of 575 to 595 nanometers.