EP3714167A1

EP3714167A1 - Motor fan assembly for motor vehicle

Info

Publication number: EP3714167A1
Application number: EP18822419.0A
Authority: EP
Inventors: Fabrice Ailloud; Bruno Demory; Amanda Martinell
Original assignee: Valeo Systemes Thermiques SAS
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2017-11-24
Filing date: 2018-11-13
Publication date: 2020-09-30
Also published as: FR3074237A1; WO2019102101A1; FR3074237B1

Abstract

The invention relates to a motor fan assembly comprising a wheel and a volute (3) suitable for being mounted on a heating/ventilation and/or air conditioning system, said wheel comprising a hub suitable for being mounted on a drive shaft, and a peripheral ring (17) provided with a series of blades; said volute being suitable for receiving said wheel and comprising an internal wall (30) suitable for moving in part according to a radial angular movement, an air inlet and an air outlet (3d); characterized in that: said wheel comprises at least one blade with an angle of attack between 67° and 79°; the ratio between the interior diameter and the exterior diameter of the wheel is between 75% and 85%; and said volute comprises an angle of extension (a) between 4.7° and 4.9°.

Description

MOTO-VENTILATEU GROUP R POU R VEHICU AUTOMOBILE

DOMAI N E TECH N I A L OF THE I NVE NTI ON

The present invention relates to a motorcycle fan unit for a motor vehicle.

It finds a particular application, but not limited to motor vehicles.

I NV E NTI ON I N A T I N A T I N A T I N A T ION

The present invention relates to the field of air blowers adapted to be mounted on a heating, ventilation and / or air conditioning system for a motor vehicle (generally designated by the acronym HVAC for "Heating, Ventilating and / or Air Conditioning". ").

More particularly, the present invention relates to a motor-blower unit for a heating, ventilation and / or air-conditioning system for a motor vehicle.

Note that a heating system, ventilation and / or air conditioning for a motor vehicle is a housing, usually disposed under the edge of the vehicle board.

Said heating, ventilation and / or air conditioning system comprises:

at least one air inlet, outside or inside;

at least one air outlet opening into the passenger compartment of the motor vehicle;

- Air ducts in which are arranged one or more heat exchangers which will allow to thermally condition (that is to say, heat or cool) an air flow therethrough (said airflow being intended for terminate in the passenger compartment of the motor vehicle via said at least one air outlet). It is, moreover, necessary for the heating / ventilation and / or air conditioning system to be equipped with a motor-fan unit in order to generate a flow of air large enough for said air flow to pass through the heat exchangers and end up in the passenger compartment of the motor vehicle. Thus, the air flow generated by the motor-fan unit must be adapted to compensate for the pressure losses generated by said exchangers and / or the air ducts of said housing.

More particularly, the motor-fan unit comprises an engine mount, a motor housed in the engine mount and a centrifugal-type wheel mounted on the motor shaft of the engine. The motor of the fan motor unit is for example an electric motor.

The motor-fan unit is also mounted on the heating, ventilation and / or air conditioning system at a volute. The volute is for example defined by the walls of the housing of the heating, ventilation and / or air conditioning system. It will be noted that the volute is an air duct having a variable section, generally mathematically determined, which guides the flow of an air flow. In the automotive field, the volute includes a volute air inlet and a volute air outlet that are disposed substantially orthogonally relative to each other.

The wheel disposed in the volute makes it possible to draw the air axially through the air inlet of the volute (that is to say along an axis substantially parallel to the axis of revolution of the wheel) and to push back radially (that is to say along an axis substantially orthogonal to the axis of revolution of the wheel) the air thus sucked by the air outlet of the volute.

It will be noted that the assembly "fan motor unit and volute" is generally referred to as the "air blower".

This type of motor-fan unit also needs to meet many technical requirements, such as acoustics, energy consumption of the engine, engine torque, volume flow rate of the air flow generated by the blower. air, etc. It is generally sought to optimize the transformation of the mechanical power, delivered by the motor via the motor shaft, into a ventilation power delivered via the wheel of the air blower.

If we consider aeration efficiency defined as the ratio of the aeraulic power to the mechanical power, it is thus sought to have aeraulic efficiency closest to 1, indicating that the transformation of the mechanical power into aeraulic power s' performs with as little loss as possible.

I NV E NTI ON G ENERAL C OUNCIL

Thus, the present invention proposes to improve the ventilation efficiency of a motor-fan unit and concerns a motor-fan unit comprising a wheel and a volute adapted to be mounted on a heating / ventilation and / or air conditioning system for a vehicle. automotive,

- said wheel comprising:

- A hub adapted to be mounted on a motor shaft;

- A peripheral ring provided with a succession of blades, said hub and the peripheral ring being connected to one another;

said volute comprising:

an inner wall adapted to evolve in part according to a radial angular evolution;

- an air inlet and an air outlet;

and being adapted to receive said wheel, said wheel being adapted to be disposed in said volute coaxially around a motor of said fan motor unit;

characterized in that

said wheel comprises at least one blade whose angle of attack is between 67 ° and 79 °;

the ratio between the inside diameter and the outside diameter of the wheel is between 75% and 85%; and said volute comprises a development angle of between 4.7 ° and 4.9 °, said development angle being the angle between said inner wall of said volute and said peripheral ring of said wheel.

Surprisingly, and despite many parameters that can be modified, the fact of designing a motor-fan unit having the characteristics set out above makes it possible to improve the energy efficiency of the motor-fan unit. More particularly, it was found, compared to an air blower of the prior art and the same aeraulic power, that the mechanical power needed was lower and therefore the air flow efficiency of the motor-fan unit was improved.

According to non-limiting embodiments, the motor-blower unit may further comprise one or more additional characteristics among the following:

According to a non-limiting embodiment, said wheel has a height of between 60 mm and 90 mm.

The motor-fan unit wheels, which have a height of between 65 and 85 mm, provide further improved performance.

According to a nonlimiting embodiment, said peripheral ring comprises a succession of blades configured to suck the air axially from the inside of the wheel and push it radially outwardly of the wheel. The term "axially" means that the air is sucked along an axis substantially parallel to the axis of revolution of the wheel.

According to a non-limiting embodiment, the hub is connected to the peripheral ring via a connecting means. Said connecting means is, for example, mechanical, such as an open surface or a closed surface.

Generally, the connecting means which connects the hub to the peripheral ring defines a generally concave bowl-shaped envelope. This form is preferably chosen for acoustic reasons. The connecting means is connected for example with the hub in the center of the bowl and with the crown at the periphery of the bowl. According to a non-limiting embodiment, the wheel has an outer diameter of between 135 mm and 165 mm, and preferably between 140 and 160 mm.

The motor-fan unit wheels having a diameter as indicated above exhibit further improved performance.

According to a non-limiting embodiment, said wheel comprises at least one blade whose angle of flight is between 155 ° and 167 °.

The motor-fan unit wheels which comprise at least one blade as indicated above exhibit further improved performance.

The angle of flight of a blade corresponds to the angle between the air flow and the outer transverse end of a blade.

According to a non-limiting embodiment, the ratio between the inside diameter and the outer diameter of the wheel is between 78.3% and 80.3%. The motor-fan unit wheels which have a ratio between the inside diameter and the outer diameter of the wheel which is between 78.3% and 80.3% show improved performance.

According to a non-limiting embodiment, the ratio between the inside diameter and the outside diameter of the wheel is between 78.8% and 79.8%. The motor-fan unit wheels which have a ratio between the inside diameter and the outer diameter of the wheel as indicated above show improved performance compared to the previously indicated values.

According to a non-limiting embodiment, the angle of attack is between 70 ° and 76 °.

According to a non-limiting embodiment, the angle of attack is between 72 ° and 74 °.

The motor-fan unit wheels which have one or more blades with an angle of attack as indicated above show improved performance compared to the previous values. According to a non-limiting embodiment, said wheel comprises less a blade which has a thickness of between 0.8 mm and 2.1 mm, and preferably between 0.9 and 2 mm.

An air blower wheel with one or more blades that have a thickness as indicated above displays the best compromise between aeraulic efficiency and noise nuisance.

According to a non-limiting embodiment, the thickness of the blade is preferably constant, nevertheless due to manufacturing methods, the thickness of the blade can vary from single or double over the height of said wheel.

According to a nonlimiting embodiment, said volute comprises a cutoff defined between a beginning of the radial angular evolution of said volute and an edge of said air outlet, said cutoff being defined by a cutoff angle of between 45.degree. 65 °. This makes it possible to improve the ventilation efficiency of the motor-fan unit.

In a preferred non-limiting embodiment, the cutoff angle is between 52 ° and 59 °.

In a very preferred non-limiting embodiment, the cutoff angle is between 52 ° and 55 °.

According to a non-limiting embodiment, said cut is between 9% and 1 1% of the outer diameter of said wheel.

This makes it possible to adapt the value of the radius of the cut to the dimension of the air blower.

According to a non-limiting embodiment, said volute comprises a cutoff distance of between 8% and 10% of the outer diameter of said wheel. This makes it possible to improve the ventilation efficiency of the fan motor unit.

In a preferred non-limiting embodiment, the breaking distance is between 9.2% and 10% of the outer diameter of said wheel. In a very preferred non-limiting embodiment, the breaking distance is between 9.3% and 9.7% of the outside diameter of said wheel.

The cutoff distance corresponds to the distance between the inner wall at the beginning of the cut (ie at the beginning of the radial angular change) and the peripheral ring of the wheel.

According to a non-limiting embodiment, said wheel has an outer diameter of between 130 mm and 165 mm.

In a preferred non-limiting embodiment, said peripheral ring of said wheel comprises an outer diameter of between 136 mm and 142 mm.

In a very preferred non-limiting embodiment, said peripheral ring of said wheel comprises an outer diameter of between 136 mm and 141 mm.

According to a nonlimiting embodiment, said volute has a first radial dimension of between 175 mm and 212 mm and a second radial dimension perpendicular to the first radial dimension of between 195 mm and 246 mm. This makes it possible to improve the ventilation efficiency of the motor-fan unit

In a preferred non-limiting embodiment, said volute has a first radial dimension of between 186 mm and 202 mm. In a preferred non-limiting embodiment, said volute has a second radial dimension of between 228 mm and 232 mm. In a very preferred non-limiting embodiment, said volute has a first radial dimension of between 190 mm and 202 mm. In a very preferred non-limiting embodiment, said volute has a second radial dimension of between 229 mm and 232 mm.

According to a non-limiting embodiment, said air outlet comprises a substantially rectangular section and comprises a height of between 85 mm and 1 10 mm and a width of between 35 mm and 65 mm. This reduces the size of the motor-fan unit.

In a preferred non-limiting embodiment, said air outlet comprises a height of between 85 mm and 104 mm. In a preferred non-limiting embodiment, said air outlet comprises a width of between 56 mm and 65 mm.

In a very preferred non-limiting embodiment, said air outlet comprises a height of between 85 mm and 95 mm.

In a very preferred non-limiting embodiment, said air outlet comprises a width of between 56 mm and 62 mm.

According to a nonlimiting embodiment, the radial angular evolution of the inner wall is an exponential radial angular evolution.

According to a non-limiting embodiment, the motor-fan unit comprises decoupling means arranged between the motor and the motor support.

According to a non-limiting embodiment, the motor-fan unit comprises an engine control module. Said engine control module is for example mounted on the motor support of the motor-fan unit.

The invention also relates to a heating, ventilation and / or air conditioning system for a motor vehicle comprising a motor-fan unit according to any one of the preceding characteristics.

BRIEF DESCRIPTION OF THE FIGURES

The invention and its various applications will be better understood on reading the following description and examining the figures that accompany it:

- Figure 1 shows a schematic view of a motor-fan unit for a heating system, ventilation and / or air conditioning, according to a non-limiting embodiment;

FIG. 2 represents a perspective view of the motor-fan unit of FIG. 1 and of a part defining volute, according to a non-limiting embodiment;

- Figure 3 is a partially cutaway view of Figure 1, according to a non-limiting embodiment;

- Figure 4 is an exploded perspective view of the elements shown in Figure 1, according to a non-limiting embodiment; FIGS. 5a to 5d show perspective and top views of a wheel of the motor-fan unit of FIG. 1, according to non-limiting embodiments;

- Figure 6 is an enlarged view of the blades of the wheel shown in Figure 5c;

Figure 7 is a cross-sectional view of a blade shown in Figure 6;

- Figure 8 is a longitudinal sectional view of the wheel shown in Figure 5c;

- Figure 9 is a schematic cross-sectional view of a volute of Figure 1, according to a non-limiting embodiment;

- Figure 10 is a schematic cross-sectional view of a radial angular evolution of the volute of Figure 9, according to a non-limiting embodiment;

FIG. 11a is a comparative curve of the aeraulic efficiency as a function of the flow rate provided, for a motor-fan unit according to the invention and a motor-fan unit according to the state of the art;

FIG. 11b is a comparative curve of the electrical consumption as a function of the flow rate provided, for a motor-fan unit according to the invention and a motor-fan unit according to the state of the art;

- Figure 1 1 c is a comparative curve of the noise level as a function of frequency, for a motor-fan unit according to the invention and a motor-fan unit according to the state of the art.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Identical elements, structure or function, appearing in different figures retain, unless otherwise specified, the same references.

FIG. 2 is a diagrammatic perspective view of a motor-fan unit 1 and a part 3, defining a volute, of a heating, ventilation and / or air-conditioning system HVAC for a motor vehicle, the motor-fan unit being mounted on the heating, ventilation system and / or HVAC air conditioning.

It will be noted that an HVAC heating, ventilation and / or air conditioning system for a motor vehicle is a case, generally located under the edge of the motor vehicle, which comprises:

at least one air inlet, outside or inside;

- Air ducts in which are arranged one or more heat exchangers which will allow to thermally condition (that is to say, heat or cool) an air flow therethrough.

Said air flow is intended to end up in the passenger compartment of the motor vehicle via said at least one air outlet of said housing. A heating system 100, ventilation and / or HVAC air conditioning for a motor vehicle is illustrated schematically in Figure 1 in a non-limiting embodiment. He understands :

- A fan motor unit 1 with a volute 3, delivering a stream of air F1 in an air channel 8;

- said air channel 8;

an evaporator 4 of a refrigeration circuit (when the cooling function is present) disposed in the air channel 8;

- A heat sink 5 liquid heat exchanger disposed in the air channel 8 and traversed by a cooling fluid of the electric motor of the motor vehicle; and

- optionally an additional electric heat sink 6 arranged in the air channel 8.

In air-conditioning mode, the air flow F1 is deflected in a passage 7 bypassing a heat sink 5. Downstream of the heat sinks 5 and 6, the air channel 8 distributes the flow of air F1 to mouths exit in the passenger compartment of the motor vehicle. The distribution and optionally the mixing of the F1 air flow are done using controlled shutters (not shown). The mixing allows the temperature regulation of the air flow F1 before the distribution in the cockpit. The distribution and mixing being known to those skilled in the art, they are not described here.

It is also necessary for the heating / ventilation and / or HVAC system to be equipped with a motor-fan unit in order to generate an air flow large enough for said airflow to pass through the the heat exchangers and thus compensate the pressure drops generated by said heat exchangers and / or the air ducts.

It is generally defined a minimum pressure value, denoted for example DR, that the motor-fan unit must produce in order to generate a flow of air sufficient for the latter to pass through one or more heat exchangers and the ducts of the heating system, ventilation and / or HVAC air conditioning and open into the passenger compartment, for a given air volume flow rate (the minimum pressure value DR must therefore be equal to or greater than the pressure losses). There are, moreover, requirements as to the duration for which the air of the passenger compartment has been completely renewed, this in order to avoid odors and / or accumulation of pathogens in the passenger compartment.

As illustrated in FIG. 2, the part of the casing defining the volute 3 generally comprises two parts, upper and lower (respectively 3a and 3b), whose inner surfaces of the walls make it possible to define an air duct having a variable section, generally mathematically determined, which guides the flow of a flow of air F1.

Said volute 3 further comprises a volute air inlet 3c and a volute air outlet 3d. The volute air inlet 3c is connected to the air inlets (interior and / or exterior) of the heating, ventilation and / or air conditioning system 100 HVAC, while the air outlet 3d is connected to one or more HVAC heating, ventilation and / or air conditioning air outlets that terminate in the passenger compartment of the motor vehicle. It will be noted that the volute air inlet 3c and outlet 3d are disposed substantially orthogonally relative to one another.

It will be noted that the assembly "fan motor unit and volute" is generally referred to as the "air blower". The fan motor unit 1 thus comprises a wheel 5 of centrifugal type which is configured to suck the air axially (that is to say along an axis substantially parallel to the axis of revolution of the wheel), by the intermediate of the air inlet 3c of the volute, and to repress air thus sucked radially (that is to say along an axis substantially orthogonal to the axis of revolution of the wheel), so the air is evacuated by the air outlet 3d of the volute 3.

Thus, as can be seen in FIGS. 2 and 3, the fan motor unit 1 comprises:

- a volute 3;

a wheel 5 of the centrifugal type;

a motor support 7;

a motor 9 housed in the motor support, said motor 9 being for example an electric motor.

Said motor 9 further comprises a motor shaft 9a on which the wheel

5 is mounted.

Furthermore, in an embodiment not shown, the motor-fan unit 1 comprises decoupling means arranged between the motor and the motor support.

According to another embodiment not shown, the motor-fan unit 1 comprises a motor control module, said motor control module being for example mounted on the motor support of the motor-fan unit.

The wheel 5 is the means which allows the transformation of the rotation of the drive shaft 9a into an air flow which is characterized by a pressure difference DR and a volume flow rate of air and which passes through the volute, as well as the system 100 heating, ventilation and / or HVAC air conditioning.

The mechanical power corresponds to the product of the speed of rotation of the drive shaft 9a by the mechanical torque delivered by said drive shaft 9a.

The aeraulic power corresponds to the product of the air volume flow rate and the pressure difference generated by the wheel.

Thus, the fact of improving the aeraulic power or of maintaining an identical air power for a lower mechanical power makes it possible to improve the ventilation efficiency of the motor-fan unit, the aeraulic efficiency being the ratio of the aeraulic power to the power. mechanical.

Indeed, if the mechanical power to be supplied is less important, the electric power to be supplied to the electric motor will be less important. Thus, for a similar air power, the power consumption of the engine will be less important.

The wheel 5 and the volute 3 are described in more detail below.

• Wheel 15

Figures 5a to 5d show perspective and top views of non-limiting embodiments of the wheel 5.

More particularly, the wheel 5 comprises:

a hub 15 adapted to be mounted on a motor shaft 9a;

- A peripheral ring 17 provided with a succession of blades 19; said hub 15 and the peripheral ring 17 being connected to each other. In the exemplary embodiments presented, the connecting means is a mechanical link.

The wheel 5 comprises at least one blade 19.

It will be noted that a blade has an elongated shape. The longitudinal axis of a blade is substantially parallel to the axis of revolution of the wheel. A blade therefore has two opposite longitudinal ends and two opposite transverse ends.

Moreover, the centrifugal type wheel 5 has a generally cylindrical shape and an axis of revolution passing through the hub 15. This axis of revolution defines an axis of rotation A illustrated in FIG. 1 of the fan motor unit 1.

Said wheel 5 also has a height and an outside diameter D2. By height means, the spatial extension of the wheel 5 along an axis substantially collinear with the axis of revolution of the wheel 5.

By outside diameter D2 is meant the radial extension of the wheel (the outer diameter of the wheel 5 being included in a plane substantially orthogonal to the axis of revolution of said wheel 5).

In a non-limiting embodiment, the outside diameter D2 is between 130 mm and 165 mm. In a preferred non-limiting embodiment, the outside diameter is between 136 mm and 142 mm. In a very preferred non-limiting embodiment, the outside diameter is between 136 mm and 141 mm.

The wheel 5 also has an inner diameter D1.

By internal diameter D1 is meant the radial inner extension of the wheel 5 (that is to say the outside diameter to which the distance occupied by the blades 19 of the wheel 5) would have been subtracted.

In a non-limiting embodiment, the wheel 5 comprises at least one blade 19 whose angle of attack is between 67 ° (degrees) and 79 ° (degrees).

The angle of attack of a blade 19 is understood to mean the angle of incidence of the air flow on the internal transverse end of the blade 19.

In addition, in a non-limiting embodiment, said wheel 5 has a ratio between its inner diameter D1 and its outer diameter D2 which is between 75% and 85%.

As can be seen in FIGS. 11a, 11b, 11c, such a wheel 5 improves the aeraulic efficiency of the motor-fan unit, while reducing the acoustic nuisance generated by the rotation of the wheel. The wheel 5 makes it possible to reduce the necessary torque provided by the motor shaft and / or the rotational speed of said shaft while ensuring identical airflow performance (that is to say for a pressure and an equivalent air volume flow rate). ).

The curves 50 and 51 represent the aeraulic efficiency as a function of the air flow rate supplied by the motor-fan unit, in the range from 0 to 700 kilograms per hour. Curve 60 corresponds to a motor-fan unit according to art. Curve 61 corresponds to a motor-fan unit according to the invention, in which the design parameters of the wheel and the volute have been optimized.

The curves 60 and 61 represent the electrical consumption as a function of the air flow rate supplied by the motor-fan unit, in the range 0 to 700 kg / h. The curve 60 corresponds to a motor-fan unit according to the art and the curve 61 corresponds to a motor-fan unit according to the invention, in which the design parameters of the wheel and the volute have been optimized.

As can be seen in FIG. 11a, the aeraulic efficiency of the optimized fan motor unit is significantly improved compared with the design according to art. Therefore, and as can be seen in Figure 11b, the power consumption is reduced with the solution according to the invention.

The curves 70 and 71 represent the noise level of the motor-fan unit as a function of the frequency, in the range 0 to 4000 Hz. The curve 70 corresponds to a motor-fan unit according to the art and the curve 71 corresponds to a motor-fan unit according to the invention. The optimized solution according to the invention has a reduced noise level.

Thus, the optimized solution is more efficient than the state of the art on the main performance criteria such as aeraulic efficiency, power consumption and the level of noise emitted.

More particularly, said peripheral ring 17 is provided with a succession of blades 19 configured to suck the air axially from the inside of the ring 17 and to push it radially outwards of the wheel 5.

The term "axially" means that the air is sucked along an axis substantially parallel to the axis of revolution A of the wheel. Generally, the axis of revolution A of the wheel 5 passes through the hub 15 of said wheel.

The hub 15 is connected to the peripheral ring 17 via a connecting means 21. The connecting means 21 defines a generally concave bowl-shaped envelope, which can be closed (visible for example in FIG. 5a) or opened (visible for example in FIGS. 5b, 5c and 5d).

The connecting means 21, also called the bowl of the wheel, is for example an open surface (it is pierced with openings of variable sizes (see for example Figures 5c and 5d), an open surface comprising a plurality of arms (see Figure 5b) which connects the hub 15 to said surface, or closed (see Figure 5a).

The fact that the connecting means 21 is open is generally conditioned by the need to devote a portion of the air flow generated by the wheel 5 to the cooling of the motor 9.

However, a connection means 21 closed has the advantage of generating less noise than an open link 21.

Said connecting means 21 is connected for example with the hub 15 in the center of the bowl and with the ring 17 at the periphery of the bowl.

Furthermore, it will be noted that the wheel 5 generally comprises a connecting ring 23 located at the end opposite to the ring 17 which connects the blades 19 of the wheel with each other, this connecting ring of 23 makes it possible to reinforce the mechanical cohesion of the wheel 5.

FIG. 6, for its part, is an enlarged view of blades 19 of wheel 5.

Each of the blades 19 has an elongate shape and whose longitudinal extension is substantially parallel to the axis of revolution of the wheel 5 (that is to say that the longitudinal axis of a blade is substantially parallel to the axis of revolution of the wheel). Each of the blades therefore has opposite longitudinal ends.

In addition, said opposite longitudinal ends of a blade 19 are respectively connected to the peripheral ring 17 and to the connecting ring 23.

In addition, a blade 19 has, in section, an arcuate profile (more particularly visible in Figure 7). The sectional view corresponds to a cutting plane substantially orthogonal to the longitudinal axis of a blade.

Each of the blades 19 has a first transverse end and a second transverse end, said first and second transverse ends being opposite 19a, 19b relative to each other. Said first transverse end 19a, also called external transverse end, extends away from the hub 15 of said wheel 5 (that is to say that the first transverse end is oriented towards the outside of the wheel).

Said second transverse end 19b, also called internal transverse end, extends towards the hub 15 of said wheel 5 (that is to say that the second transverse end is oriented towards the inside of the wheel).

The first transverse end 19a may also be designated by the term "trailing end", while the second transverse end, as for it, 19b may be designated by the term "leading end" (one can also speak respectively of " "trailing edge" and "leading edge").

Note also that the distance between each of the opposite transverse ends 19a and 19b of a blade 19 is called the rope C (more particularly visible in Figure 7), the rope C corresponds to the distance between the two ends of the blade distance from the concave side of said blade.

In addition, since each of the blades 19 has an arcuate profile, each of the blades has a concave and a convex face opposite to each other.

As illustrated in Figure 7:

each of the blades 19 has an angle of attack b1; the angle of attack b1 of a blade corresponds to the angle between the tangent t2 to the concave face of the second end 19b of the blade and the normal t1 to said end 19b (the normal being substantially tangent to the inner diameter of wheel).

Each of the blades 19 has a leakage angle b2; the angle of flight b2 of a blade corresponds to the angle between, on the one hand, the tangent t4 to the concave face of the first end 19a and, on the other hand, the tangent t3 of the outer diameter of the wheel at the point of intersection between the outer diameter of the wheel and the tangent to the concave face of the first end 19a. The thickness (e) of a blade 19 corresponds to the distance between the opposite longitudinal faces of a blade, that is to say the distance between the concave and convex faces of a blade.

Thus, according to non-limiting embodiments, said air blower wheel 5 comprises at least one blade 19 having one or more of the following characteristics:

The angle of attack b1 of a blade (19) is between 67 ° and 79 °, and preferably between 70 ° and 76 °, and even more preferably between 72 ° and 74 °.

The thickness e of the blade 19 is between 0.8 mm and 2.1 mm, and preferably between 0.9 mm and 2 mm.

The angle of leakage b2 of a blade 19 is between 155 ° and 167 °, and preferably between 157 ° and 165 °, and even more preferably between 159 ° and 163 °.

As illustrated in Figure 8:

The outside diameter D2 of wheel 5 corresponds to the radial extension of the wheel 5, that is to say to a straight line extending from one radial end outside the other of the wheel 5 and passing through the axis of revolution A of the latter (generally the outer diameter of the wheel corresponds to the diameter of the peripheral ring or the connecting ring).

The inside diameter D1 of wheel 5 corresponds to the radial inner extension of the wheel, that is to say to a straight line extending from one internal transverse end 19b of a blade 19 to another 19b and passing through the axis of revolution A of the wheel 5.

The height H of the road 5 corresponds to the longitudinal extension of the wheel 5.

Thus, according to non-limiting embodiments, said impeller wheel 5 has one or more of the following characteristics:

The ratio between the inside diameter D1 and the outside diameter D2 of the wheel 5 is between 75% and 85%, and preferably between 78.3% and 80.3%, and even more preferably between 78.8% and 79%, 8%. The wheel 5 has an outside diameter D2 of between 135 mm and 165 mm, and preferably between 140 and 160 mm.

Said wheel 5 has a height H of between 60 mm and 90 mm, and preferably between 65 and 85 mm.

Note that the wheel 5 preferably comprises at least 50% of blades having one or more of the features set out above, and even more preferably all the blades of said wheel 5 has one or more of the characteristics set out above. .

• Volute 3

The volute 3 is illustrated in plan view in Figures 1 to 4, and 9 and 10.

It is adapted to receive said wheel 5 and receive said engine support 7. The volute 3 comprises in particular:

an opening 3f (illustrated in FIG. 4 and in dashed lines in FIG. 1);

an inner wall 30 (illustrated in FIGS. 1 and 3) comprising:

an air inlet 3c (illustrated in FIG. 2);

an air outlet 3d (illustrated in FIGS. 1 to 4, and 9 and 10);

a cutoff 3g (illustrated in FIGS. 2, 9 and 10);

- A terminal portion 3h disposed between said cut 3g and said air outlet 3d (illustrated in Figures 9 and 10 and partly in Figures 2 and 3).

The motor support 7 is fixed in an opening 3f opposite the air inlet 3c. The motor support 7 delimits a housing for the motor 9. The wheel 5 is arranged around the motor 9 in the volute 3 coaxially with said motor 9.

The inner wall 30 defines an air duct 31 (shown in Figures 1 and 9) in which the air flow F1 can flow. o Input 3c

A first air flow F0, said incoming, illustrated in Figure 1 is drawn axially into the volute 3 by the air inlet 3c and is circulated in said volute 3 to give a second radial air flow F1 which is extracted from the volute 3 by the 3d air outlet. As shown in FIG. 2, the air inlet 3c of the volute 3 is defined by an inner circumference 34 of the upper part 3b of the casing of the volute 3. The peripheral ring 17 of the wheel 5 such as illustrated in Figures 9 and 10 is of outer diameter D2. o 3d air outlet

The 3d air outlet serves as plenum extraction of the second air flow F1. It extends from the 3g cut. In a non-limiting embodiment illustrated in Figure 2, the air outlet 3d comprises a substantially rectangular section, with two edges 32 and 33 vis-à-vis substantially parallel to each other. The edge 32 is opposed to the cut 3g and the edge 33 is adjacent to the cut 3g.

In a non-limiting embodiment, the air outlet 3d has a height H1 of between 85 mm and 1 10 mm and a width L1 of between 35 mm and 65 mm.

In a preferred non-limiting embodiment, said air outlet 3d comprises a height H1 of between 85 mm and 104 mm.

In a preferred non-limiting embodiment, said air outlet 3d comprises a width L1 of between 56 mm and 65 mm.

In a very preferred non-limiting embodiment, said air outlet 3d comprises a height H1 of between 85 mm and 95 mm.

In a very preferred non-limiting embodiment, said air outlet 3d comprises a width L1 of between 56 mm and 62 mm. o 3g break

The cut 3g, also called volute beak, is called "cutoff" or "tongue" in English.

The cut 3g is defined between the beginning of the radial angular evolution of the inner wall 30 of the volute 3 and the edge 33 of the air outlet 3d. It thus makes the connection between the two. It starts at the beginning of the radial angular evolution and ends at the edge 33 of the 3d air outlet.

In a nonlimiting embodiment illustrated, the cut 3g has a curvature defined by a circle 4 of center C and radius of curvature Rc. She is defined by a cut-off angle 0 _C described below. In a nonlimiting embodiment, said cut 3g is between 9% and 1 1% of the outer diameter D2 of the wheel 5.

o Part. termi n ale 3 h

The terminal part 3h leads to the 3d air outlet.

As illustrated in Figures 9 and 10, it includes:

a rectilinear sub-portion 3h adjacent to the end of the radial angular evolution of the inner wall 30;

a rectilinear sub-portion 3h adjacent to the end of the cut 3g.

In a non-limiting embodiment, the two subparts 3h 'and 3h "are substantially partly parallel to each other. As can be seen, the two subparts 3h 'and 3h "do not have the same length, subpart 3h' being larger than subpart 3h".

The inner wall 30 comprises a variable section, generally mathematically determined. Thus, the inner wall 31 evolves in a radial angular evolution. As illustrated in Figures 9 and 10, the volute 3 is for this purpose determined by different characteristics, including:

- a development angle a;

a radius of radial evolution r;

a cut-off angle θc, also called volute spout position angle; and

- a cut-off distance i.

These characteristics are described below. o Angje.de development has

The development angle a is illustrated in FIG. 9.

It is called in English "expansion angle".

The angle of development a is the angle between the inner wall 30 of the volute 3 and the peripheral ring 17 of the wheel 5.

The development angle a is a function of the distance between the inner wall 30 and the peripheral ring 17 of the wheel 5. In one embodiment non-limiting, this distance varies linearly. Thus, the development of the inner wall 30 is performed at a constant development angle a.

The distance is represented in FIG. 9 by the distances b to i which are the respective distances between the points B to I situated on the inner wall of the volute 3 and the peripheral ring 17 of the wheel 5. As can be seen on In Figure 9, apart from point I, an angle of 45 ° (degrees) separates each projection of points B to H on the peripheral ring 17 from at least one other projection on said peripheral ring 17 from an adjacent point. It will be noted that the projections of the points B and H have an angle of 45 ° with only one projection of an adjacent point, namely respectively with the projections of the points G and C, while the projections of the points C to G present a 45 ° angle with two projections of adjacent points.

Thus, between two projections of two adjacent points, the distance, namely the arc of circle, on the circle represented by the peripheral ring 17 of the wheel 5 is therefore pϋ2 / 8, namely 0.125p D2. It will be noted that the point A represents the full angle, namely the distance p2.

It will be noted that the point I is the point which is at the cut-off angle θc described below. In a non-limiting embodiment, the distance from point I is the cutoff distance i described below.

In a nonlimiting embodiment, the development angle a is between 4.7 ° (degrees) and 4.9 ° (degrees).

The angle of development a and the diameter D2 of the peripheral ring 17 of the wheel 5, as well as the radius of radial evolution r described below, determine a first radial dimension XX and a second radial dimension YY of the volute 3 illustrated in Figure 9. The radial dimension YY is perpendicular to the radial dimension XX.

In a non-limiting embodiment, the first radial dimension XX is between 175 mm and 212 mm and the second radial dimension Y-Y is between 195 mm and 246 mm. In a preferred non-limiting embodiment, said volute has a first radial dimension of between 186 mm and 202 mm. In a preferred non-limiting embodiment, said volute has a second radial dimension of between 228 mm and 232 mm. In a very preferred non-limiting embodiment, said volute has a first radial dimension of between 190 mm and 202 mm. In a very preferred non-limiting embodiment, said volute has a second radial dimension of between 229 mm and 232 mm. It will be noted that, thanks to the characteristics of the development angle a, the gain in electrical power and the airflow efficiency are improved. Thus, the gain in electrical power is improved.

Thus, a lower electric power is provided to ensure identical aeraulic performance or equivalent electrical power is provided to ensure better aeraulic performance. o Ray. of radial evaporation. r

The radius of radial evolution r is illustrated in FIGS. 9 and 10.

The inner wall 30 of the volute 3 evolves in a radial angular evolution in a radial direction relative to the axis of revolution A. The radial angular evolution begins at the cut 3g, namely at the point I illustrated in FIG. and ends at point B illustrated in FIG. 9 which defines the end of the radial angular evolution, point B being close to exit 3d. Thus, the cut 3g (more particularly the beginning of the cut 3g) defines a first end I of the radial angular evolution of the volute 3, and the point B defines a second end of the radial angular evolution of the volute 3. Near the cut 3g, the radial dimension of the inner wall 30 is smaller than that near the 3d exit.

After the cutoff 3g, more particularly at the end of the break 3g, the inner wall 30 extends via its sub-portion 3h "of its end portion 3h to the air outlet 3d of the volute 3.

From the second end B, the inner wall 30 extends via its sub-portion 3h 'of its end portion 3h to the air outlet 3d of the volute 3. The inner wall 30 of the volute 3 thus comprises a radius r, called radius of radial evolution, having a radial angular evolution as a function of a radial evolution angle Q so that said inner wall 30 forms a spiral.

The radial evolution angle Q is taken in a plane perpendicular to the axis of rotation A of the motor-fan unit, namely the axis of revolution A of said road 5. It is called in English "radial evolution angle" .

The radius r is defined from the axis of revolution A to the inner wall 30 in the direction of rotation of the wheel 5 and the direction of the second air flow F1 represented by the arrow illustrated in FIG. 10 representing the radial angular evolution of the volute 3. Thus, the radius ra a minimum length at the cut 3g and a maximum length at the end of the radial evolution which is adjacent to the edge 32 of the air outlet 3d opposite to the cut 3g. Note that the end portion 3h of the inner wall 30 has been shown in dotted lines for the sake of understanding.

In a nonlimiting embodiment illustrated in FIG. 10, the radial angular change is an exponential radial angular change in the relation r = t0bcr (I0p 0/180 °) with:

- Q the radial evolution angle between a cut-off angle 0 _C and a maximum radial evolution angle QM;

rO, the radius of the inner wall 30 for 0 = 0 _C ;

- I0 a constant.

0M corresponds to the end of the radial evolution, in the vicinity of the edge 32 of the air outlet 3d. It corresponds in Figure 10 to the 360 ° angle starting from 0 ° and 360 ° - 0c from the beginning of the radial evolution.

As illustrated in FIG. 10, it will be noted that the beginning of the radial evolution of the volute 3 is defined by the intersection of a virtual line D3 passing through the axis of rotation A of the motor-fan unit the wall internal 30 of said volute 3, and passing through the center C of the circle 4 defining the curvature of the cut 3g of said volute 3.

In another nonlimiting embodiment not illustrated, the evolution radial angular is a logarithmic radial angular evolution o Angje.de cutoff .0c

The cut-off angle θc is illustrated in FIG.

The cutoff angle Oc is called in English "cutoff angle".

It determines the limit where the radial evolution of the volute 3 begins and the beginning of the cut 3g which is in the vicinity of the edge 33 of the output 3d of the volute 3.

The cutoff angle 0c is defined between the end of the radial evolution of the volute

3 and the beginning of the radial evolution of the volute 3 as illustrated in Figure 10. Thus, its origin begins at the end of the radial evolution. The end of the radial evolution is represented by 360 ° in FIG.

In a non-limiting embodiment, the cutoff angle θ is between 45 ° and 65 °. In a preferred non-limiting embodiment, the cutoff angle θ is between 52 ° and 59 °. In a very preferred non-limiting embodiment, the cut-off angle est is between 52 ° and 55 °.

The cutoff angle θ thus determines a cut in the inner wall 30 of the volute 3 as illustrated by the dashed curve in FIG.

The cutoff angle Oc as characterized above also contributes to the reduction of the sound level of the motor-fan unit 1 and the reduction of the electric power used. o Cut-off pattern j.

The cutoff distance i is illustrated in FIG. 9 and FIG.

It corresponds to the distance between the inner wall 30 at the beginning of the cut 3g (namely at the beginning of the radial angular evolution) and the peripheral ring 17 of the wheel 5. This corresponds to the distance between the blades of the wheel 5 and the cut 3g, when said wheel 5 comprises pale. This distance i is on the virtual line D3 which passes through the center C of the circle

4 defining the curvature of the cut 3g.

In a non-limiting embodiment, the cut-off distance i is included between 8% and 10% of the outer diameter D2 of the wheel 5. In a preferred non-limiting embodiment, the cutoff distance is between 9.2% and 10% of the outer diameter of said wheel. In a very preferred non-limiting embodiment, the breaking distance is between 9.3% and 9.7% of the outer diameter of said wheel.

Thus, the volute 3 which has at least one of the characteristics as described improves the air flow efficiency of the motor-fan unit 1, while reducing the noise generated by the rotation of the wheel 5 in the volute 3. More the motor-fan unit 1 provides a high airflow, plus we save in terms of electrical power.

Furthermore, the volute 3 makes it possible to reduce the necessary mechanical torque provided by the drive shaft 9a and / or the speed of rotation of said drive shaft 9a while ensuring identical airflow performance (that is to say for a pressure and a volume flow equivalent air). Thus, the electrical power needed to run the engine is reduced.

Of course, the description of the invention is not limited to the application and to the embodiments described above.

Thus, in another non-limiting embodiment, the fan motor unit 1 is a motor-fan unit for heating, ventilation and / or air conditioning system for residential or industrial buildings. Thus, in another non-limiting embodiment, the development of the inner wall 30 is performed at a variable development angle.

Thus, the invention described has the following advantages:

thanks to the volute 3 thus characterized, the electrical power to be supplied to the motor 9 is reduced to bring it into rotation, which makes it possible to improve the efficiency of the engine, said efficiency of the motor being equal to the ratio of the mechanical power produced on the electric power used. This reduces the power consumption of the engine 9;

- thanks to the volute 3 thus characterized, we increase the aeraulic power the motor-fan unit 1. The air flow efficiency is thus improved;

thanks to the improved motor efficiency and ventilation efficiency, the overall efficiency of the motor-fan unit 1 is improved, the overall efficiency being equal to the efficiency of the motor multiplied by the aeraulic efficiency. In other words, the overall efficiency is equal to the ratio of the electrical power consumed on the generated air power; thanks to the volute 3 thus characterized, to obtain aeration efficiency identical to the prior art, the mechanical power is improved thanks to a decrease in the mechanical torque delivered by the drive shaft 9a and / or a decrease in the speed of rotation of said motor shaft 9a. The reduction of the mechanical torque makes it possible to reduce the electrical consumption of the motor 9. The reduction in the speed of rotation of said motor shaft 9a makes it possible to reduce the acoustic level of the motor-fan unit 1. These improvements come from the very particular combination of the individual characteristics. the wheel and the volute of the motor-fan unit, which have a synergetic effect.

Claims

Motor-fan unit (1) comprising a wheel (5) and a volute (3) adapted to be mounted on a heating / ventilation and / or air conditioning (HVAC) system for a motor vehicle,

said wheel (5) comprising:

- a hub (15) adapted to be mounted on a drive shaft (9a) - a peripheral ring (17) provided with a succession of blades (19), said hub (15) and the peripheral ring (17) being connected to one to another;

said volute (3) comprising:

- an inner wall (30) adapted to evolve in part in a radial angular evolution;

an air inlet (3c) and an air outlet (3d);

and being adapted to receive said wheel (5), said wheel (5) being adapted to be disposed in said volute (3) coaxially around a motor (9) of said motor-fan unit (1);

characterized in that

said wheel (5) comprises at least one blade whose angle of attack (b1) is between 67 ° and 79 °;

the ratio between the inside diameter (D1) and the outside diameter (D2) of the wheel is between 75% and 85%; and

said volute (3) comprises a development angle (a) of between 4.7 ° and 4.9 °, said development angle (a) being the angle between said inner wall (30) of said volute (3) and said peripheral ring (17) of said wheel (5).

2. motor-fan unit (1) according to claim 1, characterized in that said wheel (5) has a height (H) of between 60 mm and 90 mm, and preferably between 65 and 85 mm.

3. motor-fan unit (1) according to claim 1 or claim 2, characterized in that said wheel (5) comprises at least one blade whose angle of leakage (b2) is between 155 ° and 167 °.

Fan motor unit (1) according to one of Claims 1 to 3, characterized in that the ratio of the inner diameter (D1) to the outer diameter (D2) of the wheel is 78.3%. and 80.3%.

5. fan motor unit (1) according to any one of claims 1 to 4, characterized in that the angle of attack (b1) is between 70 ° and 76 °.

6. fan motor unit (1) according to any one of claims 1 to 5, characterized in that said wheel comprises less than a blade (19) having a thickness (e) between 0.8 mm and 2.1 mm.

7. Fan motor unit (1) according to any one of claims 1 to 6, characterized in that said volute (3) comprises a cut (3g) defined between a beginning of the radial angular evolution of said volute (3). ) and an edge (33) of said air outlet (3d), said cutoff (3g) being defined by a cutoff angle (0c) of between 45 ° and 65 °.

8. motor-fan unit (1) according to claim 7, characterized in that said cut (3g) is between 9% and 1 1% of the outer diameter (D2) of said wheel (5).

Motor-fan unit (1) according to claim 7 or 8, characterized in that said volute (3) comprises a cut-off distance (i) of between 8% and 10% of the outer diameter (D2) of said wheel ( 5).

10. fan motor unit (1) according to any one of claims 1 to 9, characterized in that said wheel (5) has an outer diameter (D2) of between 130 mm and 165 mm.