Air guide for a motor vehicle cooling device having a round front upper edge for pedestrian impact

Abstract

The invention relates to an air guide (110) for a cooling device (100) that is intended to be fixedly installed in the engine compartment of a motor vehicle between the front fascia and the cooling unit (10) of said vehicle, the air guide (110) comprising a hollow main body (111) having a substantially parallelepiped shape comprising a front face (112) bordered by a peripheral frame (113) extending therebehind, the front face (112) having at least one through-window formed in the lower portion thereof that is intended to face a controlled module (120) for regulating the incoming airflow; characterised in that the cross-section of the front upper edge (117) of the main body (111), connecting the front face (112) to the upper wall of the peripheral frame (113), has a rounded arc-shaped profile.

Description

Description AIR GUIDE FOR AUTOMOTIVE COOLING DEVICE FEATURING A ROUNDED FRONT TOP EDGE FOR PEDESTRIAN IMPACT [Technical field] [1] The present invention claims priority from French application 2202795 filed on March 29, 2022, the content of which (text, drawings and claims) is incorporated herein by reference. [2] The present invention relates generally to air-guided cooling devices intended to be installed at the front of the engine compartment of motor vehicles to cool the heat exchangers of these vehicles. [Previous technique] [3] The regulation of the incoming cooling airflow of a motor vehicle is generally ensured by at least one first air inlet called the low-way inlet provided on the front bumper skin of the vehicle and extending vertically between the beams of the lower and upper reinforcements of the front bumper of this vehicle. [4] Thus, when the vehicle is moving, a quantity of more or less cool air is received inside the engine compartment by the vehicle's cooling cassette, which includes the various elements necessary for cooling the engine, such as generally an engine water radiator, a condenser, and possibly a second radiator for cooling the turbo or the battery of the hybrid electric motor. [5] The amount of air entering under these conditions depends directly on the speed of the vehicle, the dimensions of the air intake(s), and the power of the fan(s) of the motor-fan unit when they are in operation. [6] However, these air inlets are of fixed dimensions, so the flow rates and temperatures of the cooling air cannot be controlled because they are directly related to the vehicle's speed and outside air temperature. Consequently, the vehicle's engine compartment components located under the hood can be excessively cooled under certain conditions, particularly in winter when outside temperatures are low. [7] In addition, this air entering the vehicle via the grille has the effect of degrading the aerodynamic drag coefficient SCx of the vehicle (this coefficient corresponding to the drag coefficient (Cx) multiplied by a reference area (S)) and consequently increasing the CO2 emissions of the vehicle. [8] It is known, in particular from document FR 3010947 A1, to insert longitudinally, between the front shield and the cooling cassette of a motor vehicle, a cooling device comprising an air guide including a main hollow body of substantially parallelepiped shape fixed to the structure of the motor vehicle and comprising a front face bordered by a peripheral frame extending behind the latter. [9] This front facade has at least one passage window in its lower part opposite an air intake on the front bumper of the vehicle.

[0010] Such a cooling system also includes a controlled airflow regulation module with blackout flaps, which attaches to the air guide in front of and opposite this passage window.

[0011] This control module includes a plurality of flaps mounted pivoting around parallel axes between a closed position and an open position, as well as means for controlling the movement of said flaps between these two positions, so as to regulate the incoming airflow.

[0012] Regulatory impact tests simulating a 40 km / h collision between a pedestrian and the front of a motor vehicle unfortunately show that the upper front edge of the main body of the air guide (i.e. the edge connecting the front facade to the upper wall of the peripheral frame of this body) constitutes a hard point opposing the recoil of the grille area located just in front of this edge, which can lead to risks of injury to the pelvis and / or upper legs (femur areas) of this pedestrian. [Description of the invention]

[0013] The present invention therefore aims to improve the situation.

[0014] It proposes for this purpose an air guide for a cooling device intended to be fixedly installed in the engine compartment of a motor vehicle between the front bumper and the cooling cassette of that vehicle, said air guide comprising a hollow main body of substantially parallelepiped shape including a front face bordered by a peripheral frame extending behind the latter, said front face having at least one passage window provided in its lower part and intended to face a controlled regulation module of the incoming airflow; characterized in that the upper front edge of said main body, connecting the front face to the upper wall of the peripheral frame, has in section a rounded profile in the form of an arc of a circle.

[0015] Such a rounded profile of this upper front edge facilitates its deformation and indentation in the event of a pedestrian collision with the front of the vehicle so as to allow the vehicle's grille area located just in front of this edge to move back, resulting in a significant reduction in the risk of injury to the pelvis and / or upper leg areas (femur areas) of this pedestrian.

[0016] According to preferred characteristics of said air guide according to the invention: - said rounded profile has a radius greater than or equal to 30 mm; - said radius is between 40 and 60 mm; - said upper front edge has several deformation zones made of a more flexible material than the rest of this edge and distributed transversely at regular intervals from each other along this edge; - said deformation zones are made of an elastomeric material; - said deformation zones extend onto the upper part of said front facade; - each deformation zone has a necking line of least resistance extending in a vertical longitudinal plane and configured to break under a predetermined longitudinal shear stress; - each of these necking lines consists of a groove thinning carried out on the outer face of said upper front edge; and / or the side walls of said peripheral frame have in section an accordion profile or extend diagonally from the inner side towards said front face.

[0017] The invention also relates in a second aspect to a cooling device intended to be fixedly installed in the engine compartment of a motor vehicle between the front bumper and the cooling cassette of that vehicle, said device comprising such an air guide as well as a controlled regulation module of the incoming airflow with movable flaps, mounted in a sealed manner on said air guide opposite said passage window. [Brief description of the drawings]

[0018] The description of the invention will now be continued by a detailed description of several embodiments, given below by way of illustration but not limitation, with reference to the attached drawings, on which:

[0019] [Fig 1] represents a three-quarter front perspective view of the front part of the engine compartment of a motor vehicle comprising a cooling device with an air guide according to the invention; and

[0020] [Fig 2] is a perspective view of the air guide according to the invention shown alone. [Detailed description]

[0021] Figure 1 represents the front part of the engine compartment of a motor vehicle comprising a cooling device 100 according to the invention interposed longitudinally between the front bumper (not shown) of this vehicle having an air intake in the lower part and the cooling cassette of this vehicle 10 comprising various heat exchangers 11, 12 (namely and from back to front, the radiator 11 of the cooling circuit of the internal combustion engine and the condenser 12 of the circuit of the air conditioning system).

[0022] In the description that follows, and by convention, we define an orthogonal XYZ coordinate system with respect to the vehicle, comprising three axes perpendicular to each other in pairs, namely: - an X-axis, defining a longitudinal, horizontal direction, coinciding with the general direction of vehicle movement, - a Y-axis, defining a horizontal, transverse direction, which, together with the X-axis, defines a horizontal XY plane, and - a Z axis, defining a vertical direction, perpendicular to the horizontal XY plane.

[0023] In the remainder of this description and with reference to the coordinate system defined above, the terms "longitudinal" or "longitudinally" will refer to a direction parallel to the X-axis, the terms "transverse" or "transversely" will refer to a direction parallel to the Y-axis, and the terms "vertical" or "Vertically" will refer to a direction parallel to the Z-axis.

[0024] The terms "external" and "internal" will be used to define the relative position of an element with reference to the longitudinal axis of the vehicle. The element closest to this axis will thus be described as internal, as opposed to the other element further from this same axis, which will be described as external.

[0025] The cooling device 100 includes an air guide 110 covering the front face of the cooling cassette 10 and attached to the latter as will be seen in more detail later.

[0026] This air guide 110 includes a hollow main body 111 of substantially parallelepiped shape extending longitudinally between, at the front, the metal beams 21, 31 of the lower 20 and upper 30 reinforcements of the front bumper of the vehicle, and at the rear, the cooling cassette 10.

[0027] This main body 111 includes a rectangular front face 112 bordered by a peripheral frame 113 extending behind this face 112 and fitting fixedly and in a sealed manner around the perimeter of the cooling cassette 10.

[0028] As illustrated in Figures 1 and 2, the attachment of the peripheral frame 113 of this air guide 110 to the cooling cassette 10 is ensured via four fixing tabs 114 protruding from the lateral faces of this frame 113 and screwing into corresponding fixing members 12A provided on the condenser 12.

[0029] With reference to figure 2 and in order to ensure sealing with the perimeter of the cooling cassette 10, the rear portion 113A of this peripheral frame 113 is made of a more flexible material than the front portion 113B, for example in an elastomeric material.

[0030] The front facade 112 has in its lower part a window of substantially rectangular shape 115 extending over its entire width and arranged vertically between the metal beams 21, 31 of the lower reinforcements 20 and upper reinforcements 30 of the front bumper of the vehicle, so as to be opposite the air intake of the front bumper of the vehicle.

[0031] The air guide 110 also includes a guide duct 116 extending in front of the body 111 from and along the peripheral perimeter of the window 115, flaring out laterally.

[0032] As illustrated in Figure 1, the cooling device 100 further comprises a pilot-controlled incoming airflow regulation module 120 projecting in front of the guide duct 116 into which it is fixedly and tightly fitted, so as to be located opposite the window 115 and the air intake of the front bumper of the vehicle.

[0033] With further reference to Figure 1, this regulation module 120 comprises a hollow housing 121 defining two lateral support compartments of identical widths extending symmetrically on either side of a central compartment of smaller width.

[0034] This 120 regulation module also includes several blackout flaps 122 arranged one above the other in each of the lateral support compartments and mounted pivoting around their transversely oriented axes between a closed position illustrated by Figure 1 and an open position.

[0035] A motorized control mechanism (not visible) located at the central compartment and intended to be connected to the vehicle's electrical power supply circuit also allows the movement of said flaps between their open and closed positions to be controlled.

[0036] The attachment of this controlled incoming airflow regulation module 120 to the guide duct 116 is, for example, ensured by clipping means not shown provided on housing 121 and intended to cooperate by snapping with corresponding means provided on this conduit 116.

[0037] This fixing can also be done by different means, for example by screwing.

[0038] In order to ensure sealing with the perimeter of the housing of this control module 120, the front portion 116B of the guide conduit 116 is advantageously made of a more flexible material than its rear portion 116A, for example in an elastomeric material.

[0039] According to the invention, the upper front edge 117 of the main body 111, connecting the front facade 112 to the upper wall of the peripheral frame 113, has in section a rounded profile in the shape of an arc of a circle whose radius, advantageously greater than or equal to 30 mm, is preferably between 40 and 60 mm.

[0040] Such a rounded profile of this upper front edge 117 facilitates its deformation and indentation in the event of a pedestrian collision with the front of the vehicle so as to allow the vehicle's grille area located just in front of this edge 117 to move back, which results in a significant reduction in the risk of injury to the pelvis and / or upper leg areas (femur areas) of this pedestrian.

[0041] With the same objective of facilitating the deformation of at least one lateral portion of this edge in the event of a pedestrian collision with the front of the vehicle, the upper front edge 117 advantageously presents a plurality of deformation zones 118 made of a material more flexible than the rest of this edge 117, for example in an elastomeric material.

[0042] The deformation zones 118, whose width is for example between 10 and 30 mm, are distributed transversely at regular intervals from each other along this edge 117.

[0043] This interval is preferably between 50 and 200 mm.

[0044] As illustrated in Figure 2, these deformation zones 118 preferentially extend over the upper part of the front facade 112 in order to also facilitate the sinking of this upper part of this facade 112 over at least a portion of its width.

[0045] Each deformation zone 118 also has, at its vertical longitudinal median plane, a line of least resistance 118A extending over most of its length and configured to break under a predetermined longitudinal shear stress.

[0046] Extending along parallel vertical longitudinal planes, these necking lines 118A are each constituted by a thinning groove made on the outer face of the upper front edge 117.

[0047] The resistance to shear stress of these necking lines 118A can be adjusted by varying their thickness, which will for example be between 1 and 1.5 mm for a general thickness of the deformation zones 118 between 2 and 2.5 mm.

[0048] The front portion 113B of the peripheral frame 113, the front face 112, the front upper edge 117 with the exception of the deformation zones 118, as well as the rear portion 116A of the guide conduit 116 are preferably formed of a thermoplastic material reinforced possibly with natural and / or synthetic fibers and showing good adhesion with the elastomeric material from which the rear portion 113A of the peripheral frame 113, the front portion 116B of the guide conduit 116 and the deformation zones 118 of the edge 117 are formed; this elastomeric material preferably being made of a thermoplastic elastomer (TPE) such as, for example, a thermoplastic copolyester (TPE-E), a thermoplastic olefin (TPE-O), a thermoplastic polyurethane (TPE-U) or a styrene block copolymer (TPE-S) such as SEBS.

[0049] Preferably, the main body 110 and the guide conduit 116 were produced from a single piece molding using a bi-injection process: the elastomer material elements were overmolded by a second injection onto the other elements previously produced by a first injection.

[0050] According to alternative embodiments not shown, the deformation zones 118 may be devoid of necking lines.

[0051] According to other, unrepresented embodiments, the frangible necking lines can be shaped differently. These can, for example, for example, they can be made up of a series of aligned priming holes distributed at regular intervals.

[0052] According to other unrepresented embodiments, the side walls of the peripheral frame 113 of the air guide 110 have in section an accordion profile or extend diagonally from the inner side towards the front facade 112.

[0053] Such a configuration of these side walls allows to give a certain flexibility to the front portion 113A of the peripheral frame 113 making it possible to avoid, when carrying out a repairable impact, the deterioration of the air guide 110 so as to limit the costs of repairing such a repairable impact and to obtain a better classification of the vehicle with insurance companies.

[0054] Finally, it should be noted that the present invention is not limited to the embodiments described and illustrated, but also encompasses all variants of execution within the grasp of a person skilled in the art, i

Claims

Demands

1. Air guide (110) for a cooling device (100) intended to be fixedly installed in the engine compartment of a motor vehicle between the front bumper and the cooling cassette (10) of that vehicle, said air guide (110) comprising a hollow main body of substantially parallelepiped shape (111) comprising a front face (112) bordered by a peripheral frame (113) extending behind the latter, said front face (112) having at least one passage window (115) formed in its lower part and intended to face a controlled control module of the incoming airflow (120); characterized in that the upper front edge (117) of said main body (111), connecting the front face (112) to the upper wall of the peripheral frame (113), has in section a rounded profile in the form of an arc of a circle.

2. Air guide (110) according to claim 1, characterized in that said rounded profile has a radius greater than or equal to 30 mm.

3. Air guide (110) according to claim 2, characterized in that said radius is between 40 and 60 mm.

4. Air guide (110) according to any one of claims 1 to 3, characterized in that said front upper edge (117) has several deformation zones (118) made of a material more flexible than the rest of this edge and distributed transversely at regular intervals from each other along this edge.

5. Air guide (110) according to claim 4, characterized in that said deformation zones (118) are made of an elastomeric material.

6. Air guide (110) according to any one of claims 4 or 5, characterized in that said deformation zones (118) extend over the upper part of said front face (112).

7. Air guide (110) according to any one of claims 4 to 6, characterized in that each deformation zone (118) has a necking line of least resistance (118A) extending in a vertical longitudinal plane and configured to break under a predetermined longitudinal shear stress.

8. Air guide (110) according to claim 7, characterized in that said necking lines (118A) are each constituted by a thinning groove made on the outer face of said front upper edge (117).

9. Air guide (110) according to any one of claims 1 to 8, characterized in that the side walls of said peripheral frame (113) have in section an accordion profile or extend diagonally from the inner side towards said front face (112).

10. Cooling device (100) intended to be fixedly installed in the engine compartment of a motor vehicle between the front bumper and the cooling cassette (10) of that vehicle, said device comprising an air guide (110) according to any one of claims 1 to 9 and a controlled incoming airflow regulation module (120) with movable flaps (122), mounted in a sealed manner on said air guide (110) opposite said passage window (115).

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