Automobile heat exchanger module comprising a fan shroud and a heat exchanger, in particular for motor vehicle

A heat exchanger module for a motor vehicle having a fan shroud mounted on a heat exchanger. The shroud includes two blocks that extend from a first side of a duct and are adapted to engage corresponding housings in a first manifold of the heat exchanger. Two spring clips extend from a second side of the fan duct and have an aperture for accommodating a lug projecting from a side face of a second manifold of the heat exchanger.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The invention relates to heat exchangers, particularly for motor vehicles.
 It relates more particularly to a heat-exchange module comprising a fan
 duct fitted to a heat exchanger with two manifolds.
 2. Description of the Related Art
 It is already known to fit a fan duct onto a heat exchanger, such as a
 radiator for cooling a motor-vehicle engine. In such an application, the
 fan duct is equipped with one or more motor-driven fan units in order to
 channel a flow of air suitable for sweeping the body or bank of the heat
 exchanger.
 The fan duct is generally equipped with lugs which are fixed onto the
 manifolds of the heat exchanger by means of screws or the like. These are
 usually self-tapping screws inserted into blocks or bosses specially
 arranged on the manifolds of the heat exchanger
 Such assembly constitutes a lengthy operation and can [sic] compatible with
 the high rates of the assembly or fitting lines of the motor-vehicle
 industry.
 The object of the invention is principally to surmount such a drawback.
 SUMMARY OF THE INVENTION
 To that end the invention proposes a heat-exchange module of the type
 defined in the introduction, in which the fan duct comprises at least two
 blocks which extend from a first side of the duct and which are suitable
 for being engaged in corresponding housings of a first manifold of the
 heat exchanger, as well as at least two spring clips which extend from a
 second side of the fan duct in a direction opposite to the blocks, the
 said clips each being equipped with an aperture suitable for letting
 through a lug projecting from a side face of a second manifold of the heat
 exchanger.
 Hence, in order to fit the fan duct onto the heat exchanger, it is
 sufficient to engage the blocks of the duct into the housings of the first
 manifold and to engage the lugs of the duct into the corresponding
 apertures of the clips. This assembly operation makes it possible to
 produce a module without having to resort to fixing screws, or the like,
 and to tools.
 In one preferred embodiment of the invention, each clip hangs from a
 stirrup which is attached to the second side of the fan duct and which
 leaves an aperture capable of being traversed by a pin integral with one
 end wall of the manifold, in such a way that the fitting of the fan duct
 onto the heat exchanger comprises a final insertion phase in which the
 blocks penetrate into the housings and simultaneously the pins penetrate
 into the apertures of the stirrups.
 According to yet another characteristic of the invention, each stirrup
 comprises a bridge in which the aperture is formed, and to which the clip
 is attached, as well as two branches linking the bridge to the second side
 of the fan duct, in such a way that, during the final phase of the
 insertion, the clip is first of all pushed away laterally under the action
 of the lug then closes back, allowing the lug to penetrate into the
 aperture in the clip.
 Advantageously, each lug comprises a sloping wall, forming a ramp, in order
 to facilitate the pushing-away of the clip.
 In one preferred embodiment of the invention, the fan duct comprises two
 clips, spaced apart, one of which is suitable for providing a positioning
 reference and the other for taking up dispersion between the second
 manifold and the fan duct.
 The housings of the first manifold are preferably each formed by a U-shaped
 stirrup.
 In one preferred embodiment of the invention, the fan duct comprises three
 spaced blocks suitable for being engaged respectively in three housings of
 the first manifold.
 Advantageously, the fan duct as well as its blocks and its clips are
 produced in a single piece by moulding from a plastic.
 Likewise, it is advantageous for the first manifold and its housings to be
 produced in a single piece by moulding from a plastic. Likewise, the
 second manifold and its lugs are advantageously produced in a single piece
 by moulding from a plastic.
 In one preferred embodiment of the invention, the first manifold and the
 second manifold are intended to extend horizontally, respectively at the
 lower part and at the upper part of the heat exchanger.
 In one preferred application of the invention, the heat exchanger
 constitutes a radiator for cooling a motor-vehicle engine.
 In the description which follows, given by way of example, reference is
 made to the attached drawings, in which:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 The module represented in FIGS. 1 and 4 comprises a heat exchanger 10, here
 consisting of a radiator for cooling a motor-vehicle engine, onto which a
 fan duct 12 is fitted.
 The heat exchanger 10 comprises a body or bank 14 formed by vertical tubes
 (not represented) which are linked respectively to a first manifold 16 and
 to a second manifold 18. These two manifolds are generally horizontal in
 direction, and are intended to be placed respectively at the lower part
 and at the upper part of the heat exchanger.
 The latter comprises an inlet pipe 20 and an outlet pipe 22 (FIG. 1)
 serving respectively for taking in and for discharging a liquid running
 through the heat exchanger, in this example a liquid for cooling a
 motor-vehicle engine. Thus, this liquid runs through the heat exchanger in
 a descending vertical direction.
 The manifolds 16 and 18 are produced by moulding from a plastic, for
 example of the polypropylene type.
 The fan duct 12 comprises (FIG. 1) a back plate 24 of generally rectangular
 shape which is designed to extend parallel to and opposite a large face 26
 (FIG. 4) of the body 14 of the exchanger. This back plate leaves a
 circular aperture 28 (FIG. 1) which is intended to house a motor-driven
 fan unit (not represented) comprising an electric motor driving a
 propeller. This motor-driven fan unit is supported by an open structure 30
 attached to a circular cylindrical wall 32 attached to the back plate 24.
 The assembly constituted by the back plate 24, the open structure 30 and
 the cylindrical wall 32 is produced in a single piece by moulding from a
 plastic, in particular of the polypropylene type, so as to constitute the
 fan duct in its entirety.
 This fan duct is intended to be fitted to the heat exchanger, in such a way
 that the motor-driven fan unit can force a flow of air, by blowing or by
 suction, and that this flow is channelled so as to sweep the body 14 of
 the heat exchanger and cool the liquid which runs through this heat
 exchanger.
 In order to carry out this assembling, the invention makes provision for
 the fan duct 12 to comprise, at its lower part, three blocks 34 (only two
 of which are visible in FIG. 1). These blocks extend from a first side 36
 (lower horizontal side) of the duct 12 and are directed vertically
 downwards. These blocks thus extend substantially in the plane defined by
 the back plate 24 of the duct 12. A central block is advantageously
 provided, bracketed by two lateral blocks, these blocks being moulded
 integrally with the fan duct 12.
 These three blocks 34 are suitable for being engaged in respective housings
 38 formed by U-shaped stirrups 40, moulded integrally with the manifold 16
 (FIGS. 1 and 4). Hence the blocks 34 can be inserted simultaneously into
 the housings 38 by a substantially vertical downward movement.
 The fan duct 12 further comprises two clips 42 (FIGS. 1, 2 and 4), only one
 of which is visible in FIG. 1. These two clips are both attached to a
 second side 44 (upper horizontal side) of the duct 12, in such a way as to
 extend on the opposite side to the blocks 34.
 Each of the clips 42 (FIG. 2) hangs from a stirrup 46 which is attached to
 the second side 44 of the fan duct. More particularly, this stirrup 46
 comprises a bridge 48 to which the clip is attached, as well as two
 parallel branches 50 linking the bridge 48 to the side 44 of the fan duct.
 These branches 50 extend in the continuation of the back plate 24 of the
 duct. The bridge 48 constitutes a plate of generally rectangular shape
 which extends in a plane substantially perpendicular to that of the back
 plate 24 and which is provided with an aperture 70.
 The clip 42 is a spring clip which has one end 52 linked to the bridge 48
 and one curved end 54 turned towards the side 44 of the duct, and which
 extends parallel to this side. The clip 42 is capable of being pushed away
 elastically by deflecting within the housing 56 which is delimited between
 the two parallel branches 50.
 This clip 42 includes an internal aperture 58 suitable for letting through
 a lug 60 (FIGS. 1, 3 and 4) projecting from a side face 62 of the manifold
 18. Each lug 60 comprises a sloping wall 64 forming a ramp.
 Close to each lug 60 a pin 66 is provided (FIGS. 1, 3 and 4), which extends
 from an end face 68 of the manifold 18, this end wall being substantially
 perpendicular to the side wall 62 on which the lug 60 hangs.
 The clips 42 and the corresponding stirrups 46 are moulded integrally with
 the fan duct 12. Likewise, the lugs 60 and the pins 66 are moulded
 integrally with the manifold 18.
 In order to fit the fan duct onto the heat exchanger, it is sufficient
 first of all simultaneously to engage the three blocks 34 in the
 corresponding housings 38 of the manifold 16, then to make the duct 12
 pivot so as to bring the side 44 of the duct close up against the upper
 manifold 18. This closing movement is carried out essentially by a
 pivoting or swinging movement. Next, when the pins 66 are opposite the
 apertures 70 of the stirrups 46, it is sufficient to move the duct by a
 translational movement. This allows the blocks 34 to engage fully into the
 housings 38 and the pins 66 to engage fully into the apertures 70. During
 this final insertion phase, the clips 52 are first of all pushed away,
 under the action of the ramps 64 of the lugs 60, then closed back again
 when the lugs 60 engage in the apertures 58 of the clips 42. The clips
 thus provide the locking of the duct and of the exchanger which are held
 immobilised with respect to one another.
 It should be noted that the clips 42 are not necessarily strictly
 identical. Hence, it is advantageous for one of these clips to be suitable
 for providing a positioning reference and for the other to be suitable for
 taking up dispersion between the manifold 18 and the fan duct 12.
 Obviously, the invention is not limited to the embodiment described above
 by way of example and extends to other variants.
 In all instances, the fitting of the duct onto the exchanger is done in a
 secure away without it being necessary to use fixing means, of the screw
 type or the like, and tools.
 Although the invention has been described by particular reference to a heat
 exchanger comprising two horizontal manifolds, it could be applied to
 other types of heat exchangers, in particular with vertical manifolds.