Ventilation device

Abstract

A ventilation device includes a fan propeller (3) and a motor (5) with an external rotor (7b) for driving the propeller (3). The propeller (3) includes a central hub (11) having a frontal wall (17) and an internal first lateral wall (21) defining an accommodating housing for the external rotor (7b). The external rotor (7b) has a front part (9) and a second lateral wall (9″) bearing against the internal first lateral wall (21) of the central hub (11). The ventilation device further includes a device for snap-fitting over the internal first lateral wall (21) to secure the external rotor (7b) to the central hub (11).

Claims

1. A ventilation device comprising a fan propeller (3) and a motor (5) with an external rotor (7b) for driving the propeller (3), the propeller (3) comprising a central hub (11) having a frontal wall (17) and an internal first lateral wall (21) defining an accommodating housing for the external rotor (7b), and the external rotor (7b) having a front part (9) and a second lateral wall (9″) bearing against the internal first lateral wall (21) of the central hub (11), wherein the device further comprises means (27) for snap-fitting over the internal first lateral wall (21) to secure the external rotor (7b) to the central hub (11); wherein the snap-fitting means (27) comprise a ring (29) mounted on the external rotor (7b) and provided with a plurality of elastically deformable clamps (31), each of the clamps (31) comprising, respectively, a first branch (33a) bearing against the second lateral wall (9″) of the external rotor (7b) and a second branch (33b) bearing against the internal first lateral wall (21) of the central hub (11), so as to clamp together the external rotor (7b) and the central hub (11); and wherein the external rotor (7b) comprises a plurality of magnets and each of the clamps (31) is arranged in a corresponding space between two of the plurality of magnets.

2. The device as claimed in claim 1, wherein the central hub (11) comprises a plurality of accommodating housings (35) for the second branches (33b), each second branch having a corresponding one of the plurality of accommodating housings (35).

3. The device as claimed in claim 2, wherein the housings (35) of the central hub (11) respectively comprise at least one snap-fitting hook (37) corresponding to a respective at least one orifice in a corresponding second branch of the plurality of second branches (33b), wherein the at least one hook (37) engages the at least one orifice.

4. The device as claimed in claim 2, wherein the second branches (33b) respectively comprise at least one snap-fitting hook (37), and wherein the housings (35) of the central hub (11) respectively comprise at least one orifice corresponding to a respective at least one snap fitting hook in a corresponding second branch of the plurality of branches, wherein the at least one hook (37) engages the at least one orifice.

5. A ventilation device comprising a fan propeller (3) and a motor (5) with an external rotor (7b) for driving the propeller (3), the propeller (3) comprising a central hub (11) having a frontal wall (17) and an internal first lateral wall (21) defining an accommodating housing for the external rotor (7b), and the external rotor (7b) having a front part (9) and a second lateral wall (9″) bearing against the internal first lateral wall (21) of the central hub (11), wherein the device further comprises means (27) for snap-fitting over the internal first lateral wall (21) to secure the external rotor (7b) to the central hub (11), wherein the snap-fitting means (27) comprise a ring (29) mounted on the external rotor (7b) and provided with a plurality of elastically deformable clamps (31), each of the clamps (31) comprising, respectively, a first branch (33a) bearing against the second lateral wall (9″) of the external rotor (7b) and a second branch (33b) bearing against the internal first lateral wall (21) of the central hub (11), so as to clamp together the external rotor (7b) and the central hub (11), and wherein the central hub (11) comprises a plurality of accommodating housings (35) for the second branches (33b), each second branch having a corresponding one of the plurality of accommodating housings (35).

6. The device as claimed in claim 5, wherein each of the housings (35) of the central hub (11) respectively comprise at least one snap-fitting hook (37) corresponding to a respective at least one orifice in a corresponding second branch of the plurality of second branches (33b), wherein the at least one hook (37) engages the at least one orifice.

7. The device as claimed in claim 5, wherein the second branches (33b) respectively comprise at least one snap-fitting hook (37), and wherein each of the housings (35) of the central hub (11) respectively comprise at least one orifice corresponding to a respective at least one snap fitting hook in a corresponding second branch of the plurality of second branches, wherein the at least one hook (37) engages the at least one orifice.

8. A ventilation device comprising a fan propeller (3) and a motor (5) with an external rotor (7b) for driving the propeller (3), the propeller (3) comprising a central hub (11) having a frontal wall (17) and an internal first lateral wall (21) defining an accommodating housing for the external rotor (7b), and the external rotor (7b) having a front part (9) and a second lateral wall (9″) bearing against the internal first lateral wall (21) of the central hub (11), wherein the device further comprises means (27) for snap-fitting over the internal first lateral wall (21) to secure the external rotor (7b) to the central hub (11), wherein the snap-fitting means (27) comprise a ring (29) mounted on the external rotor (7b) and provided with a plurality of elastically deformable clamps (31), each of the clamps (31) comprising, respectively, a first branch (33a) bearing against the second lateral wall (9″) of the external rotor (7b) and a second branch (33b) bearing against the internal first lateral wall (21) of the central hub (11), so as to clamp together the external rotor (7b) and the central hub (11), and wherein each of the second branches (33b) has a substantially bent-back end (41).

9. A ventilation device comprising a fan propeller (3) and a motor (5) with an external rotor (7b) for driving the propeller (3), the propeller (3) comprising a central hub (11) having a frontal wall (17) and an internal first lateral wall (21) defining an accommodating housing for the external rotor (7b), and the external rotor (7b) having a front part (9) and a second lateral wall (9″) bearing against the internal first lateral wall (21) of the central hub (11), wherein the device further comprises means (27) for snap-fitting over the internal first lateral wall (21) to secure the external rotor (7b) to the central hub (11); additional means for securing the motor (5) and the central hub (11) in rotation; and wherein the central hub (11) has a predefined number of cylindrical bosses, and wherein the front part (9) of the external rotor (7b) has complementary emergent holes into which the cylindrical bosses are inserted.

10. The device as claimed in claim 9, wherein the frontal wall (17) of the central hub (11) comprises radial protuberances (43) that engage with complementary notches (45) provided on the front part (9) of the external rotor (7b), wherein the central hub (11) has a predefined number of cylindrical bosses, and wherein the front part (9) of the external rotor (7b) has complementary emergent holes into which the cylindrical bosses are inserted.

Description

(1) Other features and advantages of the invention will become more clearly apparent on reading the following description, given as an illustrative and nonlimiting example, and the attached drawings in which:

(2) FIG. 1 is a front view of a ventilation device comprising a fan propeller and a driving motor,

(3) FIG. 2 is a perspective view of FIG. 1,

(4) FIG. 3 is a perspective view of the downstream face of the ventilation device in the direction of flow of the flow of air,

(5) FIG. 4a is a front view of the driving motor of the ventilation device of FIGS. 1 to 3,

(6) FIG. 4b is a perspective view of FIG. 4a,

(7) FIG. 5 is a view in cross section along an axis I-I of FIG. 1,

(8) FIG. 6 is a perspective view of the upstream face of the propeller of the ventilation device of FIG. 2 in the direction of flow of the flow of air,

(9) FIG. 7 is a perspective view of the downstream face in the direction of flow of the flow of air of the propeller of FIG. 5,

(10) FIG. 8 is a perspective view of a ring for attaching the rotor of the motor to the hub of the propeller, and

(11) FIG. 9 is an enlarged view of a portion B of FIG. 8 representing a clamp of the ring of FIG. 8 cooperating with a snap-fitting hook of the central hub of the propeller.

(12) In these figures, the elements that are substantially identical bear the same references.

(13) With reference to FIGS. 1 to 3, the invention relates to a ventilation device 1 comprising a fan propeller 3 and a driving motor 5 for the propeller 3.

(14) It is notably a ventilation device 1 for a cooling module of a motor vehicle engine block (not represented). Such a cooling module generally comprises a heat exchanger such as a cooling radiator. The propeller 3 can be arranged either in front of or behind this cooling radiator.

(15) The driving motor 5, more visible in FIGS. 4a and 4b, is an electric motor, which comprises, according to the embodiment described, a stator 7a and an external rotor 7b.

(16) The stator 7a has at least one winding and the rotor 7b comprises one or more magnets. The rotor 7b comprises, for example, a number of magnets distributed over the circumference of the rotor 7b. The magnets are, according to the embodiment described, permanent magnets.

(17) The stator 7a has fixing lugs 8 for fastening to a support (not represented).

(18) The external rotor 7b is received in the central hub 11 of the propeller 3 (see FIGS. 1 to 3). A complementarity of form is therefore provided between the external rotor 7b and the central hub 11 of the propeller 3 for the rotational driving.

(19) Referring once again to FIG. 4b, the external rotor 7b has a front part 9 and a rear part 9′ opposite the front part 9. The terms “front” and “rear” are used with reference to the direction of flow of the flow of air.

(20) The front 9 and rear 9′ parts are linked together by a substantially cylindrical lateral wall 9″.

(21) According to the embodiment described, the lateral wall 9″ of the external rotor 7b has an external face intended to be in contact with the central hub 11 during assembly, and an opposing internal face oriented toward the interior of the rotor 7b.

(22) The front part 9 of the rotor 7b has through openings 10, more visible in FIG. 4a. The agitated flow of air passes through the openings 10 making it possible to cool the motor 5.

(23) These openings 10 are, according to the embodiment represented, of substantially oblong form.

(24) The openings 10 are for example evenly distributed.

(25) The propeller 3 is driven in rotation about an axis of rotation A (see FIG. 5).

(26) The direction of rotation of the propeller 3 is schematically represented by the arrow F in FIGS. 1 to 3.

(27) When the propeller 3 is driven in rotation by the motor 5, the propeller 3 agitates the air which passes through it and creates a flow of air from upstream to downstream by communicating its rotational energy to it.

(28) This propeller 3 is, for example, produced by plastic injection molding. The mold stripping of the propeller 3 can be done in an axial direction.

(29) Referring to FIGS. 6 and 7, the propeller 3 comprises: a central hub 11, a plurality of blades 13 which extend radially from the central hub 11, and a peripheral shell 15 to which the free ends of the blades 13 are connected.

(30) The central hub 11 is hollow and is also called “bowl”.

(31) This central hub 11 is for example produced by molding at the same time as the rest of the propeller 3.

(32) The central hub 11 is driven in rotation by the rotor 7b.

(33) The rotational securing between the central hub 11 and the rotor 7b is for example obtained by complementarity of form between the central hub 11 and the rotor 7b.

(34) This central hub 11 has: an upstream frontal wall 17 having a central opening 19, an internal lateral wall 21, and a peripheral skirt 23.

(35) In the present description, the terms “upstream” and “downstream” refer to the direction of flow of the flow of air produced by the rotation of the propeller 3.

(36) The frontal wall 17 has a substantially annular form. This frontal wall 17 therefore has an internal first diameter D.sub.1 which corresponds to the diameter of the opening 19, and an external second diameter D.sub.2.

(37) The frontal wall 17 is arranged flush with the front part 9 of the external rotor 7b.

(38) The peripheral skirt 23 has a substantially cylindrical form. It extends downstream from the frontal wall 17.

(39) The blades 13 are connected to this peripheral skirt 23.

(40) The frontal wall 17 and the peripheral skirt 23 are for example linked together by a rounded section 25.

(41) Similarly, the internal lateral wall 21 extends downstream from the frontal wall 17. This internal lateral wall 21 is substantially cylindrical and delimits the opening 19 of the frontal wall 17. The internal lateral wall 21 defines an accommodating housing for the driving motor 5 (see FIGS. 2, 3 and 6 and 7), more specifically for the external rotor 7b of the motor 5.

(42) In particular, a complementarity of form is provided between the internal lateral wall 21 of the central hub 11 and the external rotor 7b of the motor 5.

(43) This internal lateral wall 21 has an external face and an internal face opposite the external face. The external face of the internal lateral wall 21 is intended to be in contact with the external face of the lateral wall 9″ of the external rotor 7b on assembly. The internal face of the internal lateral wall is arranged facing the peripheral skirt 23 of the hub 11.

(44) The driving motor 5 is generally mounted coaxial to the central hub 11 of the propeller 3, as illustrated by FIGS. 1 to 3.

(45) Once the motor 5 is assembled with the central hub 11, the frontal wall 17 of the central hub 11 is bearing against the front part 9 of the rotor 7b.

(46) Furthermore, in order to ensure the mechanical secure attachment between the motor 5 and the hub 11, the ventilation device 1 comprises means for fastening the central hub 11 to the rotor 7b.

(47) These fastening means are borne on the one hand by the central hub 11 and on the other hand by the external rotor.

(48) They are, according to the embodiment described, snap-fitting means 27, more visible in FIGS. 5, 8 and 9, which make it possible to attach together the internal lateral wall 21 of the central hub 11 and the lateral wall 9″ of the external rotor 7b.

(49) The snap-fitting means 27 are for example borne by the rotor 7b and suitable for cooperating with the central hub 11.

(50) More specifically, according to the embodiment illustrated in FIGS. 5 and 9, the snap-fitting means 27 are borne by the rotor 7b and cooperate with complementary means borne by the internal cylindrical wall 21 of the central hub 11.

(51) As can be seen better in FIGS. 4a, 4b and 8, the snap-fitting means 27 comprise, according to the embodiment illustrated, a ring 29 mounted on the external rotor 7b; this ring 29 is provided with a plurality of elastically deformable clamps 31.

(52) These clamps 31 are, for example, arranged between the magnets of the rotor 7b. This arrangement allows for the angular immobilization of the clamps 31.

(53) More specifically, the ring 29 is mounted on the rear part 9′ of the rotor 7b.

(54) The clamps 31 can be evenly distributed by a predefined angular pitch, as in the example illustrated in FIG. 8.

(55) Each clamp 31 comprises a first branch 33a and a second branch 33b.

(56) On assembly of the motor 5 and the central hub 11, the first branch 33a of a clamp 31 is arranged bearing against the external rotor 7b, more specifically bearing against the internal face of its lateral wall 9″ (FIGS. 3, 4b and 9).

(57) For its part, the second branch 33b is arranged bearing against the central hub 11.

(58) More specifically, a second branch 33b of a clamp 31 is for example received in a complementary housing 35 of the central hub 11. The hub 11 therefore comprises for this purpose a plurality of complementary housings 35 to receive the second branches 33b of the plurality of clamps 31.

(59) These housings 35 are, according to the example illustrated, defined in the internal lateral wall 21 of the central hub 11.

(60) The clamps 31 thus make it possible to hold together the external rotor 7b and the central hub 11 by clamping.

(61) There is therefore no need to provide a significant quantity of material for the frontal wall 17 of the central hub 11 because the securing is not done at this frontal wall 17 but at the lateral walls 21 and 9″ respectively of the central hub 11 and of the external rotor 7b. This frontal wall 17 can thus have a central opening 19 that is larger than in certain solutions known from the prior art.

(62) Furthermore, the snap-fitting means are, according to the embodiment described, borne on the one hand by the central hub 11 and on the other hand by the clamps 31.

(63) According to the example illustrated in FIG. 9, the housings 35 of the hub 11 respectively comprise at least one snap-fitting hook 37 and complementing this (see FIGS. 8 and 9), the second branches 33b of the clamps 31 respectively comprise at least one orifice 39 in which an associated hook 37 engages.

(64) The cooperation between a snap-fitting hook 37 and an orifice 39 is more visible in FIG. 9 showing a close-up portion B of the cross-sectional view of FIG. 5.

(65) The snap-fitting of the hook 37 in an associated orifice 39 makes it possible to secure the rotor 7b to the central hub 11 and to axially block the central hub 11 of the propeller 1 relative to the rotor 7b.

(66) As an alternative, the snap-fitting hooks 37 can be borne by the second branches 33b of the clamps 31 and the housings 35 can comprise a complementary orifice in which the hook 37 is engaged.

(67) Furthermore, the second branches 33b of the clamps 31 can respectively have a substantially bent-back end 41. This bent-back end 41 facilitates the insertion of the second branch 33b into the corresponding housing 35.

(68) Furthermore, referring to FIGS. 1, 2 and 9, it is possible to provide, on the frontal wall 17 of the central hub 11, one or more radial protuberances 43 oriented toward the external rotor 7b.

(69) Thus, according to the example illustrated in the figures, the central hub 11 has a plurality of protuberances 43. The protuberances 43 extend radially relative to the axis of rotation A of the propeller 3 and are oriented toward the rotor 7b.

(70) A protuberance 43 engages a complementary notch 45 provided on the front part 9 of the rotor 7b. The rotor 7b therefore has, complementing the protuberances 43, a number of associated complementary notches 45. The notches 45 can be seen better in FIGS. 4a and 4b.

(71) The cooperation between the protuberances 43 and the notches 45 completes the rotational securing of the central hub 11 to the rotor 7b.

(72) A reverse construction can be envisaged in which it is the rotor 7b which has one or more protuberances suitable for engaging in an associated notch provided on the frontal wall 17 of the central hub 11.

(73) Any other addition for securing the rotation of the central hub 11 and the motor 5 can be envisaged.

(74) As a variant or as an alternative, the central hub 11 can have a predefined number of cylindrical bosses (not represented) and the front part 9 of the rotor 7b can have complementary emergent holes into which these cylindrical bosses are inserted.

(75) Moreover, the central hub 11 can, furthermore, have internal ribs 47, visible in FIGS. 3 and 7.

(76) These internal ribs 47 extend radially relative to the axis of rotation A of the propeller 3 opposite the blades 13.

(77) These internal ribs 47 make it possible to rigidify the central hub 11.

(78) These internal ribs 47 can also be used to force the ventilation into the central hub 11 so as to cool the driving motor 5 driving the propeller 3.

(79) In practice, when the propeller 3 is driven in rotation, the internal ribs 47 agitate the air present inside the central hub 11. This air is therefore discharged toward the outside of the central hub 11 downstream, and, in addition, the aerodynamic force induced by the internal ribs 47 makes it possible to suck air into the driving motor 5 before discharging it also toward the outside of the central hub 11.

(80) Furthermore, the internal ribs 47 can be evenly spaced at a predefined angular pitch.

(81) Obviously, the internal ribs 47 may not be evenly spaced.

(82) Moreover, the internal ribs 47 are for example produced by plastic injection molding in the same mold as the rest of the propeller 3.

(83) In particular, the internal ribs 47 can be produced in a single piece with the central hub 11 by molding. The mold striping can still be done in an axial direction.

(84) As a variant, the internal ribs 47 can be produced separately from the rest of the propeller 3 and then assembled with the propeller 3. Any means of assembling the internal ribs 47 with the central hub 11 can be envisaged.

(85) With respect to the blades 13, they extend from the peripheral skirt 23 of the central hub 11 to the peripheral shell 15 (see FIGS. 1 to 3 and 6 and 7).

(86) These blades 13 are generally identical.

(87) The blades 13 respectively have a leading edge 49 which comes first into contact with the flow of air upon the rotation of the propeller 3, and a trailing edge 51 opposite the leading edge 49.

(88) For its part, the shell 15 has a cylindrical wall 53, to which the ends of the blades 13 are connected, and which is continued, with a flare 55 (see FIG. 7).

(89) Thus, the propeller 3 is clipped onto the external rotor 7b of the motor 5 via snap-fitting means 27 that are directly assembled on the external rotor 7b.

(90) In practice, the rotor 7b is equipped with one or more clamps 31 secured to the rotor 7b via the ring 29 mounted on the external rotor 7b.

(91) The central hub 11 of the propeller 3 is centered on the external diameter of the rotor 7b and is inserted into the clamps 31, the snap-fitting means on the clamps 31 lock the position of the propeller 3 and also allow for the rotational driving of the central hub 11 and therefore of the propeller 3, by the external rotor 7b of the motor 5.

(92) This assembly makes it possible to have a compact solution.

(93) In practice, the central hub 11 of the propeller 1 is flush with the frame of the motor 5. There is not additional thickness, as for example according to a prior art solution in which the fastening is done for example by screwing onto the frontal wall. This system therefore makes it possible to minimize the number of components and simplifies the assembly operations, in particular by comparison with the screwing-based prior art solution.