GB2285309A - Adjustable louvred air vent - Google Patents

Abstract

The vent comprises a frame 4 on which louvres 5 are freely hinged, being interconnected by rod 9. The rod is completely protruding with respect to the rear edge 10 of the frame and is pivotably connected to the louvres by way of respective pegs 8 provided with an enlargement portion (11, not shown) which prevents disengagement of the rod from the louvres. The pins 7 of the louvres also comprise an enlargement portion (12, not shown) which prevent disengagement thereof from the frame. The vent may be of a one-piece structure produced by means of over-injection-moulding, and may be for vehicles. <IMAGE>

Description

AIR VENT, IN PARTICULAR FOR MOTOR VEHICLES The present invention concerns an improved air vent which can be used in particular in motor vehicles.

As is known, air vents are usually made of thermoplastic material and mainly comprise a peripheral frame which defines an end of at least one duct for the flow of air to the interior of the vehicle. The frame is disposed fixedly or orientably in the passenger compartment of the vehicle and is associated with at least one series of mutually parallel deflector slats which can be oriented by means of handles or control wheels to control the air flow direction. In particular the slats are hinged to the inside of the frame and are interconnected by means of a rod which is freely rotatably engaged with a respective peg on each slat. Consequently the parallel slats are oriented simultaneously and in an identical fashion about the respective axes with which they are pivotably mounted on the frame, with respect to which the rod performs a translatory movement along a circular arc.

In order to minimise the operations involved in the assembly of the various compartments, it has been proposed that an air vent for motor vehicles may be produced by means of manufacturing procedure of the type described for example in US-A-3263013, making use of an automatic apparatus of the type described for example in EP-B-0147571.

In brief terms, that solution provides for the use of a rotary mould having three stations: - In the first station the slats are injectionmoulded, being disposed beside a rod which is injectionmoulded in the preceding station; - in the second station the rod is coupled to the slats, on respective pegs of which corresponding holes in the rod are axially fitted; and - in the third station the peripheral frame is over-injection-moulded around the slats which are thereby mounted in position. At the same time but separately and in an adjacent position a rod which will be fitted to a subsequent vent is injection-moulded.

The thermoplastic material of the rod and the frame have a different melting point (preferably lower) than that of the slats whereby in the finished vent the frame, the slats and the rod are freely pivotably connected together as described hereinbefore.

That procedure is unsatisfactory for various reasons. The equipment for the injection-moulding procedure is particularly complex and expensive and has a relatively reduced level of productivity.

In addition, in order to compensate for the variations in contraction due to hardening of the frame and the slats and thus to comply with the dimensional tolerances involved in the finished vent the slats must integrally comprise respective flexible projections which are capable of compensating for axial clearances with respect to the frame. Those flexible projections complicate and weaken the structure of the slats which moreover can become undesirably uncoupled from the frame during the movement of the vent, for example during transportation thereof or during fitting thereof to a motor vehicle.

In any case the rod is simply fitted axially to the appropriate pegs of the slats, from which therefore it can easily become disengaged during the movements of the vent. To minimise that shortcoming the rod is positioned in the space between an end of the slats and the adjacent edge of the frame in such a way as to limit the possible displacement thereof. In particular, with any orientation of the slats, the frame is at least partially disposed opposite the rod. That creates geometrical constraints (in terms of the movements of the moulds) during the procedure for moulding and assembly of the components of the vent which has to be produced in the complicated manner described hereinbefore.

The main aim of the present invention is that of providing an air vent, in particular for motor vehicles, of a simple robust structure which does not give rise to problems in regard to separation of the components during movement thereof.

Another aim of the invention is that of providing an air vent of the specified type which can easily be produced automatically and quickly and at low industrial cost.

In accordance with the invention there is provided an air vent, comprising a peripheral frame on which a plurality of substantially parallel deflector slats are freely hinged, the slats being interconnected by means of at least one rod which is freely pivotably connected to the slats, the slats being orientable with a translatory movement of the rod along a virtual circular arc, wherein said rod is positioned in such a way as to be completely protruding in at least part of said virtual circular arc with respect to at least part of the rear edge of the frame, the rod being pivotably connected to at least one of the deflector slats by way of hinge means provided with abutment means for preventing disengagement of the rod from the slats.

The invention will be further described by way of non-limitative example with reference to the accompanying drawings, in which: Figure 1 is a front view of a preferred embodiment of the vent according to the invention.

Figure 2 is a view of the vent in section taken along line II-II in Figure 1; and Figure 3 is a view on an enlarged scale of the vent in section taken along line III-III in Figure 2.

With particular reference to Figures 1 and 2 the vent is made of thermoplastic material and mainly comprises a peripheral support frame 4 which defines the end of at least one duct for the flow of air to the interior of the vehicle. In per se known manner the frame 4 can be mounted in a fixed or movable position in the passenger compartment of a vehicle, for example, and the vent is preferably provided with at least one butterfly flap valve or the like for regulating the rate of flow of the air which passes into the passenger compartment. The butterfly flap valve and the associated actuating members are know per se and are not shown for the sake of simplicity.

The direction of the air flow can be regulated by means of at least one series of substantially mutually parallel orientable deflector slats 5 which are pivotably mounted freely rotatably along a circular arc on opposite sides 6 of the frame 4. As shown in Figure 3 in particular the slats 5 integrally comprise on respective opposite ends pins 7 by means of which they are freely pivotably mounted on the sides 6 of the frame. In addition, at positions corresponding to at least one of said opposite ends the slats 5 integrally comprise respective pegs 8 which are parallel and staggered with respect to the adjacent pins 7.

Preferably the pegs 8 are disposed at positions corresponding to the rear edge of the slats 5, as is clearly apparent from Figure 2.

The deflector slats 5 are interconnected by means of at least one rod 9 which is provided with through holes, into each of which the peg 8 of a respective slat 5 freely rotatably engages. The slats 5 are therefore orientable synchronously about the respective pins 7, for example by way of a conventional control lever system (not shown), in such a way as to vary the direction of the flow of air issuing from the vent. In known manner the deflector slats are oriented by a translatory movement of the rod 9 along a virtual circular arc.

In accordance with an aspect of the invention the rod 9 is positioned in such a way as to be completely protruding with respect to at least part of the rear edge of the frame 4 (to the left in Figure 2), in particular with respect to the rear edge 10 of the adjacent side 6 of the frame, in at least part of the circular arc described by the rod during the above-mentioned translatory movement. That can be achieved by suitable dimensioning of the components or by providing at least one of the sides 6 of the frame 4 with a rear edge 10 which is lowered or reduced with respect to the remaining part of the frame, as shown in Figure 2.

In any case that positioning of the rod 9 eliminates the usual geometrical constrains (referred to hereinbefore) which are encountered during injectionmoulding of a relatively complex component such as an air vent which comprises three different main components (frame 4, slats 5, rod 9) which are interconnected and relatively movable with respect to each other. In particular the vent according to the invention can advantageously be produced by means of an injection-moulding process of the type described in above-mentioned US-A-3263013, using a simple moulding apparatus of the conventional type comprising a movable mould having two stations.

More precisely the air vent according to the invention can preferably be produced in the following manner: - in a first station the frame 4 and the rod 9 are simultaneously injection-moulded in a suitable mould, using thermoplastic material having a relatively high melting point; - in a second station the slats 5 are simultaneously injection-moulded, using thermoplastic material having a lower melting point. The slats 5 are moulded in a mould partially formed by the frame 4 and the rod 9 which were previously moulded in the first station.

As a result, by means of a simple two-phase moulding process, the main components of the vent are shaped and mounted in position, being freely movably coupled to each other.

In accordance with a further aspect of the invention which exploits the absence of substantial geometrical constraints during the moulding procedure, the peg 8 of at least one slat 5 is provided with an enlargement portion 11 integrally produced at the free end thereof. As will be clear from Figure 3, the enlargement portion 11 is capable of bearing against a corresponding axial portion of larger diameter of the associated hole in the rod 9, in which the peg 8 is inserted. The enlargement portion 11 thus constitutes for the rod 9 a travel-limiting means which prevents axial disengagement thereof from the pegs 8 of the deflector slats 5. Preferably each peg 8 of each slat 5 comprises a respective enlargement portion 11.

In accordance with a further aspect of the invention at least one pin 7 of at least one of the deflector slats 5 is produced with an enlargement portion 12 which, similarly to the enlargement portion 11 on the peg 8, is produced integrally at the end thereof. The enlargement portion 12 is preferably positioned in a corresponding seat formed by a recess on the outward side of the frame 4; that seat constitutes an enlarged axial portion of a through hole, into which the pin 7 is fitted. Preferably at least one pin 7 of each slat 5 comprises a respective enlargement portion 12.

In any case the enlargement portion 12 advantageously prevents any axial disengagement of the slats 5 from the frame 4. In addition if substantially all the pins 7 of the slats 5 have a similar enlargement portion 12, that minimises any deformation phenomena in respect of the vent, which are caused by differences in contraction upon hardening of the frame 4 and the slats 5.

As will be apparent to a man skilled in the art from what has been described hereinbefore and illustrated, the enlargement portions 11 of the pegs 8 and the enlargement portions 12 of the pins 7 can be produced in a simple fashion during the phase involving injection-moulding of the slats 5, care being taken to ensure that respective movable mould portions are disposed beside the outside surfaces of the rod 9 and the frame 4. It will be appreciated that this is possible by virtue of the fact that the particular, completely protruding positioning of the rod 9 makes the outside surfaces of both the components 9 and 4 easily accessible.

To sum up the air vent according to the invention is of a substantially "monolithic" structure, that is to say comprising a frame 4, deflector slats 5 and a rod 9 which are relatively moveable with respect to each other, while being non-disengageably interconnected. That provides the vent with a particular degree of robustness and reliability and also eliminates any possibility of accidental detachment of parts during movement of the vent itself.

In addition the vent according to the invention lends itself to being produced by an 'over-injection' moulding procedure which requires the use of a simple conventional moulding apparatus involving low cost and a high level of productivity.

It will be appreciated that the air vent described may be the subject of numerous modifications which are still within the scope of the invention. For example the pivotal connection and abutment means 7,8, and 11,12 and also the respective coupling holes and seats can be produced on the various components in a substantially mirror-image relationship with respect to the structure described above and illustrated soley by way of example.

In addition the air vent according to the invention may be used in apparatuses of different types, such as ventilation convectors or the like.

Claims (6)

1. An air vent, comprising a peripheral frame on which a plurality of substantially parallel deflector slats are freely hinged, the slats being interconnected by means of at least one rod which is freely pivotably connected to the slats, the slats being orientable with a translatory movement of the rod along a virtual circular arc, wherein said rod is positioned in such a way as to be completely protruding in at least part of said virtual circular arc with respect to at least part of the rear edge of the frame, the rod being pivotably connected to at least one of the deflector slats by way of hinge means provided with abutment means for preventing disengagement of the rod from the slats.

2. An air vent according to claim 1 wherein the rod comprises through holes, in each of which a peg of a respective deflector slat is freely rotatably engaged, wherein said abutment means comprise an enlargement portion provided integrally with a peg of at least one deflector slat.

3. An air vent according to claim 1 or 2 wherein the deflector slats are hinged on the peripheral frame by means of pins which are freely, rotatably engaged with corresponding holes in the frame wherein integrally provided on at least one pin of at least one deflector slat is an enlargement portion capable of bearing in a corresponding seat of the frame in such a way as to prevent disengagement of the slats from the frame.

4. An air vent according to claim 3 wherein said seat constitutes an enlarged axial portion of one of said holes in the frame and forms a recess on the outward side of said frame.

5. An air vent constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

6. A motor vehicle having an internal ventilation system having at least one air vent according to any one of the preceding claims for distributing air to the interior of the vehicle.