A MOTOR-VEHICLE AIR-CONDITIONING SYSTEM

Abstract: An air-conditioning system for motor vehicles has a first shutter (10) which is associated with a first aperture (17) and a second shutter (14) articulated coaxially to the first and adapted to cooperate with a second aperture (12) associated with the first shutter (10). The separate or simultaneous operation of the two shutters is achieved by means of a rod (26) the ends of which are articulated to the second shutter (14) and to a rotatable operating member (24) respectively, the rod (26) also being connected to the first shutter (10) by means of a toggle device (32a, 32b) which opens it only when the operating member (24) has reached a predetermined angular position.

Description: The present invention relates to an air-conditioning system for motor vehicles, comprising a hollow support structure with apertures for the passage of air, an operating member which is supported for rotation by the structure, and at least one pair of shutters pivoted to the structure and operated by the operating member through respective transmission means. In systems of the above type, each choking or closure shutter has a respective operative member. This makes the production of the system more complicated while at the same time leaving it to the user to achieve the air-flow distribution in the passenger compartment. This optimisation is not easy and often requires repeated manual operation of the operating levers of the system. The object of the present invention is to provide an air-conditioning system of the type specified at the beginning of the description which does not have the above disadvantages and which also ensures the optimum distribution of the air flow without requiring particular attention by the user. According to the invention, this object is achieved by virtue of the fact that the first shutter, which is adapted to close and/or choke a first aperture in the support structure, has a second aperture which is adapted to be closed and/or choked by a second shutter which is pivoted to the first shutter about a common articulation axis, the transmission means comprising a rod which is pivoted to the rotatable operating member and to the second shutter and which is provided with a device for connecting it to the first shutter, the device being adapted to operate when the operating member is in a predetermined angular position, and resilient means being interposed between the first and second shutters to keep the first shutter closed when the connecting device is in its inoperative condition. By virtue of these characteristics, it is possible to adjust the positions of the two shutters according to a predetermined law by means of a single operating rod so as to ensure the optimum air-flow distribution in the various conditions of use (air being sent to the windscreen, outwards, downwards, etc.). The connecting device preferably includes first and second levers which are pivoted to each other like a toggle, and to the rod and to the first shutter respectively, one of the levers having an abutment for preventing the relative pivoting of the levers beyond a predetermined angle. Further characteristics and advantages of the air-conditioning system according to the invention will become clear from the detailed description which follows with reference to the appended drawings, provided by way of non-limiting example, in which: Figure 1 is a partially-sectioned, schematic perspective view of a portion of an air-conditioning system according to the invention, Figures 2-5 are schematic side views of the portion of Figure 1 in four different operative configurations, and Figure 6 is an exploded perspective view of a detail of Figure 1. With reference to the drawings, the hollow structure of a motor-vehicle air-conditioning system indicated S has a substantially rectangular aperture A. A first shutter 10 for closing or choking the air flow through the aperture A is articulated to the structure S about a horizontal axis X-X and has an end edge 10a which is covered with elastomeric material in order to ensure optimal sealing with an edge A₁ of the aperture A. The first shutter 10, which is rectangular in shape, has a rectangular aperture 12 for cooperating with a second shutter 14 which is articulated to the support structure S coaxially with the first shutter 10. The aperture 12 of the latter has a flange 16 on its edge opposite the articulation axis X-X, the flange having a circular cross-section with its centre of rotation situated on the axis X-X. The second shutter 14 has an auxiliary flange 18 on its edge opposite to the articulation axis X-X, the shape of the flange corresponding to that of the flange 16 of the first shutter 10 so that it can slide coaxially on the latter, ensuring sufficient air sealing. A pin spring 20, whose function will become clear from the following description, is interposed between the second shutter 14 and an abutment portion 16a of the flange 16. An operating system, generally indicated 22, is provided for operating the first and second shutters 10 and 14 respectively. The system includes an operating member 24, which is articulated to the structure S about an axis Y-Y substantially parallel to the articulation axis X-X of the shutters, and a connecting rod 26 which is articulated at 28 to the operating member 24. The rod 26 has an end 26a articulated at 30 to the side of the second shutter 14. The rotation of the operation member 24 thus rotates the second shutter 14 directly about the axis X-X. A toggle device 32, comprising a pair of levers 32a and 32b which are articulated to each other at 34, is interposed between the first shutter 10 and an intermediate portion 26b of the rod 26. The first lever 32a is also articulated at 36 to the intermediate portion 26b of the rod 26 whilst the second lever 32b is articulated at 38 to the first shutter 10 beside its rectangular aperture 12. As can clearly be seen in Figure 6, the first lever 32a has an end abutment 40 for cooperating with an edge 32c of the second lever 32b in order to prevent the two levers of the toggle device 32 from pivoting beyond a predetermined angle. For a description of the operation of the air-conditioning system and, in particular, of the closure and/or choking achieved by means of the two shutters 10 and 14, reference is made to four different configurations of the operating system 22 (Figures 2-5), other intermediate configurations obviously being obtainable. Figure 2 shows the configuration in which both of the shutters 10 and 14 are closed over the apertures A and 12. In this configuration, the first shutter 10 is kept closed by means of the force exerted by the spring 20 which, by cooperating with the second shutter 14 which is kept in position by the rod 26, urges the shutter 10 into abutment with the edge A₁ of the aperture A. The clockwise rotation of the operating member 24 (with reference to Figures 2-5) causes the anticlockwise pivoting of the second shutter 14. This pivoting creates through-apertures beside the second shutter 14. In this configuration, the first shutter 10 is still urged against the edge A₁ of the aperture A by the spring 20. The further clockwise rotation of the operating member 24 leads to the configuration shown in Figure 4 in which the second shutter 14 is completely open and the second lever 32b of the toggle device 32 is brought to bear against the abutment 34 of the first lever 32a. Yet further rotation of the operating member 24 causes the first shutter 10 to open since the levers of the toggle 32 enable the motion of the rod 26 to be transmitted to the shutter 10. During its pivoting, the shutter 10 entrains the second shutter 14 until this is brought to bear against an internal wall S₁ of the structure S (Figure 5), corresponding to a maximum air flow through the aperture A. If the sense of rotation of the operating member 24 is reversed, the same configurations described above are obtained. It is possible, by the suitable shaping of the edge of the auxiliary flange 18, to achieve a variable aperture of complex shape in correspondence with the edge of the aperture 12 so as to enable the air flow distribution to be balanced.

Claims: 1. An air-conditioning system for motor vehicles comprising a hollow support structure with apertures for the passage of air, an operating member supported for rotation by the structure, and at least one pair of shutters pivoted to the structure and operated by the operating member through respective transmission means, characterised in that a first shutter (10) of the pair of shutters (10, 14), which is adapted to close and/or choke a first aperture (A) in the support structure (S), has a second aperture (12) which is adapted to be closed and/or choked by a second shutter (14) which is pivoted to the first shutter (10) about a common articulation axis (X-X), the transmission means comprising a rod (26) which is pivoted to the rotatable operating member (24) and to the second shutter (14) and is provided with a device (32) for connecting it to the first shutter (10), which device (32) is adapted to operate when the operating member (24) is in a predetermined angular position, resilient means (20) being interposed between the first and second shutters (10, 14) to keep the first shutter (10) closed when the connecting device (32) is in its inoperative condition. 2. An air-conditioning system according to Claim 1, characterised in that the connecting device comprises first and second levers (32a, 32b) which are pivoted to each other like a toggle and to the rod (26) and to the first shutter (10) respectively, one of the levers having an abutment (40) for preventing the relative pivoting of the levers (32a, 32b) beyond a predetermined angle. 3. An air-conditioning system according to Claim 1, characterised in that the second aperture (12) has a lateral flange (16) arranged in an L-shape with the first shutter (10) and having a first circular section with its centre of rotation coincident with the articulation axis (X-X) of the shutters (13, 14), the flange (16) being arranged, in order to choke the air flow through the second aperture (12), to cooperate with an auxiliary flange (18) which projects laterally in an L-shape from an edge of the second shutter (14) and which has a shape corresponding to that of the flange (16) of the first shutter (10). 4. An air-conditioning system according to Claim 3, characterised in that the auxiliary flange (18) of the second shutter (14) has a shaped edge which is adapted to form an aperture of complex shape with the edge of the second aperture (12) in order to balance the air flows provided by the system. 5. An air-conditioning system according to Claim 3, characterised in that, when the operating member (24) is rotated, the two shutters (10, 14) successively and progressively assume the following configurations: first and second shutters (10, 14) closed so as to prevent the flow of air through the first and second apertures (A, 12), first shutter (10) closed and second shutter (14) partially open by virtue of the cooperation between the auxiliary flange (18) of the second shutter (14) and the flange (16) of the first shutter (10), first shutter (10) closed and second shutter (14) open, and first and second shutters (10, 14) completely open.

Inventors: DEL MONTE, FRANCO
Applicants: BORLETTI CLIMATIZZAZIONE S.R.L.
Application year: 1990
Main classification: B60H1
IPC codes: B60H1